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[1] "Eighteenth annual ieee applied power electronics conference and exposition - volume 1," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 601. The proceedings contain 90 paper from the Conference on Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition - Volume 1. Topics discussed include: defining the future for microprocessor power delivery; scalable data center architecture for on-demand power infrastructure; power electronics in hybrid electric vehicle applications; a novel single-stage full-bridge buck-boost inverter and model of permanent magnet inductor type synchronous motor. [2] "Eighteenth annual ieee applied power electronics conference and exposition - volume 2," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 617. The proceedings contains 97 papers from the Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition- Volume 2. The topics discussed include: photovoltaic convertors; independently sourced parallel-connected power systems with maximum power tracking; a reduced common mode hysteresis current regulation strategy for multilevel inverters; a complete solution to the harmonic elimination problem; and high performance, low impedance power interconnects. [3] A. M. Abou-Alfotouh, A. V. Radun, H.-R. Chang, and C. Winterhalter, "A 1 mhz hard-switched silicon carbide dc/dc converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 132. Silicon Carbide (SiC) is a wide bandgap semiconductor material that offers performance improvements over Silicon (Si) for power semiconductors with accompanying benefits for power electronics applications that use these semiconductors. The wide bandgap of SiC results in higher junction forward voltage drops, so SiC is best suited for majority carrier devices such as FETs and Schottky diodes. The wide bandgap of SiC results in it having a high breakdown electric field, which in turn results in lower resistivity and narrower drift regions in power devices. This dramatically lowers the resistance of the drift region and means that SiC devices with substantially less area than their corresponding Si devices can be used. The lower device area reduces the capacitance of the devices enabling higher frequency operation. Here the results from a 1 MHz hard-switched DC/DC converter employing SiC JFETs and Schottky diodes will be presented. This converter was designed to convert 270Vdc to 42Vdc such as may be needed in future electric cars. The results provide the performance obtained at 1 MHz and demonstrate the feasibility of a hard-switched DC/DC converter operating at this frequency. [4] A. Alderman, G. Kennedy, and K. Rinne, "New technical marketing research methods - a process for achieving focused results," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 196. One of the greatest challenges confronting marketing has been the gathering, digesting, and prioritizing technical marketing information. Today, gathering the information is a lot easier via the Internet. In some ways it is much more difficult due to the amount of information available and the accuracy of that information. This was dramatically exemplified in a recent technical study conducted on behalf of an industry association. This paper provides the details of the data gathering and analysis process used to condense it into easily usable material on over 4000 ICs that are available today for dc-dc power supplies. The Issues are identified that confront such an undertaking. The developed survey provides Insight into methods that can effectively identify, sort, and prioritize significant amounts of technical data. The results are reported and examined as to the effectiveness. Finally the surprises encountered and lessons learned are candidly stated with further suggestions for process improvement. Engineering and marketing managers may find this process helpful for future data gathering for any technology. [5] C. Attaianese and G. Tomasso, "Optimal low switching frequency modulation of a front-end inverter feeding induction motors," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 833. In power converters, PWM techniques generally offer acceptable spectral shapes for load currents only if high switching frequencies are adopted. In medium-high power applications, in order to reduce the EMI and commutation losses, the basic goal of the modulation strategies must be the minimization of the harmonic distortion by keeping, at the same time, the switching frequency to a low value. In the paper, this feature is achieved for an ac drives by adopting a front-end inverter structures. In fact, the possibility of achieving variable dc link voltages allows to perform an optimization procedure which drastically reduce the motor current harmonics working with very low value of the switching frequency. The proposed technique has been validated by means of an experiment analysis and a performance comparison with a traditional space vector modulation technique. A full EMC analysis is also performed to evaluate radiated and conducted emissions. [6] M. R. Baiju, K. K. Mohapatra, V. T. Somasekhar, K. Gopakumar, and L. Umanand, "A five-level inverter voltage space phasor generation for an open-end winding induction motor drive," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 826. A topology for voltage space phasor generation equivalent to a 5-level inverter for an open-end winding induction motor is presented in this paper. The open-end winding induction motor is fed from both ends by two 3-level inverters. The three level inverters are realised by cascading two 2-level inverters. This inverter scheme does not experience neutral point fluctuations. Of the two 3-level inverters only one inverter will be switching at any instant in the lower speed ranges. In the multi level carrier based SPWM used for the proposed drive, a progressive discrete DC bias depending upon the speed range is given to the reference wave to reduce the inverter switchings. The drive is implemented and tested with a 1Hp open-end winding induction motor and the experimental results are presented. [7] A. Barrado, R. Vazquez, A. Lazaro, J. Pleite, J. Vazquez, and E. Olias, "New dc/dc converter with low output voltage and fast transient response," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 432. A new alternative to get fast transient response DC/DC switching converters is presented in order to feed devices such as microprocessors and DSPs. The topology of the switching power supply is composed of two buck converters connected in parallel, each one of them with different aims, controlled by means of the Linear-Non-Linear control. In this paper, the LnL control is reviewed and applied to the proposed power supply (fast response double buck, FRDB). Also, experimental results are obtained to show the main features of the proposed converter and to compare them with the features of some other solution. [8] S. Behera, S. P. Das, and S. R. Doradla, "A novel quasi-resonant inverter for high performance induction motor drives," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 819. A novel quasi-resonant inverter is proposed for a high performance induction motor drive. With the exception of auxiliary switch in the resonant link, all other devices in the resonant link and inverter are operated under zero-voltage switching (ZVS). The auxiliary switch is turned on under zero-current switching (ZCS), but turned off hard. The dc link voltage is clamped to source voltage. The quasi-resonant inverter-fed Induction motor is operated under direct torque control (DTC) scheme. The d-q model of the complete scheme is formulated and analyzed by SABER simulator. The simulation is extended with a robust, reduced order stator flux observer. Both the schemes with and without observer have been implemented on a laboratory-sized experimental setup. A comparison of simulation and experimental results under identical operating conditions reveals good agreement. [9] A. R. Beig and V. T. Ranganathan, "Space vector based bus clamped pwm algorithms for three level inverters: Implementation, performance analysis and application considerations," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 569. This paper describes the different types of space vector based bus clamped PWM algorithms for three level inverters. A novel bus clamp PWM algorithm for low modulation indices region is also presented. The principles and switching sequences of all the types of bus clamped algorithms for high switching frequency are presented. Synchronized version of the PWM sequences for high power applications where switching frequency is low is also presented. The implementation details on DSP based digital controller and experimental results are presented. The THD of the output waveforms is studied for the entire operating region and is compared with the conventional space vector PWM technique. The bus clamped techniques can be used to reduce the switching losses or to improve the output voltage quality or both. Different issues dominate depending on the type of application and power rating of the inverters. The results presented in this paper can be used for judicious use of the PWM techniques, which will result in Improved system efficiency and performance. [10] C. Branas, F. J. Azcondo, and S. Bracho, "Design of lc<sub>p</sub>c<sub>s</sub> resonant inverters as a power source for hid lamp ballast applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1214. This paper presents a new criterion for the design of resonant inverters for driving high intensity discharge (HID) lamps. The proposed converter behaves almost as a power source, for a wide load range, regardless of the lamp aging. In order to achieve a better production yield at industrial scale, the analysis of lamp power sensitivity regarding the tolerance of the circuit components is carried out. The design is validated with experimental results and a statistical simulation by the Monte Carlo method. [11] S. Chandrasekaran and V. Mehrotra, "Matrix integrated magnetics (mim) for low voltage, interleaved dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 103. In this paper, we present the application of the Matrix Integrated Magnetics (MIM) core to an interleaved current doubler rectifier (ICDR) controlled according to the symmetric modulation scheme. Detailed modeling and design equations that describe the effect, due to magnetic coupling, of integrating the magnetics of two CDRs on a single core structure on the currents and fluxes are presented. Comparative analyses between an ICDR using a MIM core and two El-cores and a CDR using a single El-core for a 48V-3.3V/100W DC-DC converter design example show that the MIM core can be effectively used for the ICDR providing substantial benefits over a dual EI-18 core solution or a single EI-22 core. Preliminary experimental results from a 100W, 48V-3.3V ICDR laboratory prototype demonstrating the validity of the MIM core structure for this application are presented. [12] L.-K. Chang and H.-F. Liu, "A flexible and low cost design for flyback ac/dc converter with harmonic current correction," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 677. A new simple flyback AC/DC converter with harmonic current correction and fast output voltage regulation is presented. In the proposed AC/DC converter, an extra winding is wounded in transformer and yields two major merits: The bulk inductor used in the conventional boost-based PFC cell is omitted in the proposed converter and consequently almost 1/2 volume and weight in magnetic material can be saved. The voltage across bulk capacitor can be hold under 450v by tuning transformer windings ratio even though the converter operates in wide range of input voltage (90v [similar to] 265v/ac). This new converter compiles with IEC 61000-3-2 under the load range of 200w and it has fast output voltage regulation. [13] S. Chattopadhyay, K. Rajaganesh, and V. Ramanarayanan, "Impedance emulation method for a single phase shunt active filter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 907. A new strategy for harmonic elimination for single phase shunt active filter system is proposed in this paper. The control objective of the filter is defined as: shift the phase angle of the input current with the phase angle of the fundamental load current component. For discreet implementation the objective can be obtained without sensing the input voltage. The controller on the sensed input currents applies phase shifting method and a resistor emulator type input current shaping strategy is applied on the phase shifted current. The proposed control algorithm is computationally simple furthermore effective in filtering the harmonic currents. The simulation results for various kinds of nonlinear loads are presented in this paper. [14] G. Chen, M. Rentzch, F. Wang, D. Boroyevich, S. Ragon, V. Stefanovic, and M. Arpilliere, "Analysis and design optimization of front-end passive components for voltage source inverters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1170. This paper presents a systematic design optimization approach for inductors and capacitors in front-end rectifiers for voltage source Inverters. Analytical relationships between various design variables, operating conditions, and performance and physical constraints are established under nominal, overload and Inrush conditions. A new method to analytically calculate the inrush current is developed considering the nonlinear characteristics of the Inductor core materials. A design optimization program based on the established analytical relationships and a genetic algorithm is developed. Examples show that the optimization process can lead to a smaller/lower-cost inductor and capacitor design. [15] M. Chen, D. Xu, J. Lou, and M. Luo, "Transformer secondary leakage inductance based zvs dual bridge dc/dc converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1082. A novel ZVS dual bridge DC/DC converter is presented. The converter is composed of two dual-transistor-forward converter, coupled with a single high frequency transformer. Zero voltage switching is realized by introducing a proper leakage inductance to the secondary of the high frequency Isolation transformer in cope with a designed PWM control. Operation principle and ZVS condition of the proposed converter are analyzed. Experimental results obtained from a 3.2kW prototype are given. Extensions of the proposed converter topologies are presented. [16] R. Chen, B. Yang, F. Canales, P. Barbosa, J. D. Van Wyk, and F. C. Lee, "Integration of electromagnetic passive components in dps front-end dc/dc converter - a comparative study of different integration steps," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1137. In most of the power electronics converters, the overall footprint and profile of the whole system are in large part determined by the footprint and profile of the passive components and the interconnections between them. Integrated magnetics, Planar magnetics and passive integration techniques have been topics of research for the past few years to reduce the parts count, footprint and profile of the passive components, hence increasing the power density of the whole converter. This becomes especially prominent in the Distributed Power System (DPS) front-end converters, as the trend is moving from 2U (1U=1.75 inches) standard toward 1U standard. This paper presents a comparative study of the integration steps of passive components of an Asymmetrical Half Bridge Circuit (AHBC) for DPS front-end DC/DC converter application. Four AHBC converters using discrete passive components, non-planar integrated magnetic components, planar integrated magnetic components and passive Integrated Power Electronic Module (IPEM), respectively, are constructed and tested. Comparisons are made from the viewpoints of volume, profile, efficiency, EMI and thermal performances of the four converters. The experimental result shows that the passive IPEM, which integrates all the passive components, has much higher power density, lowest profile, lower temperature rise and similar efficiency. [17] S. Chen, T. W. Nehl, J. S. Lai, X. Huang, E. Pepa, R. De Doncker, and I. Voss, "Towards emi prediction of a pm motor drive for automotive applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 14. Technology innovations in automobiles increasingly involve high power electric motor drives, leading to an increasing level of electromagnetic interference (EMI) and the requirements to meet electromagnetic compatibility (EMC). A numerical prediction of EMI/EMC has the potential to evaluate EMI performances at the design stage and before prototyping. It can also help reduce the post-prototype EMC cost by minimizing late re-design and modifications of a drive implementation. This paper describes a systematic approach towards early EMI prediction of motor drives. It is able to calculate the conducted EMI through modeling of parasitic coupling and circuit simulation. Methodologies for extracting parasitic parameters of major EMI components of a PM motor drive are developed using FEM analysis, experimental measurement and analytical approximation. Major EMI characteristics of the PM motor drive is then predicted by using a circuit simulator to solve the motor drive circuitry with high frequency parasitic parameters. Simulation results are compared with experimental data and the effectiveness of the EMI simulation approach is demonstrated. [18] Y. Chen, K. Smedley, F. Vacher, and J. Brouwer, "A new maximum power point tracking controller for photovoltaic power generation," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 58. This paper proposes a new maximum power point tracking (MPPT) method in combination with One-cycle control for photovoltaic power generation. This control scheme is based on the automatic current-adjusting feature of One-cycle control. The output current of the Inverter can be adjusted according to the voltage of the photovoltaic (PV) array so as to extract the maximum power from it. In the mean time, One-cycle control guarantees that the output current is in the same shape of and in phase with the grid voltage. All these are accomplished in one power stage and a simple control circuit. No detection and calculation of power are needed. Compared with previously proposed approaches, this method Is much more efficient and more cost-effective and yet exhibits excellent performance. The principle is explained qualitatively and extensive experiments have been carried out to verify and validate the proposed method. [19] Y. K. Chen, Y. C. Wu, T. F. Wu, and Y. E. Wu, "A single-stage electronic ballast with emergency lighting features," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1185. This paper presents a single-stage electronic ballast with emergency lighting features. The ballast can function as a regular ballast, emergency ballast, battery charger or discharger and power failure detector, achieving regular and emergency lighting features. The single-stage converter used in the ballast is an integration of a bi-directional flyback converter and two half-bridge series-resonant parallel-loaded inverters. Derivation and operating principle of the proposed converter is first presented and an application to regular and emergency lighting is then developed. With the proposed converter and a single-chip microcontroller (EM78P458), a low cost, multi-feature electronic ballast can be readily implemented and installed. Simulation results and hardware measurements have verified its feasibility and the desired features. [20] A. Cheng, "Power electronics: From electronic plumbing to business enabler," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 191. The current state of the power electronics industry is discussed. The companies are focussed on marketing of their products and services. It was concluded that as the power electronics industry grows more sophisticated, the industry needs to work together to educate users and others on its provided values. [21] S. J. Chiang, "A three-phase four-wire power conditioner with load-dependent voltage regulation for energy saving," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 159. This paper presents a multi-functional three-phase four-wire power conditioner. It can compensate the reactive power, harmonic current, unbalanced power and zero-sequence current of the load with a capacity-limitation manner. It also can regulate multiple load voltages simultaneously based on the prescribed P-V characteristics of distinct loads for energy saving. Detailed design of the controllers providing these multiple functions is presented. A 6KVA system with the inverter regulating two different load types simultaneously is implemented. The effectiveness of the proposed techniques is confirmed through some experimental results. [22] J. Chiasson, L. M. Tolbert, K. McKenzie, and Z. Du, "A complete solution to the harmonic elimination problem," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 596. The problem of eliminating harmonica in a switching converter is considered. That is, given a desired fundamental output voltage, the problem is to find the switching times (angles) that produce the fundamental while not generating specifically chosen harmonics. In contrast to the well known work of Patel and Hoft [1][2] and others, here all possible solutions to the problem are found. This is done by first converting the transcendental equations that specify the harmonic elimination problem into an equivalent set of polynomial equations. Then, using the mathematical theory of resultants, all solutions to this equivalent problem can be found. In particular, it is shown that there are new solutions that have not been previously reported in the literature. The complete solutions for both unipolar and bipolar switching patterns to eliminate the 5<sup>th</sup> and 7<sup>th</sup> harmonics are given. Finally, the unipolar case is again considered where the 5<sup>th</sup>, 7<sup>th</sup>, 11<sup>th</sup>, and 13<sup>th</sup> harmonics are eliminated along with corroborative experimental results. [23] H.-J. Chiu, P.-L. Pan, and W.-H. Yeh, "A novel rapid charger of lead-acid batteries with energy recovery," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 756. A novel rapid charger of lead-acid batteries is proposed in this paper. While providing the high charging efficiency and prolonging the lifetime of batteries, the circuit topology exhibits extreme simplicity. Experimental results are shown to verify the feasibility of the proposed rapid charger. [24] S.-W. Choi, C.-Y. Won, and G.-S. Kim, "A new three-phase harmonic-free rectification scheme based on zero-sequence current injection," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 165. This paper proposes a new three-phase harmonic-free rectification scheme based on a zero-sequence injection technique. The proposed scheme incorporates two half-bridge inverters and two single-phase transformers to actively and Individually shape the positive and negative dc rail currents of the rectifier. The shaped zero-sequence harmonic currents are then circulated through the ac side of the rectifier via a zigzag transformer, resulting in pure sinusoidal input currents in the three-phase diode rectifier. A design example along with component ratings calculation is detailed. Experimental results on a 1.5kVA prototype are provided to validate the proposed technique. [25] M. Cichowlas, M. Malinowski, M. P. Kazmierkowski, and F. Blaabjerg, "Direct power control for three-phase pwm rectifier with active filtering function," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 913. A novel Virtual Flux based Direct Power Control Space Vector Modulated (DPC-SVM) for 3-phase PWM rectifier with compensation of higher harmonics function is presented. The active and reactive power is used as a control variables for the PWM rectifier and active filtering operation. As a result several coordinate transformations are eliminated. Simulated and experimental steady state and dynamic performance for PWM rectifier and active filtering operation are presented. Among the main advantages of DPC-SVM are: simple algorithm, good dynamic and operation at constant switching frequency. Additionally a line voltage sensors were replaced by the virtual flux estimator which also help to achieve sinusoidal line current in case of distorted line voltage. [26] R. Cormier, "Providing real customer satisfaction product support from a customer's point of view," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 215. The issues related to real customer satisfaction are discussed. The power product manufacturers provides engineering support with customer service engineers (CSE) and application engineers (AE) to their customers. It was found that it is necessary to understand the challenges that customers encounter in all phases of power supply introduction. [27] K. De Gusseme, D. M. Van de Sype, A. P. Van den Bossche, and J. A. Melkebeek, "Sample correction for digitally controlled boost pfc converters operating in both ccm and dcm," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 389. PFC converters for the higher power range are commonly designed for continuous conduction mode. Nevertheless, at light load, DCM will appear close to the crossover of the line voltage, causing the converter to switch between CCM and DCM. As a result of this switching during a line period, the converter dynamics change abrubtly, yielding input current distortion. Moreover, if digital control is applied, another source of input current distortion is posed by the sampling algorithm. After all, the sampling algorithm is only designed to produce samples of the averaged input current in CCM. In this paper, after a study of the input current distortion caused by the sampling algorithm, a correction factor is derived to compensate for the error on the input current samples. The theoretical results are verified experimentally by using a digitally controlled boost PFC converter. [28] D. I. M. De Silva, N. K. Shrestha, R. Azar, G. A. J. Amaratunga, F. Udrea, P. R. Palmer, D. Chamund, L. Coulbeck, and P. Waind, "Trench gate igbts for zero current switching applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 933. This paper reports on the behaviour of Trench IGBTs in comparison with equivalent DMOS IGBTs in zero current switching converters. Extensive experimental results backed up by accurate Spice modelling are presented. These results indicate the superior performance of Trench IGBTs particularly at high switching frequencies, currents and junction temperatures in resonant applications. [29] A. Dell'Aquila, M. Liserre, V. G. Monopoli, and C. Cecati, "A multilevel front-end stage for traction systems with a passivity-based controller," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 690. This work addresses the control of a high voltage, high power single phase rectifier suitable for traction applications. A multilevel H-bridge single phase configuration has been considered. Such a converter often presents instability problems making difficult its design and uncertain its behaviour. This paper proposes a new controller based on the passivity-based approach. Such a controller allows stability, unity-power factor, good balancing of the two dc links and a satisfactory transient behaviour even in presence of sudden load changes. A different choice of the damping parameters allows fulfilling the system requirements in terms of reduced dc link voltage error or low grid current distortion or to find an optimum trade-off between them. The better performance in comparison with a PI are demonstrated. [30] S. Deng, H. Mao, J. Mazumdar, I. Batarseh, and K. K. Islam, "A new control scheme for high-frequency link inverter design," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 512. A high-frequency link Inverter design with bi-directional power flow using cycloconverter techniques is proposed in this paper. A new control scheme is used to reduce the switching losses and overall size. Detailed operation modes are discussed and the harmonic components for the key waveforms are analyzed with theoretical calculation. The control scheme is verified by both the simulation and experimental results. [31] U. Drofenik and J. W. Kolar, "Teaching thermal design of power electronic systems with web-based interactive educational software," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1029. For designing reliable power electronic systems it is essential to understand basic thermal issues like the stationary and transient relation of the power semiconductor losses the junction temperature and the application of thermal equivalent circuits. Also, thermal properties are of special importance in connection with further increasing the compactness of power converter systems. The aim of this paper is to give an introduction into the basic theory of heat energy conduction and thermal design which should serve as an addition to the Java applets compiled in a the iPES-Thermal, a module of the interactive educational software iPES which is freely available at www.ipes.eth2.ch and employed at the ETH Zurich for supporting an introductory course on power electronics. [32] N. J. Elias, "Instruction set modeling of micro-controllers for power converter simulation," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 996. Simulation has become an increasingly important design tool as power converter technology has evolved. Programmable digital control requires a simulation model that can incorporate the control software without degrading the speed of the simulator. This can be accomplished by extending the instruction set model (ISM) concept originally developed for digital simulations. This paper develops the principles by which the ISM concept can be adapted to the analog/mixed-signal simulation of power converters. A model of a commercial microcontroller is used to present typical simulation applications that demonstrate the important benefits achieved. [33] W. Fei, Z. Lu, L. Xia, D. Jiang, and Z. Wu, "High insulation multiple output switch power supply used for driving of igbts in medium-high voltage inverter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1066. High insulation multiple output switch power supply used for driving of IGBTs in medium-high voltage inverter is developed by means of a high frequency ac current source and special transformers with single-turn primary winding. The number and locations of outputs of the power supply can be arranged very easily to meet the requirements of the inverter. The isolation voltage among all outputs and input can be considerable high if the primary winding is made by high-voltage cable. Compared with other power supply used in same purpose, the proposal one has the advantage in size, weight, cost, efficiency and reliability. With the increase of voltage level and number of devices in the inverter, the proposed power supply will be more advantageous. [34] G. Feng, W. Zhang, and Y.-F. Liu, "An adaptive current mode fuzzy logic controller for dc-to-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 983. This paper introduces a new fuzzy logic controller (FLC) using inductor current feedback for significantly Improving the dynamic performance of DC-to-DC converters. Inductor current plays an important role in high performance DC-to-DC converter control and FLC is suitable to deal with time-varying nonlinear nature of power converters. Based on the feedback of the inductor current, the new control method combines the merits of both the conventional FLC and current mode control. The dynamic performance of power converter system is improved. Furthermore, in order to enhance system robustness and adaptability, a new nonlinear configuration called extended state observer (ESO) Is developed. By using ESO, the influence of load disturbances and parameter changes are precisely estimated and compensated without accurate knowledge of converter parameters. Simulation results have demonstrated that the proposed methods ensure good robustness and adaptability under modeling uncertainty and external disturbance, such as load current variation, supply voltage changes and converter parameter changes. It is concluded that the proposed topology produces substantial improvement of dynamic performances such as small overshoot, more damping and fast transient time under different operating conditions. In addition, small signal frequency response analysis demonstrates that by using the proposed FLC, the bandwidth and phase margin of the closed loop system have been significantly increased. [35] Q. Feng, J. Y. Hung, and R. M. Nelms, "Digital control of a boost converter using posicast," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 990. Analysis, design, simulation and DSP-based implementation of a digital controller using a Posicast element are presented for the boost converter. Different from the classical Posicast approach, the proposed control method here reduces undesirable sensitivity greatly by using Posicast within a feedback loop. Furthermore, unfavorable effects on system stability caused by the RHP zero and parasitic elements in the boost converter's dynamics can be ignored in the design of controller because of its narrow open-loop bandwidth. Transient and frequency responses are presented. The performance of a Posicast-based controller for a boost converter has been investigated through simulation and verified by experiment. The sensitivity of the system dynamical response to variations in controller parameters was examined. The effect of load resistance variation was also tested. [36] A. Fernandez, J. Sebastian, M. M. Hernando, P. Villegas, and J. Garcia, "New self-driven synchronous rectification system for converters with a symmetrically driven transformer," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 352. Synchronous Rectification (SR) is mandatory to achieve good efficiencies with low output voltages. If the transformer is driven asymmetrically without dead times, Self-Driven Synchronous Rectification (SDSR) is a very interesting solution. However, if the transformer is driven symmetrically, the synchronous rectifiers are off during the dead times and, as a consequence, the efficiency is lowered. This paper deals with a new SDSR system that keeps the rectifiers on even during the dead times. Thus, it can be used to obtain very low output voltages, such as 1.5 V, with quite good efficiency. Moreover, it can be used over a wide input voltage range. The new system is implemented in a prototype in order to measure the real efficiency that can be achieved with the proposed scheme. [37] J. Flannery, "Surface mount power converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 812. Application boards on which on-board power supplies are used are populated substantially with surface mount components. These are typically assembled with conventional single or double sided SMT (surface mount technology) reflow processes. The few remaining PTH (plated through hole) components need to be manually placed and soldered either by hand or by a process such as selective wave, selective jet or robotic soldering. The complexity of many modern application boards in terms of layer count and component density, combined with the desire to eliminate these additional process steps is leading to a desire for the elimination of the remaining PTH components of which the dc-dc converter is the most conspicuous. This paper deals with many of the challenges faced when designing and using a state of the art, surface mountable, high density power-supply which must be treated as a single surface mount component. These Issues Include Interconnect design, joint strength and reliability, electrical and thermal conductivity, as well as manufacturing considerations such as pick and place compatibility, inspection and rework. [38] R. Francis and M. Soldano, "A new smps non punch thru igbt replace mosfet in smps high frequency applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 953. The continuous request from the market for higher power density and lower cost in commercial power supplies has forced semiconductor manufacturer to push device optimization to the limit or to develop new device solutions. Some of the new devices can surely Improve performances, but in some cases the price to pay for Increased complexity is too high. The IGBT device has a long history of success in motor drive and inverter applications, where switching frequencies are relatively low compared to SMPS. For this reason the development of new devices has always been driven by different requirements than SMPS ones. An NPT IGBT family has been developed and optimized targeting specifically SMPS applications. This paper shows the feature of this device in a critical comparison with equivalent products available on the marked today. [39] L. Gao, R. A. Dougal, and S. Liu, "Active power sharing in hybrid battery/capacitor power sources," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 497. The objective of this work in to determine to what extent the performance of a battery/capacitor hybrid power source can be improved by isolating the battery through a power converter. The performance of an active hybrid power source (battery/capacitor/converter) is compared to that of a passive hybrid (battery/capacitor) using both simulation and experiment. Particularly in this paper, two cells of Sony US18650 lithium-ion battery and two cells of Maxwell PC 100 supercapacitor are used as the energy storage components in the power source construction. Both the experimental data and the simulation results show that the active hybrid power source achieved greater mass and volume densities of power without drawing excessive currents from the battery. The active hybrid yielded a peak power of 130 W with terminal voltage variation (1.31V), compared to a maximum of 42 W for the passive hybrid with voltage variation 1.7V. [40] W. Gao, E. Solodovnik, R. Dougal, G. Cokkinides, and A. P. Sakis Meliopoulos, "Elimination of numerical oscillations in power system dynamic simulation," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 790. This paper addresses numerical oscillations encountered in power system dynamic simulation resulting from trapezoidal numerical integration rule. Two methods are presented to eliminate the numerical oscillations: trapezoidal with numerical stabilizer method and Gear's second order method. A detailed comparison is given regarding the accuracy of the trapezoidal rule, trapezoidal with numerical stabilizer method, and Gear's method. The validity of the new methods is demonstrated in the simulation of a power electronic circuit within Virtual Test Bed. The new methods are of great significance in performing a meaningful simulation for power electronics circuits. [41] C. Gezgin, "A transient prediction and stability analysis tool for dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1014. An Excel-based tool that calculates both the output voltage deviation V<sub>max</sub> due to load transients as well as small-signal stability characteristics of a DC-DC converter is presented. Using a macromodel of theconverter, the tool calculates and plots the voltage loop gain characteristics of a DC-DC converter for a wide variety of load networks and voltage-sense methods. The tool also predicts stability margins of the converter+load combination and estimates the under/overshoot of the regulated output voltage due to a given load transient. The method used is unique in the sense that 1) it decouples the closed loop system into converter-only and load-only subsytems which allows a very convenient way of calculating loop response when the load is varied; and 2) the converter-only subsystem can be characterized by measured data which yields a very accurate prediction of the loop response, and hence the stability margin. The transient response of the converter is estimated by mapping the closed-loop system to a second order parallel RLC network and analytically deriving the response of the RLC network. The purpose of the tool is to enable the converter user to get an accurate estimate of stability margins and transient response of the module in an application without actually making measurements. [42] R. Giri, R. Ayyanar, and N. Mohan, "Common duty ratio control of input series connected modular dc-dc converters with active input voltage and load current sharing," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 322. A control scheme was proposed to ensure active voltage sharing and load current sharing of 'n' identical dc-dc convertors, connected in series at the input and parallel at the output. Input voltage sharing and output current sharing were achieved by applying a common duty ratio signal to input series, output parallel-connected convertors. A model of the scheme that predicted the dynamic voltage sharing among the convertors was developed. Simulation and experimental results validated the proposed control concept. [43] D. Hammell, M. Holveck, and E. Limpaecher, "Low-cost, scr-based premium power quality variable speed drive technology," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 853. A unique variable speed drive topology is presented. This topology has been shown to use Silicon Controlled Rectifier switches without commutation circuitry at a frequency of 2 kHz to produce input and output waveforms with current total harmonic distortion below 3%. Furthermore, the voltage rise on the output is 1.2 v/us without inductive filtering, which preserves motor insulation and bearing life. The topology is low cost due to its minimal switching complexity. [44] L. Hao and H. A. Toliyat, "Bldc motor full-speed operation using hybrid sliding mode observer," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 286. This paper presents a full speed range control scheme for surface mount BLDC motor. The developed topology looks like field-oriented controls for sinusoidal PM motors but the fifth and seventh harmonics variables have been taken into consideration as well as the fundamental variables. The proposed method results in an increase in developed torque. Also, it shows the same controllability as in the sinusoidal PM motor over the flux weakening operation compared to the conventional six-step BLDC drive system. In this paper, the line-to-line average model of the BLDC motor in rotor multiple reference frame (MRF) first is developed. A sliding mode observer then is introduced to estimate the rotor position and speed used in the MRF. After that, a full speed range control algorithm is developed based on the line-to-line average model. Finally, simulation and experiments have been done to verify the validity of the proposed method. [45] J. G. Hayes, N. O'Donovan, M. G. Egan, and T. O'Donnell, "Inductance characterization of high-leakage transformers," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1150. In this paper, the inductances of high-leakage transformers are Investigated by analysis, measurement, and finite-element simulation. Series-coupling tests, featuring differential coupling (series opposing) and cumulative coupling (series aiding), are conducted in addition to the standard open-circuit and short-circuit tests. This paper initially reviews and discusses the various test approaches featuring the open-circuit, short-circuit and series-coupling tests. Two very different types of high-leakage transformers are then characterized based on these tests. The short-circuit and series-coupling tests performed comparably for Investigating the spatial variations of the primary and secondary leakage Inductances of the high-power, highleakage transformer first investigated. For the second low-power, high-leakage, high-resistance planar transformer the differential-coupling test proves to be a more useful, accurate, and insightful test than the short-circuit test. [46] L. Heinemann, J. Mast, and G. Scheible, "Power supply with high insulation capability to feed electronics on the high potential side in power distribution networks," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 767. Intelligent measurement systems, communication or control equipment on the high potential side of power distribution networks require power supplies with very high insulation capability and low power level. To end up with a low volume, low costs and a high efficiency of the complete system, a resonant switch mode power supply with a special transformer design was selected, designed and built up. The power supply is designed to transfer 2.5 W, guarantees a partial discharge free insulation voltage of more than 50 kV and an insulation test voltages of more than 80 kV. The power supply is based on a class-E converter to utilize the dominating parasitic elements of the high frequency transformer as resonant elements. [47] M. Hirokawa, H. Miyazaki, K. Matsuura, and T. Ninomiya, "Improvement of transient response in high-current output dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 705. The technique of improvement of transient response in high-current output dc-dc converters was investigated. The output voltage deviation of 50mV at a slew rate of 300A/μs was performed on a prototype with an output of 1.3V/130A. It was found that a novel transient detector and synchronous operation of the current doubler rectifiers can be used to improve the transient response of a high-power output VRM. [48] L. Hua and S. Luo, "Design comparisons between primary-side control and secondary-side control using peak current mode controlled active clamp forward topology," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 886. The purpose of this paper is to provide a general comparison between primary-side control and secondary-side control from the perspectives of industrial designs. Definitions and comparisons between the two controls are given, and a small-signal model of active clamp forward topology is developed. Finally, experimental results are presented, with which theoretical analysis and predication are verified. [49] W. Huang, D. Clavette, G. Schuellein, M. Crowther, and J. Wallace, "System accuracy analysis of the multiphase voltage regulator module," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 731. The paper analyzes the system accuracy of the multiphase voltage regulator module (VRM), and identifies the influential factors contributing to the system errors. PSpice Monte Carlo analysis, a more realistic statistical method of system accuracy prediction, is used to simulate the load line of the multiphase voltage regulator module for the next generation microprocessors. The Monte Carlo simulation result is compared with a worst-case analysis, a root-sum-square method, and is verified by the experimental results of a three phase synchronous buck converter. [50] W. Huang, G. Schuellein, and D. Clavette, "A scalable multiphase buck converter with average current share bus," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 438. The paper presents a scalable multiphase synchronous buck converter which meets the tight requirements of the next generation microprocessors. Flexibility in the number of phases (1-16 phases) accommodates requirements of various applications. The converter can be easily expanded or paralleled with other Voltage Regulator Modules (VRM) through an average current share bus. The distributed control IC architecture allows for local phase current signal processing, which minimizes induced noise and facilitates layout while reducing the gate driver to power stage impedance. The experimental results are given to show the advantages of the converter. [51] X. Huang, T. Nergaard, J.-S. Lai, X. Xu, and L. Zhu, "A dsp based controller for high-power interleaved boost converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 327. High power boost converter has become the essential part of the distributed power system that enables energy to be fully utilized in fuel cell powered electric vehicles and stationary power systems. This paper presents a DSP-based fully digital control implementation for an interleaved high power dc/dc boost converter. A dual-loop average current mode current control method is employed to achieve the fast transient response. Different anti wind-up schemes for a typical PI-controller are evaluated through simulation and experiment. Simulation and experiment results of the 20-kW boost converter under start-up condition and load transient condition are also presented. The results show that this typical controller with proper anti wind-up scheme achieves better transient performance than without anti wind-up scheme. [52] B. T. Irving, Y. Panov, and M. M. Jovanovic, "Small-signal model of variable-frequency flyback converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 977. An accurate, straight-forward, small-signal model of the variable-frequency flyback converter is presented. The model, which replaces the switching devices with dependent sources representing average terminal currents, is similar to the discontinuous-conduction-mode, three-terminal switch model presented in the past. However, since the converter always operates at the boundary of discontinuous and continuous-conduction-modes under both steady state and transient conditions, the inductor can be removed from the average large-signal model. In fact, the control-to-output transfer function can be accurately described with its current loop closed at frequencies less than half of the switching frequency. The model is extended to the ringing-choke converter, which is a common type of variable-frequency flyback converter used in many cost-sensitive applications. The small signal model is validated with measurements made on an offline, S-V/ 2-A experimental prototype. [53] Y. Jang and M. M. Jovanovic, "A new three-level soft-switched converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1059. A three-level, constant-frequency, Isolated converter which employs a coupled Inductor to achieve zero-voltage switching (ZVS) of the primary switches in the entire line and load range is described. Because the coupled inductor does not appear as a series inductance in the load current path, it does not cause a loss of duty cycle or severe voltage ringing across the output rectifiers. The operation and performance of the proposed converter was verified on a 1-kW prototype. [54] Y. Jang and M. M. Jovanovic, "A new family of full-bridge zvs converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 622. A family of soft-switched, full-bridge (FB) pulse-width-modulated (PWM) converters that features zero-voltage-switching (ZVS) of all bridge switches over a wide range of input voltage and output load with minimal duty cycle loss and circulating current is described. The ZVS of the primary switches is achieved by employing two magnetic components whose volt-second products change in the opposite directions with a change of phase shift between the two bridge legs. One magnetic component is a transformer while the other magnetic component is either a coupled inductor or a single-winding inductor. The transformer is used to provide isolated output(s), whereas the inductor is used to store energy for ZVS. [55] R. A. Jensen and C. R. Sullivan, "Optimal core dimensional ratios for minimizing winding loss in high-frequency gapped-inductor windings," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1164. Numerical techniques are used to find the inductor core dimensional ratios that minimize winding loss. It is shown that common core shapes result in significant excess losses, even if the shape of the wire winding is optimized. A design example demonstrates the practical implications of this technique for choosing cores-a standard core with dimensional ratios close to optimum provides a 32% savings in power loss compared to another popular core shape. Further improvements in power loss could be achieved by using optimized core shapes. Improvements to software for shape-optimization of windings are described, including accounting for different turn lengths at different radii, the ability to select gaps in different core legs, and better approximations of three-dimensional field geometry. [56] S.-J. Jeong and S.-H. Song, "Current control of 12-pulse regenerative converter for 20ka magnetic power supply," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 256. High current magnetic power supply for superconductivity coil of tokamak requires fast dynamic performance of di/dt and smooth change over of current direction. To meet the specification high performance DSP-based controller is designed for 12-pulse thyristor dual converter with interphase transformer(IPT). Not only the total current of Y and Δ converter units but also the difference for those should be regulated fast and accurately. Proportional and integral controller is designed for difference current control and the controller output is compensated to Δ converter. A new algorithm for the calculation of the Initial firing angle is proposed for the minimization of non-ideal effect during the change over of dual converter currents. [57] Z. Jiang and R. A. Dougal, "Control design and testing of a novel fuel-cell-powered battery-charging station," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1127. This paper presents a novel system design for a fuel-cell-powered battery-charging station. This battery charging station allows multiple batteries to be charged simultaneously. Three baseline static charging algorithms are proposed to coordinate the power distribution among the battery branches. The control strategies include equal rate charging, proportional rate charging and pulse current charging. These charging algorithms are then realized in MATLAB/Simulink, and the current and voltage regulations are Implemented using the classical proportional-integral approach. The system simulation is conducted in VTB by embedding Simulink objects and cosimulating with MATLAB. The experimental tests are performed by compiling Simulink codes and downloading onto the DSpace platform. The simulation and experimental results are also given. [58] T. Jin and K. M. Smedley, "Operation of unified constant-frequency integration controlled three-phase active power filter with unbalanced load," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 148. The theory and experiments have demonstrated that the Unified Constant-frequency Integration (UCI) controller features excellent performance, simple circuitry, and low cost for the control of three-phase APF connected to either symmetrical or asymmetrical three-phase power systems. In reality, three-phase grid voltages and/or three-phase nonlinear loads may not be balanced all the time, therefore it is vital for an APF to be able to handle unbalanced source or load. Studies have shown that the UCI controlled APF performs satisfactorily in unbalanced systems. In continuation, the performance of a three-phase APF working in unbalanced load with a UCI controller is evaluated in this paper. Simulation and experiment results indicate that with UCI control, sinusoid input current can be realized, whether the loads are balanced or unbalanced. [59] I. D. Jitaru, "Self-driven constant voltage reset circuit," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 893. This paper presents a reset mechanism, which combines the advantages of the active clamp reset and the traditional third wire reset technique. In this concept the reset voltage is constant similar to the third wire reset, wherein a constant voltage is applied to the transformer during the reset cycle. The technology has several key advantages from the active clamp reset mechanism. The energy contained in the leakage and magnetizing inductance is recycled, and the voltage across the main switch is clamped. In addition to this, the flux trough the transformer is symmetrical to zero and the duty cycle can be higher than 50%, similar to the active clamp circuit. Though this circuit contains most of the active clamp circuit' key features it does not exhibit its limitations. One of the drawbacks of the active clamp circuit is its behavior during transients wherein the duty cycle changes. During transients, until the reset capacitor charges to its optimum level, the voltage across the switch may reach uncontrollable levels. In this reset technique the voltage across the switch is constant regardless of the duty cycle and reacts to transients without any limitations. In additional to this the implementation is very simple; it does not require any additional driving and timing circuits for the reset switch. The reset switch is driven directly form the transformer by a driving winding and the reset voltage can be easily adjusted by a resistor divider. Using this technology a DC-DC Converter was implemented, providing 1.2 V @ 20 A, from an Input voltage range of 36 V to 60 reaching an efficiency of 86% at full load. [60] X. Kang, E. Santi, J. L. Hudgins, P. R. Palmer, and J. F. Donlon, "Parameter extraction for a physics-based circuit simulator igbt model," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 946. A practical parameter extraction method is presented for the Fourier-based-solution physics-based IGBT model. In the extraction procedure, only one simple clamped inductive load test is needed for the extraction of the eleven and thirteen parameters required for the NPT and PT IGBT models, respectively. Validation with experimental results from various structure IGBTs demonstrates the accuracy of the proposed IGBT model and the robustness of the parameter extraction method. [61] S. Kim and P. N. Enjeti, "Control of multiple single phase pfc modules with a single low-cost dsp," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 375. In this paper, a new control scheme is proposed for controlling multiple single-phase power factor correction (PFC) modules with a single low-cost digital signal processor (DSP). The proposed scheme allows for multiple PFC modules of different current ratings to be operated in parallel and controlled via a single DSP. DSP based control handles simple current sharing and provides size reduction. The paper describes a current sense technique for each PFC module and a closed loop control algorithm for output voltage and Input current control for operating multiple modules. In the example design, switching frequency is set at 120 kHz and two continuous conduction mode (CCM) PFC stages are operated in parallel and controlled via a single TMS320LF2407 DSP. Experimental results show that the proposed scheme is capable to be used for modern switching power supplies. [62] S. Kim, M. H. Todorovic, and P. N. Enjeti, "Three phase active harmonic rectifier (ahr) to improve utility input current thd in telecommunication power distribution system," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 805. Modern telecommunication power supply systems have several parallel connected switch mode rectifiers to provide -48V DC. Typical switch mode rectifier configuration includes a three phase diode rectifier followed by a DC-DC converter. Such a system draws significant harmonic currents for the utility resulting in poor input power factor and high total harmonic distortion (THD). In this paper, a three phase active harmonic rectifier (AHR) scheme is proposed. In AHR scheme, a diode rectifier module is replaced by 6-IGBT PWM rectifier to supply load harmonics as well as its own active power. Each DC-DC converter module is connected to a shared 48V dc-link. The AHR module together with parallel connected switch mode rectifiers is controlled to achieve dean input power characteristics. The VA ratings of AHR scheme is compared with an active power filter (APF) approach. The control design is based on the synchronous reference frame approach. Analysis, simulation and experimental results show that AHR offers several advantages such as lower VA rating, better current control response, efficient use of AHR dc-link, small size, and stable de-link voltage control. [63] T.-H. Kim, B.-K. Lee, and M. Ehsani, "Sensorless control of the bldc motors from near zero to high speed," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 306. This paper presents the theory and practice required to implement a novel sensorless operation technique for the brushless DC (BLDC) motor. The proposed new sensorless drive method breaks through the chronic problem of the sensorless BLDC motor drives, lack of low speed operation, so that it ensures highly accurate, robust sensorless operation from near zero to high speed. For this purpose, a physically insightful, speed-independent function, based on a new flux linkage function, is used. A simulation result of the proposed sensorless method is shown, and the result discussed. Also, the validity of the proposed method is verified through the experimental results. [64] H. W. Koertzen, "Impact of die sensing on cpu power delivery," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 451. This study is regarding power delivery to a desktop microprocessor. It shows the advantages and disadvantages of sensing the feedback signals of the voltage regulator at the silicon die of the CPU, compared to the current method of sensing it at the socket. The main advantage is that the response time of the voltage regulator is improved, without increasing the bandwidth of the feedback loop. The down side is that the tolerance band of the voltage regulator increases. In most cases the net benefit of die sensing is positive, resulting in increased microprocessor performance at no additional cost. Simulated and measured results are presented. [65] H. Krishnamurthy, G. Narayanan, R. Ayyanar, and V. T. Ranganathan, "Design of space vector-based hybrid pwm techniques for reduced current ripple," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 583. Switching sequence used by conventional space vector PWM (CSVPWM) involves equal division of zero vector time between the two zero states in every subcycle. The sequences employed by bus-clamping PWM involve use of only one zero state in a subcycle. This paper deals with two sequences, which use only one zero state and involve division of active vector time within a subcycle. A novel hybrid PWM technique, employing these two sequences in conjunction with the conventional sequence, is proposed. The proposed PWM technique is designed using the notion of stator flux ripple. A procedure is presented for designing hybrid PWM techniques involving multiple sequences for reduced current ripple. The proposed PWM technique results in reduced current ripple over CSVPWM at higher modulation indices. Experimental results on a 2hp prototype induction motor drive are presented. [66] E. Lam, R. Bell, and D. Ashley, "Revolutionary advances in distributed power systems," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 30. Rising power demands and increasing number of supply voltages required in modern communications and computing systems are driving advancements in distributed power architectures. Primary-side isolated 48V power modules have matured with Single and Dual-outputs (+3.3V and +5V) achieving ultra-high density and greater efficiency. Secondary-side PWM controllers have evolved to higher frequency and efficiencies and are giving way to yet another distributed power concept, the quasi-regulated +12V single-output power module. Several power module manufacturers are now offering this new +12V Brick driven by demands from the system OEMs. In this paper we explore ever changing distributed power architectures, integrated PWM circuitry and new distributed power supply topologies that are enabling new information infrastructure systems. [67] E. Landsman, "Scalable data center architecture for on- demand power infrastructure," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 10. The present design of the power infrastructure of the typical data center in use today is hopelessly outdated. Because knowledge of the ultimate power demand is not known when the design is done, a lot of assumptions are made, and most systems are oversized. The result is waste of capital investment because of over sizing, waste of space, increased building time, lower reliability, lower electrical efficiency (typical installation is only 35% loaded), high engineering costs because every system is unique, and complex systems which are hard to repair. [68] H. Lavric and J. Nastran, "A hybrid voltage amplifier for power calibrator with harmonics analysis capability," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 925. The paper describes a voltage amplifier that is capable of accurate amplifying voltages up to 300 V rms within the frequency range from 40 Hz to 70 Hz with or without the presence of higher harmonics. Its sophisticated topology consists of a supreme linear amplifier and an inner hybrid power amplifier with an output transformer. The hybrid power amplifier, which acts as a self-oscillating system, is composed of a superior three-stage class AB amplifier and an inverter. The later provides a full load current while the former filters the waveform ripple. In this way a power efficient system is obtained whose efficiency at a full output power exceeds 90%. [69] B. K. Lee, J. P. Hong, and M. Ehsani, "Generalized design methodology of reduced parts converters for low cost bldc motor drives," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 277. Various reduced parts convertors were proposed for the two-phase brushless DC (BLDC) motor and a generalized design methodology was established for the multi-phase motor. As the examples of multi-phase BLDC motors, the four-phase and five-phase were considered in the study. It was found that a four-phase BLDC motor could be operated as two of a two-phase BLDC motor with modification of winding connection. This meant that only four switches were enough to drive a four-phase BLDC motor. [70] D.-Y. Lee, H.-J. Noh, D.-S. Hyun, and I. Choy, "An improved mppt converter using current compensation method for small scaled pv-applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 540. An improved MPPT converter with current compensation method for small-scaled PV-applications is presented in this paper. The proposed method implements maximum power point tracking (MPPT) by variable reference current which is continuously changed during one sampling period. Therefore, the proposed MPPT converter with current compensation method increases the power transferred to the load above 9%. As a result, the utilization efficiency of Photovoltaic (PV)-module can be increased. In addition, as it doesn't use digital signal processor (DSP), this MPPT method has the merits of both a cost efficiency and a simple control circuit design. Therefore, it is considered that the proposed MPPT method is proper to low power, low cost PV-applications. The concept and control principles of this improved MPPT method are explained in detail and the validity of the proposed method is verified through several simulated results. [71] K. Lee, K. Yao, X. Zhang, Y. Qiu, and F. C. Lee, "A novel control method for multiphase voltage regulators," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 738. This paper proposes a novel control method for the multiphase voltage regulators (VRs) to power the next generation of microprocessors. With a simple structure, this control can achieve multiphase current sharing, very fast transient response, and adaptive output voltage regulation. Simulation and experimental results show that the proposed control scheme significantly improves the performance, as compared with existing control methods. [72] K.-B. Lee, J.-H. Song, I. Choy, and J.-Y. Yoo, "An inertia identification using roelo for low speed control of electric machine," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1052. A new scheme to estimate the moment of inertia in the motor drive system in very low speed is proposed in this paper. The simple speed estimation scheme, which is usually used in most servo system for low speed operation, is sensitive to the variation of the machine parameter, especially the moment of Inertia. To estimate the motor Inertia value, Reduced-Order Extended Luenberger Observer (ROELO) is applied. The effectiveness of the proposed ROELO is applied by simulations. [73] T. Lequeu, D. Magnon, G. Kalvelage, and P. Aubin, "Study and application of an innovating topology of converter: Sparc - serial and parallel auto regulated configuration," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1070. Gerard KALVELAGE and Philippe AUBIN (patentees of the SPARC patent) of the FAIVELEY Transport company propose a new topology of insulated converter. Two converters, one on the primary side (input) and a second one on the secondary side (output), allow to combine several transformers in series (for high voltage) and/or in parallel (for high current). Mixed combinations are also possible (voltage and current of middle magnitude). The converters used have a "ladder" structure, thus distributing the voltage and/or the current in the switches. A particular control mode ensures an alternating voltage at the transformer terminals. Indeed a circular shift of the instructions sent to the switches leads to various kinds of commutations, such as a hard-switching with voltage and current divided by two: the commutation losses will therefore be reduced by a factor of 4. The interlacing of the switches' orders removes the discontinuities in the input and output electric signals, which present a weak ripple signal at high frequency, reducing the size of the associated filters. The principle of operation is illustrated together with steady state analysis. Moreover, the effectiveness of the proposed converter topology is verified by implementing a 5 kW-20 kHz prototype using IGBTs and fast recovery diodes. [74] D. Li, X. He, and Y. Deng, "High reliable power electronic system design based on bionics," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 471. This paper proposes a novel bionic approach for enhancing reliability of power electronic system by utilizing some principles including autonomous decentralized architecture, redundPOST http://216.228.1.34/authrev/RevuploadRese inspired from human body system. The application of bionics in power electronics is innovative from the methodological point of view. Finally, a single phase full-bridge power inverter based on autonomous decentralized architecture is investigated. The investigated inverter has advantages in reliability, flexibility and user-friendliness compared to conventional centralized power converters. The proposed autonomous decentralized architecture in this paper has a promising prospect and paves the way towards future Plug and Play power electronic systems for so many significant advantage. [75] P. Li and B. Lehman, "A simple design for paralleling current-mode controlled dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 898. This paper proposes a new current sharing method. It utilizes the inner current loops of current mode controlled converters to achieve the current sharing, and decouples control loops from the voltage regulation and current-sharing regulation instead of adding control loops as in traditional master-slave methods. Therefore, the performance is guaranteed in both the large and small signal sense. This is verified by experimental results. [76] Y. P. Li, F. C. Lee, and D. Boroyevich, "Igbt device application aspects for 50-kw zero-current-transition inverters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 518. This paper addresses two application aspects of IGBT devices for two different types of three-phase zero-current-transition (ZCT) soft-switching Inverters, which are built with SO-kW power rating for electric vehicles (EV) traction motor drives. One aspect is the characterization of main IGBTs under different ZCT conditions, for which switching loss reductions are quantified, and variations of soft-switching behaviors and mechanisms under different resonant tank designs are investigated and compared. The other is the selection and characterization of auxiliary switches. From the analysis on the unique operation conditions of the auxiliary switches, it is concluded that the current ratings specified for commercial IGBTs can not meet the requirements for the auxiliary switches. Accordingly, methods to select and characterize suitable auxiliary switches are proposed, and IGBTs from different manufacturers are tested and compared using the proposed methods. Hardware implementation and experimental results of the 50-kW prototypes are provided. [77] Z. X. Liang, F. C. Lee, J. D. Van Wyk, D. Boroyevich, E. Scott, J. Chen, B. Lu, and Y. Pang, "Integrated packaging of a 1kw switching module using planar interconnect on embedded power chips technology," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 42. A 1 kW MOSFET half-bridge switching subassembly with gate drivers has been designed and fabricated, in integrated three-dimensional (3-D) form factor, using a planar integration technology, through building up dielectric/metallization thin-film interconnection directly on co-planar bare power chips embedded in a ceramic carrier. The 3-D geometrical layout was optimized through simulating electrical and thermal performance, with Maxwell Q3D and I-DEAS, respectively. The advantages of this module have been experimentally demonstrated by the electrical and thermal performance in the testbeds and IPEM-based DC/DC converter. [78] C. C. Liaw, C. M. Liaw, H. C. Chen, Y. C. Chang, and C. M. Huang, "Robust current control and commutation tuning for an ipmsm drive," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1045. The operating performance improvement of an Interior permanent magnet synchronous motor (IPMSM) drive via robust current control and intelligent commutation tuning is studied in this paper. First, the nominal motor parameters are estimated and a robust current control scheme is designed to possess close and robust winding current tracking performance. It is known that the torque generating capability of an IPMSM is affected by the changes of commutation instant and field excitation. The proof is given to show that the latter can be equivalently achieved by tuning the commutation instant, and the effects of these two variations on the IPMSM drive performances under speed open-loop and closed-loop conditions are observed analytically and experimentally. Then accordingly, an intelligent tuning approach is developed to automatically determine the advance of commutation instant. The minimum current command is achieved to obtain better torque generating capability equivalently. A DSP-based IPMSM drive is established and the effectiveness of the proposed control approaches is demonstrated experimentally. [79] A. Lidow and G. Sheridan, "Defining the future for microprocessor power delivery," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 3. A brief review of the primary technical challenges confronting power management for the computing and information technology world was presented. The innovations in power semiconductor processes and device design were also elaborated. The changes in architecture and thermal management and the emergence of integrated solutions that would be needed to meet these power management challenges were also analyzed. [80] M. Liserre, A. Dell'Aquila, and F. Blaabjerg, "Genetic algorithm based design of the active damping for a lcl-filter three-phase active rectifier," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 234. The use of a LCL-filter mitigates the switching ripple Injected in the grid by a three-phase active rectifier. However stability problems could arise in the current control loop. In order to overcome them a damping resistor can be inserted, at the price of a reduction of the efficiency. On the contrary the use of the active damping seems really attractive but it is often limited by the use of more sensors respect to the standard control and by the complex tuning procedure. This paper introduces a new active damping method that does not need the use of more sensors and that can be tuned using genetic algorithms. It consists of adding a filter on the reference voltage for the converter's modulator. The tuning process of this filter is easily done, for a wide range of sampling frequencies, with the use of genetic algorithms. This method is used only for the optimum choice of the parameters of the filter and an on-line implementation is not needed. Thus the resulting active damping solution does not need new sensors or complex calculations. Moreover, in the paper particular attention is devoted to the dynamics of the system due to the introduction of the active damping. [81] C. Liu, F. Teng, C. Hu, and Z. Zhang, "Lclc resonant converter for multiple lamp operation ballast," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1209. This paper presents a design methodology, analysis, and practical considerations of LCLC resonant converter for multiple lamp operation ballast. According to the basic requirements of multiple lamp operation ballast (MLOB), the design procedure can be outlined to determine resonant parameter. Consequently, independent MLOB can be achieved under voltage-source half-bridge LCLC resonant converter with zero voltage switching (ZVS). Finally, some experimental results obtained from a prototype are shown to verify the theoretical discussion. [82] C. P. Liu, N. K. Poon, and M. H. Pong, "A low output ripple dc to dc converter topology using voltage overlapping technique," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 610. A new converter topology is proposed which uses voltage overlapping method with certain overlapping period that can theoretically provide smooth and regulated DC output voltage without the need of an output filter. An isolated DC/DC converter prototype with output voltage and current of 2.5V and 15A respectively was built to demonstrate its operation. Very low output ripple is observed. [83] J. Liu, T. G. Wilson Jr, R. Wunderlich, R. C. Wong, Q. Zhao, W. Dong, and F. C. Lee, "Large-signal model of a downstream dc/dc converter for analysis and design of front-end pfc rectifier using computer simulation," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1002. For large-signal analysis and design of power supply system with multiple converters, the simulation speed becomes much critical when simulation is employed as virtual prototyping approach. Previously published models for downstream DC/DC converters at the power semiconductor switch level or even the power stage level can hardly meet this requirement. This paper proposes a model that can accurately emulate the input characteristics of downstream DC/DC converters under low frequency small-signal situation or large-signal process. The model is very simple, which makes simulation very fast, therefore can greatly facilitate the design and verification of front-end PFC voltage loop compensator, and the analysis and design of many PFC transient issues in distributed power systems. [84] W. Liu, Q. Song, X. Xie, Y. Chen, and G. Yan, "6kv/1800kva medium voltage drive with three-level npc inverter using igcts," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 223. This paper presents a 6kV motor drive consisting of a 24-pulse rectifier and a three-level neutral-point-clamped (NPC) inverter using IGCTs. It is suitable for feeding standard industrial motors. Experimental results from the industrial installation show that the design and the implementation are successful. [85] P. C. Loh, D. G. Holmes, Y. Fukuta, and T. A. Lipo, "A reduced common mode hysteresis current regulation strategy for multilevel inverters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 576. This paper presents a new hysteresis current regulation technique with reduced common mode switching for three-phase multilevel inverters. The proposed technique uses three Independent multilevel hysteresis current regulators to generate three sets of complementary gating signals through the comparison of the measured current errors with implemented hysteresis limits. These gating signals are then distributed to each complementary switch pair of the multilevel inverter structure to switch with reduced common mode voltage. Additionally, by intelligently compensating for transition delays during dead-times, common mode voltage can essentially be eliminated completely. Two versions of the common mode regulation technique are derived by using either the line currents or differences between the line currents, known as delta currents, as the control variables. A detailed investigation is presented to determine that the delta currents are the optimal control variables. The performance of the proposed strategy is confirmed through both simulation and experimental investigations. [86] T. Lopez, G. Sauerlaender, T. Duerbaum, and T. Tolle, "A detailed analysis of a resonant gate driver for pwm applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 873. Gate drivers generate significant losses, especially at high frequencies. While conventional solutions dissipate all the energy, resonant gate drivers partly recover it. A resonant gate driver is studied in detail with the emphasis on PWM operation. Compared to other resonant drivers, the investigated driver combines simplicity, fast switching and loss reduction. Advantages and limits are discussed using a mathematical model and a prototype. [87] B. Lu, W. Dong, Q. Zhao, and F. C. Lee, "Performance evaluation of coolmos [trademark] and sic diode for single-phase power factor correction applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 651. The low conduction loss and switching loss characteristics make CoolMOS [trademark] and SiC diode attractive for the single-phase CCM PFC converters. In this paper, based on the device level and converter level evaluation, the loss reduction capability of the CoolMOS [trademark] and SiC diode is quantified. In addition, for the first time, a successfully operating 1kW 400KHz single-phase CCM PFC is demonstrated by using CoolMOS [trademark] and SiC diode. [88] J. Luo, N. Pongratananukul, J. A. Abu-Qahouq, and I. Batarseh, "Time-varying current observer with parameter estimation for multiphase low-voltage high-current voltage regulator modules," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 444. Current sharing in interleaved converters is an essential issue for low-voltage, high-current Voltage Regulator Modules (VRMs). The most common method is to sense the average voltage across low-side switches to obtain phase currents. In this paper, an instantaneous current sensing method is presented to observe instant load current and phase currents for multiphase buck converter. Since the load value is time varying, an adaptive control method is applied to estimate load changing. The proposed current observer can also be used for other topologies requiring current sensing. A digital observer is designed and implemented using a DSP controller. [89] S. Luo, L. Hua, H. Mao, and I. Batarseh, "A high-frequency ac distributed power system with dual pwm buses," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 63. A high-frequency (HF) AC distributed power system (DPS) with dual PWM buses is presented. Experimental prototype with a total of 210W output power for three Independent outputs, i.e, 3.3V@30A, 5.0V@10A, and 12V@5.1A, was built to verify the concept presented in this paper. The experimental results demonstrate that the proposed system works well and the around 80% efficiency, which is 3% higher than that from single bus DPS under same operation conditions, can be obtained. [90] J. H. Ly and K. Siri, "Frequency response analysis for dc-dc converters without small-signal linearization," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1008. Presented herein is a frequency-domain analysis approach using Matlab Simulink models via Fast Fourier Transform (FFT) of dc-dc converter closed-loop systems without small-signal linearization. Two modeling techniques are used: 1) Average large-signal model; 2) Pulse-by-pulse switching. It is shown that the frequency response result obtained with the Matlab Simulink and PSPICE model using average large-signal technique is comparable. Moreover, contrary to using PSPICE, obtaining frequency response using FFT via the Matlab Simulink model with the pulse-by-pulse switching method is easy and straightforward. The reason is that Matlab can accommodate script files for repetitive simulation data processing, whereas PSPICE cannot. Frequency domain analysis on the dc-dc converter model using the pulse-by-pulse switching technique leads to a more accurate result since all non-linear elements in the circuit are included. The proposed "software analyzer approach" is demonstrated and validated with a converter power system operating in the solar-array voltage regulation mode. [91] L. L. Macomber, "Reduce capacitor count 50% in bus-capacitor arrays using new electrolyte," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 764. The use of a new electrolyte in reducing the capacitor count in bus-capacitor arrays is discussed. The electrolyte permit the capacitors' internal temperature to be 70 ° C above ambient, and thus permit doubling the ripple current per capacitor. It is shown that the new electrolyte for the aluminum electrolytic bus capacitors can eliminate the need for extra capacitance and reduce the capacitor count by 50%. [92] R. Malik, "The power system challenge - understanding the total picture," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 202. The designing of an optimal power system was discussed. Various issues and trade off for designing a power system specifically for server applications were also studied. It was found that it is the responsibility of the power system designer to have in-depth knowledge of the server system and future technology to produce a cost effective power system. [93] H. Mao, J. A. Abu-Qahouq, S. Deng, and I. Batarseh, "A new duty-cycle-shifted pwm control scheme for half-bridge dc-dc converters to achieve zero-voltage-switching," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 629. Asymmetric control scheme is an approach to achieve ZVS for half-bridge isolated DC-DC converter. However, it is not suited for wide-range input voltage due to the uneven voltage and current components stresses. This paper presents a new "duty-cycle-shifted PWM control" scheme for half-bridge isolated dc-dc converters to achieve ZVS operation without asymmetric penalties and without adding additional components. Because the duty cycle width is kept identical for both switches, the asymmetric current and voltage stresses problem is eliminated. The principles of operation and key features are illustrated. Experimental results verify that higher efficiency is achieved with the proposed "duty-cycle-shifted" control method, especially at higher switching frequency. [94] H. Mao, J. A. Abu-Qahouq, S. Luo, and I. Batarseh, "New zero-voltage-switching half-bridge dc-dc converter and pwm control method," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 635. This paper presents a new half-bridge isolated dc-dc converter topology associated with a new PWM control method to achieve zero-voltage-switching (ZVS) of all switches. Switching losses and losses related to transformer leakage inductance are significantly reduced, which provides converter with the potential to operate at higher efficiency and higher frequency. The principle of operation and features of proposed topology are illustrated and experimentally verified. [95] M. I. Marei, E. F. El-Saadany, and M. M. A. Salama, "An intelligent control for the dg interface to mitigate voltage flicker," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 179. Distributed Generation (DG) is used widely in the modern distribution systems. This paper proposes a novel functionality of the interface between DG and the utility network to mitigate the voltage flicker and regulate the voltage at the Point of Common Coupling (PCC) along with its main function of controlling the power flow. The voltage leveling is achieved by tracking its envelope utilizing an intelligent control based on ADAptive LINEar neuron (ADALINE). One of the advantages of the proposed control is its insensitivity to the parameter variation, which is vital for distribution system applications. Extensive simulation of the proposed DG interface is conducted to evaluate the performance of the proposed control algorithm for multifunction operation. [96] N. Mi, B. Sasic, J. Marshall, and S. Tomasiewicz, "A novel economical single stage battery charger with power factor correction," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 760. A single stage AC-DC topology with power factor correction is proposed for battery charger applications. Desired features for battery charger such as low cost, fast charging, charge profile programmability, high efficiency and high reliability are fully achieved by means of proposed solution. Additionally, its multiphase operation configuration provides easy power scaling. The proposed approach is superior to conventional ferro-resonant regulation widely used for EV (Electrical vehicle) charger applications. It is especially suitable to low cost and high power applications. The feasibility and practical value of the proposed approach are verified by the experimental results from a 1 kW product prototype. [97] B. Miller, "Conference proceedings - ieee applied power electronics conference and exposition - apec: Foreword," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. [98] B. Miller, "Conference proceedings - ieee applied power electronics conference and exposition - apec: Foreword," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. [99] J. M. Miller, "Power electronics in hybrid electric vehicle applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 23. Hybrid electric vehicles are enjoying more widespread customer acceptance than battery electric vehicles because of their performance and economy. Today two of the major global automotive companies have hybrid electric vehicles for sale in most areas of the globe with cumulative sales now exceeding 120k. Whereas battery electric vehicles may find niche applications in route travel and short commuting the hybrid electric vehicle provides un-compromised utility and fuel economy benefits ranging from 5% to 50% or higher compared to the non-hybrid base vehicle. Ac drives are now ubiquitous in hybridized power trains due to their high durability and ease of control via power electronics. However, because of the unique application requirements of an automotive propulsion system the present ac drives are still inadequate in meeting the full drive system performance requirements and package volume targets. Consequently, today's hybridized power trains continue to utilize ac drives that have either over rated electric machines or power electronics or both. This paper is motivated by the premise that the most economical solution to wide CPSR and overall performance of ac drives for hybrids rests on power electronics. The paper will describe the present situation and what efforts are underway, principally in transmission systems, to provide ac drives that are better matched to personal transportation vehicles. [100] A. Monti, R. Dougal, E. Santi, D. Li, and K. Proddutur, "Compensation for step-load variations when applying synergetic control," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 334. The theory of synergetic control was introduced in a power electronics context in a previous paper. In this paper we review the theory, then focus on some practical aspects with reference to both simulations and actual hardware. In particular we address step load response and we experiment with several different approaches. Adaptive and other control laws are introduced to improve the control performance. A small-signal analysis is presented, which allows prediction of closed-loop response time. [101] J. T. Mossoba and P. T. Krein, "Design and control of sensorless current mode dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 315. Sensorless current-mode (SCM) control of dc-dc converters is a feed forward open loop scheme, which is compared to peak current-mode (PCM) control. Small signal model simulations of each controller are validated by experimental results. SCM offers improvement over the line disturbance rejection of current-mode control without feedback or current sensing. SCM is demonstrated to be useful in both open loop and closed loop configurations, by exploiting its inherent reference tracking and line disturbance rejection. In contrast, PCM requires high gain two-loop control for voltage regulation. [102] J. J. Nelson, G. Venkataramanan, and A. M. El-Refaie, "Fast thermal profiling of power semiconductor devices using fourier techniques," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1023. Accurate prediction of temperature variation of power semiconductor devices in power electronic circuits is Important to obtain optimum designs and estimate reliability levels. Temperature estimation of power electronic devices has generally been performed using transient thermal equivalent circuits. In the presence of varying load cycles, it has been typical to resort to a time domain electrical simulation tool such as P-Spice [trademark] or SABER [trademark] to obtain a time series of the temperature profiles. However, for complex and periodic load cycles, time series simulation is time consuming. In this paper, a fast Fourier analysis based approach is presented for obtaining temperature profiles for power semiconductors. The model can be implemented readily into a spreadsheet or simple mathematical algebraic calculation software. The technique can be used for predicting lifetime and reliability level of power circuits easily. Details of the analytical approach and illustrative examples are presented in the paper. [103] C. Nesgaard, "An array-based study of increased system lifetime probability," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 476. A redundancy control scheme, which is based on the array technology that increases the overall reliability quite considerably was discussed. To provide feedback to the redundancy control system, each block in the overall power system can take on two different logic values. Results showed that a considerable increase in system survivability was possible when the proposed array-based control and implementation technique was applied. [104] E. R. Olson and R. D. Lorenz, "Integrating giant magnetoresistive current and thermal sensors in power electronic modules," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 773. Motor drive technology relies on power electronic devices and current sensors for motor control. With active thermal control of IGBT junction temperatures, the reliability and full utilization of power devices can be improved. The intent of this research is to introduce the module-level integration of the GMR field detector as both a current and temperature sensor. The integration effort also includes a new type of flexible planar interconnect to replace conventional wire bonds. The integration goal is to improve the reliability and lower the cost of motor drive systems. Cost and reliability will benefit from a lower parts count and fewer interconnections. Because of the small size, inherent galvanic isolation, temperature dependence, high sensitivity and bandwidth, the magnetoresistive field detector offers promising options for both integrated current and temperature sensing methods. This research describes the operation of GMR, as well as the necessary signal conditioning circuitry for integrated current and temperature sensing. The measured performance attributes of the sensor are also shown. Finally, future plans are discussed which involve combining the current and temperature sensing capabilities with the design of an interconnect layout and observers for junction temperature estimation. [105] V. M. Pacheco, L. C. Freitas, J. B. Vieira Jr, E. A. A. Coelho, and V. J. Farias, "Stand-alone photovoltaic energy storage system with maximum power point tracking," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 97. This digests deals with the study of a stand-alone photovoltaic system, which is able to extract the maximum power from photovoltaic array for all solar intensity conditions and to provide output voltage regulation. The proposed system consists of a dc-dc converter in combination with battery energy storage in a simple structure. Operating principle and control strategy are described. Digital simulation is included, supporting the validity of the concept. [106] J.-H. Park and B. H. Cho, "The zero voltage switching(zvs) critical conduction mode(crm) buck converter with tapped-inductor," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1077. This paper proposes a critical conduction mode buck converter that has soft-switching operation by tapped-inductor. In this converter, both the active switch and the diode have soft switching operation by the resonance between the switch parasitic capacitors and the filter inductor. And, the turn-off switching loss of the active switch is reduced by the decrease of the turn-off current. In addition, tapped-inductor changes the conduction operation, which makes some advantageous conditions that diminish the conduction loss and device stresses. Therefore, this topology, ultimately, achieves both the power and cost efficiency by the simple variation of the classical structure. For the proposed converter evaluation, this paper provides the operation analysis of the converter and the hardware verification by 50W prototype operating at maximum 70kHz. [107] S. Park and T. M. Jahns, "A self-boost charge pump topology for a gate drive high-side power supply," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 126. A self-boost charge pump topology is presented for a floating high-side gate drive power supply that features high voltage and current capabilities for use in Integrated Power Electronic Modules (IPEMs). The transformerless topology uses a small capacitor to transfer energy to the high-side switch from a single power supply referred to the negative rail. Unlike conventional bootstrap power supplies, no switching of the main phase-leg switches is required to provide power continuously to the high-side gate drive, even if the high-side switch is permanently on. Additional advantages include a low parts count and simple control requirements. A piecewise linear model of the self-boost charge pump is derived and the circuit's operating characteristics are analyzed. Simulation and experimental results are provided to verify the desired operation of the new charge pump circuit. [108] S.-I. Park, T.-S. Kim, S.-C. Ahn, and D.-S. Hyun, "An improved current control method for torque improvement of high-speed bldc motor," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 294. The BLDC (Brushless DC) motor is characterized by linear torque to current and speed to voltage. It has low acoustic noise and fast dynamic response. Moreover, it has high power density with high proportion of torque to inertia In spite of small size drive. However, at high-speed operation, torque and speed response characteristic is deteriorated by the motor inductance components in stator windings. It is difficult that the BLDC motor is used to the Industrial application requiring a wide range of operating speeds. Phase advance angle control method of different methods used to improve torque and speed response is used widely at high-speed operation. However, conventional phase advance angle control method was considered about forward motoring mode. Therefore, position Information error of rotor that reverse motoring mode has phase lag angle of double comparing with forward motoring mode is occurred. Consequently, torque performance is destroyed significantly. In this paper, a control method using adjustment of the phase advance angle is proposed. This proposed method improves the torque and speed response characteristic by minimizing delay of current at high-speed operation. Simulated results prove the effectiveness of the proposed method through comparison with the conventional control method. [109] M. Pavier, A. Sawle, A. Woodworth, R. Monteiro, J. Chiu, and C. Blake, "High frequency dc:Dc power conversion: The influence of package parasitics," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 699. Operating power MOSFET devices at frequencies over 1MHz will pose significant challenges to established power electronic packages such as the D2-Pak and wirebonded SO-8 devices. In this paper the high frequency parasitic impedances of a range of power electronic packages are presented. Results show that a source mounted power package technology based upon a copper clip type assembly has considerably lower parasitic impedance compared to conventional power packaging at frequencies in the range of 500KHz to over 1MHz. The resistance of conventional packages recorded over this range of frequencies increases significantly as the frequency approaches 1Mhz. This is expected to be a result of skin effect related phenomena occurring in wire bonds and package leads. Package impedance data up to frequencies of 5MHz will be presented for a range of packages along with efficiency data recorded from devices operating in multi-phase buck converter circuits. [110] L. Petersen and R. W. Erickson, "Reduction of voltage stresses in buck-boost-type power factor correctors operating in boundary conduction mode," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 664. In this paper a new converter is proposed for universal line PFC operated in Boundary Conduction Mode. The proposed Modified SEPIC enables the use of lower voltage rated semiconductors compared to other single-switch buck-boost derived topologies with a resulting performance comparable to the boost topology. The operation and the design procedure is described in detail and the proposed converter is experimental verified with a 210V, 100W prototype for the universal line input (90Vac-270Vac). [111] J. E. Piatt, "Application of the dell direct model to the ac inverter market," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 209. In this paper, I examine the application of a direct-business model to a predominantly indirect market. Currently, the majority of inverter sales are completed through an indirect sales channel, utilizing the services of distributors. After careful analysis of the Inverter market and a leading direct-marketing manufacturer in the electronics industry, I have developed several conclusions that maximize the effectiveness of sales efforts in the inverter market. Most important to the sales success of Inverter manufacturers is the willingness to Identify areas of outsourcing and to identify partners for such efforts. A careful distinction between OEM and end-user sales must be made. Ideally, a partner that can directly market to OEMs without interference from distributors should be identified. [112] J. D. Pollock, T. Abdallah, and C. R. Sullivan, "Easy-to-use cad tools for litz-wire winding optimization," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1157. Existing advanced and powerful techniques for optimizing litz-wire winding designs are complex and usually require using multiple expensive software packages. A new CAD tool has been created to make advanced litz-wire design methods available to any designer through an easy-to-use web interface. The software performs two-dimensional field simulations and returns designs optimized considering cost and loss. It is shown that simple fullbobbin designs, compared to optimized choices, can result in much higher loss with almost no cost advantage or much higher cost with almost no loss advantage, whereas the optimization results provide a full range of choices providing the lowest loss at any given cost or the lowest cost at any given loss. [113] N. K. Poon, C. P. Liu, and M. H. Pong, "A zvs approach for ac/dc converter with pfc," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 684. Other than integrating the PFC and the DCDC converter, this approach resort to the conventional two stage design with constant operating frequency and ZVS for all switches. A small switch is added between the PFC and asymmetric half bridge DC/DC converter to produce a four switch AC/DC converter with PFC. A 91% efficiency 12V 10A universal off line ACDC adapter is built to demonstrate its merits. [114] A. Prodic, D. Maksimovic, and R. W. Erickson, "Digital controller chip set for isolated dc power supplies," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 866. This paper describes a digital controller chip set for high-frequency DC-DC power converters with galvanic isolation. The secondary-side controller includes an A/D converter and a transmitter that sends a digital error signal as serial data through an opto-coupler. The primary-side controller includes a serial-data receiver, a programmable digital FID regulator, and a high-resolution (10-bit) digital pulse-width modulator. The digital error signal transmission through the isolation boundary eliminates the problem of gain variation when the opto-coupler is used in linear mode. The chip set is tested as a replacement for a conventional analog current-mode controller in a 3.3 V, 20 A, 400 KHz DC power supply. Experimental results with the digital controller show improved dynamic responses compared to the responses obtained with the analog controller. [115] A. Prodic, D. Maksimovic, and R. W. Erickson, "Dead-zone digital controller for improved dynamic response of power factor preregulators," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 382. This paper presents a simple control method for improvement of dynamic responses in a digitally controlled low-harmonic rectifier with power factor correction (PFC). The controller uses a fixed or self-adjusting dead zone in analog-to-digital conversion to eliminate the output capacitor ripple from the voltage control loop. The proposed control methods are tested in a completely digitally controlled 200 W boost PFC operating at 200 kHz switching frequency. Experimental results show that the simple controller implementation results in low current harmonics and significantly improved output voltage transient responses. [116] H. Qi and Y. Gao, "A novel si<sub>1-x</sub>ge<sub>x</sub>/si hetero-junction power diode for the fast-s witching and the soft recovery," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 964. A novelp<sup>+</sup>(Si<sub>1-x</sub>Ge<sub>x</sub>)-n<sup>-</sup>-n<su p>+</sup> hetero-junction power diode which has the gradual changing doping concentration in the n<sup>-</sup>-region is proposed. The device characteristics were simulated and the optimal design was given. From the result, it can be shown that the fast-switching and the soft recovery characteristics of the device are much improved but not notable changed in forward drop. The optimal design of the Ge percentage and the trade-off of the n<sup>-</sup>-region thickness for the fast-switching and the soft recovery are given. [117] Z. Qian, F. Z. Peng, J. M. Zhang, and X. G. Xie, "A 30v/1mhz ac/ac converter for high frequency ac distributed power system applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 795. This paper presents the design considerations for an AC/AC converter for high frequency AC Distributed Power System (DPS) applications. The developed circuit features simple structure and control strategy, high efficiency with sine wave output. A low power loss startup circuit for two stage converter is also proposed in this paper. Experimental results from a 200VA 30VAC/1MHZ converter with efficiency of 90% confirm the validity of the theoretical analysis. [118] Y. Ren, M. Xu, Y. Meng, and F. C. Lee, "A novel quasi-resonant phase-shifted full-bridge converter for 48 v power pods," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 420. This paper proposes a novel quasi-resonant phase-shifted full-bridge (QR-PS-FB)* for high-frequency 48 V power pods. The topology can achieve a complete lack of body diode loss. It can also achieve soft switching at primary switches. Besides that, it can significantly reduce the ringing without any additional components. The theoretical analysis and simulation waveforms are provided. 1 MHZ, 1.2 V/70 A hardware is built and experimental results are also provided. [119] Y. Ren, M. Xu, K. Yao, and F. C. Lee, "Two-stage 48 v power pod exploration for 64-bit microprocessor," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 426. In this paper, a new two-stage structure is proposed. For the first stage, a concept of energy transfer by the leakage inductor combined with the resonance is used to achieve a simple, high efficiency isolation stage. Application of this concept leads to the discovery of a family of simple, high efficiency DC/DC transformers. In order to achieve optimal system performance, the intermediate bus voltage is also investigated. Finally, The experimental results are provided. [120] J. Ribas, J. M. Alonso, A. J. Calleja, E. Lopez, J. Cardesin, J. Garcia, and M. Rico, "Arc stabilization in low-frequency square-wave electronic ballast for metal halide lamps," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1179. Discharge lamps present a negative dynamic characteristic that makes necessary using a current limiting element. In high frequency resonant ballasts current limitation is performed by the output resonant tank, but in low-frequency square-wave electronic ballasts arc stabilization is accomplished by the stage feeding the square wave inverter. Therefore, the design of the input converter must be made taking into account the lamp dynamic characteristic. In present paper a new procedure for obtaining the small-signal dynamic characteristic of metal halide lamps is proposed. Using the proposed methodology the small-signal characteristic of a 70W is obtained, this characteristic is then used for the design of an electronic ballast based on a buck-boost converter followed by a full bridge inverter. The limits for stable operation obtained are verified using a laboratory prototype. [121] J. I. Rodriguez and S. B. Leeb, "A multilevel inverter topology for inductively-coupled power transfer," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1118. This paper describes a multilevel inverter for delivering power to a set of frequency selectable induction heating targets for stimulating temperature sensitive polymer actuators. The proposed inverter topology overcomes the capacitor voltage balancing issue common to traditional multilevel inverters. This inverter is suitable for sustained real power transfer. [122] M. Saeedifard, A. R. Bakhshai, G. Joos, and P. Jain, "Modified low switching frequency space vector modulators for high power multi-module converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 555. Force-commutated PWM controlled multi-converter systems have been proposed for high power applications, particularly reactive power compensation and FACTS devices. Advantages of the space vector modulation make this PWM technique the prefered technique especially for high power applications. This paper presents new low switching frequency SVM strategies that lead to symmetrical and high quality output voltages fulfilling the high power application standards. Pattern generation options are analyzed and system waveforms are presented for different switching frequencies and number of modules. Results are validated by simulation and confirmed by experiments on a 5 kVA prototype unit. [123] M. Salo and H. Tuusa, "Experimental results of the current-source pwm inverter fed induction motor drive with an open-loop stator current control," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 839. In this paper the control of the current-source PWM inverter fed induction motor drive is discussed. The vector control system of the induction motor is realized in a rotor flux oriented reference frame, where only the measured angular rotor speed and the dc link current are needed for motor control. Methods to damp the stator current oscillations and to compensate the capacitive currents drawn by the load filter are presented. The proposed methods operate in an open-loop manner and can be realized without measurement of any electrical variable. With the presented open-loop control methods the motor current sensors can be totally eliminated since the stator current measurements are not needed either for protection in the current source inverter fed drives. The proposed control methods are realized using a single-chip Motorola MC68HC916Y1 microcontroller. The experimental tests show excellent performance in both steady state and transient conditions. [124] M. Sanz, P. Alou, A. Soto, R. Prieto, J. A. Cobos, and J. Uceda, "Magnetic-less converter based on piezoelectric transformers for step-down dc/dc and low power application," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 615. This paper presents a very simple step-down DC/DC low power converter based on Piezoelectric Transformers (PTs) without any magnetic component. PTs become very interesting in this kind of applications comparing with magnetic transformers due to the higher power density. It is important to highlight that the PT has been specifically designed to avoid the use of magnetic components. Dynamic response of the power stage with the PT is analyzed, achieving a 2.5 kHz bandwidth. The use of a PT allows a wide input voltage range (20 V - 75 V), 3 V, 1 W DC/DC converter. [125] M. P. Sayani and J. Wanes, "Analyzing and determining optimum on-board power architectures for 48v-input systems," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 781. An optimum on-board power architectures for 48V-input systems was analyzed. The trade-offs in size, efficiency and cost of these on-board power architectures were explored. An intermediate bus approach with a wide-range input, regulated bus converter involved a premium in cost, space and power dissipation. [126] M. P. Sayani and J. Wanes, "Trends and drivers in isolated board-mounted dc/dc products for communications applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 37. The trends and driver isolated board-mounted DC/ DC products for communications applications were discussed. An exploration of the technology trends in communications end applications and the impact on the Board-Mount Power (BMP) market was performed. A brief review of the key drivers of efficiency within a BMP and enablers to progress in this dimension was also presented. [127] F. Schafmeister, S. Herold, and J. W. Kolar, "Evaluation of 1200v-si-igbts and 1300v-sic-jfets for application in three-phase very sparse matrix ac-ac converter systems," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 241. In this paper based on experimental investigations of the power semiconductor switching behavior and on analytical calculations the conduction and switching losses of a three-phase Very Sparse AC-AC Matrix Converter (VSMC) supplying a permanent magnet synchronous motor are discussed in detail. There, 1200V-Si-IGBTs/1200V-Si-ultra-fast-recovery diodes and 1300V-SiC-JFET/Si-MOSFET cascodes are employed for realizing the converter power circuit. The worst case operating conditions are identified and the efficiencies resulting in dependency of the switching frequency and load current amplitude are shown in graphical form. Furthermore, the operating range of the VSMC with respect to the maximum admissible junction temperature of the power semiconductors is determined. Finally, topics to be treated in the continuation of the research are discussed briefly. [128] M. J. Schutten, R. L. Steigerwald, and J. A. Sabate, "Ripple current cancellation circuit," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 464. A ripple current cancellation technique injects AC current into the output voltage bus of a converter that is equal and opposite to the normal converter ripple current. The output current ripple is ideally zero, leading to ultra-low noise converter output voltages. The circuit requires few additional components, no active circuits are required. Only an additional filter inductor winding, an auxiliary inductor, and small capacitor are required. The circuit utilizes leakage inductance of the modified filter inductor as all or part of the required auxiliary inductance. Ripple cancellation is independent of switching frequency, duty cycle, and other converter parameters. The circuit eliminates ripple current in both continuous conduction mode and discontinuous conduction mode. Experimental results provide better than an 80 X ripple current reduction. [129] D. Seyoum, M. F. Rahman, and C. Grantham, "Terminal voltage control of a wind turbine driven isolated induction generator using stator oriented field control," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 846. This paper presents the voltage build up process and terminal voltage control in an isolated wind powered induction generator driven by a variable speed wind turbine using stator flux oriented vector control. Here three-phase induction generator is excited using a PWM inverter/rectifier connected to a single capacitor on the DC side. Wind powered isolated induction generators have an input, wind, which is not controllable, but they can be set to operate within a given variation of speed. Unlike a grid connected induction generator, in an isolated induction generator there should be a control system that keeps the DC bus voltage at a constant value when the speed of the rotor is varied. The paper presents the control system to maintain the DC bus voltage at a constant value by varying the flux in the induction generator when the rotor speed is varied. During voltage build up the variation of magnetizing inductance is taken into consideration. [130] J. Shao, D. Nolan, and T. Hopkins, "Improved direct back emf detection for sensorless brushless dc (bldc) motor drives," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 300. Improved back EMF detection circuits for low voltage/low speed and high voltage sensorless BLDC motor drives are presented in this paper. The improvements are based on the direct back EMF sensing method from our previous research work described in reference [10], which describes a technique for directly extracting phase back EMF Information without the need to sense or re-construct the motor neutral. The reference method is not sensitive to switching noise and requires no filtering, achieving much better performance than traditional back EMF sensing scheme. A complementary PWM (synchronous rectification) is proposed to reduce the power dissipation in power devices for low voltage applications. In order to further extend the sensorless BLDC system to lower speed, a pre-conditioning circuit is proposed to amplify the back EMFs at very low speed. As a result, the brushless de motor can run at lower speed with the improved back EMF sensing scheme. On the other hand, another improved detection circuit is presented for high voltage applications to overcome the delaying problem caused by large sensing resistors. The detailed circuit models are analyzed and experimental results verify the analysis. [131] W. Shireen and R. A. Kulkarni, "A soft switching inverter module with modified dc-link circuit for high frequency dc-ac power conversion," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 507. This paper proposes an improved dc-link circuit for soft switching inverters with fewer components (two auxiliary switches) involving simpler control The operation principle and control arrangement of the modified dc-link circuit are explained. The experimental results from a 500 W laboratory prototype with a R-L load validate the operation of the proposed DC-link circuit. The modified DC-link circuit is then used to supply power to a single-phase full bridge PWM inverter with a 110 V, 60 Hz half horsepower capacitor start motor. Experimental results from the laboratory setup verify the feasibility of the proposed DC-link circuit in achieving soft switching in PWM inverters. [132] B. N. Singh and P. Rastgoufard, "A new topology of active filter to correct power-factor, compensate harmonics, reactive power and unbalance of three-phase four-wire loads," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 141. This paper proposes a new topology of an Active Filter (AF) with improved control algorithm. The reactive power theory of three-phase circuits is used to obtain reference currents as control quantities for the AF. The developed improved control algorithm is first tested with a standard topology of the AF, thereafter, extended to control a new topology of four-pole AF system. The new topology of the AF system is capable to compensate harmonics and reactive power, correct power-factor and unbalance in three-phase four-wire balanced/unbalanced linear/nonlinear loads. The proposed new topology of the AF system fully compensates neutral current for nonlinear unbalanced load connected in a three-phase four-wire supply system, thereby preventing heating and bursting of neutral conductor. The new topology of the AF system is free from shoot through fault and exhibits a desired performance. The developed control algorithm is implemented using a TMS320C31 DSP system and performance of new topology of the four-pole AF system with improved control algorithm is simulated. Simulation as well as experimental results are given and discussed in detail. [133] K. Siri and K. A. Conner, "Independently sourced parallel-connected power systems with maximum power tracking," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 533. Presented herein is a multiple-channel distributed Maximum Power Tracking (MPT) power system with channel outputs connected in parallel, and channel inputs connected to independent power sources. A "shared-bus" current-sharing method utilizing the distributed MPT control system is well suited to regulate parallel-connected current-mode dc-dc converters dedicated to each power channel. For broader applications with distributed solar-array sources, the distributed MPT approach was implemented to achieve robust stability. The approach was successfully validated through a two-channel 1500-W prototype, yielding nearly uniform current-sharing and reliable MPT performance. Each power channel was shown to track the array peak power from 50 W to 600 W with tracking efficiency of nearly 100%. The multiple-channel distributed-MPT power system provides ease of power expansion, stable current-sharing, fault-tolerance, and autonomous MPT control. [134] H. Song, Y. Yu, M. Yang, and D. Xu, "A novel smc-fuzzy speed controller for permanent magnet brushless dc motor," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 281. This paper presents a novel SMC-Fuzzy speed controller for permanent magnet brushless DC motor (BLDCM). The proposed controller employs only the signal of speed error, avoiding the sensitivity to the noise of the acceleration signal as in the conventional sliding mode controller (SMC). It is composed of an equivalent control term, a switching term and a fuzzy control term. The sliding mode controller that is made up of the former two terms ensures the system's stability. The SMC's chattering phenomenon is eliminated by varying its control continuously according to the distance of the system states from the sliding surface. While the fuzzy control term improves dynamic response and decreases the steady-state error in the boundary layer. Simulation results show the proposed controller is better than the conventional SMC controller with a boundary layer. The experimental results demonstrate the high performance of the proposed controller. [135] Q. Song, W. Liu, Q. Yu, X. Xie, and Z. Wang, "A neutral-point potential balancing algorithm for three-level npc inverters using analytically injected zero-sequence voltage," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 228. Based on the zero-sequence component of the reference voltages, this paper comprehensively analyzes the neutral-point variation and balancing control for three-level neutral-point-clamped inverter. An analytical method is proposed to accurately calculate the injected zero-sequence voltage for NP balancing. Based on the analytical analysis, the limitation of NP balancing control is revealed and the NP-fully-controllable region is presented. A real-time NP balancing algorithm is proposed as well. The feasibility of the proposed method is verified using simulation results for a 6kV/1800kVA medium voltage drive. [136] S.-H. Song, S.-I. Kang, and N.-K. Hahm, "Implementation and control of grid connected ac-dc-ac power converter for variable speed wind energy conversion system," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 154. 30 kW electrical power conversion system is developed for a variable speed wind turbine system. In the wind energy conversion system(WECS) a synchronous generator converts the mechanical energy into electrical energy. As the voltage and frequency of generator output vary along the wind speed change, a dc-dc boosting chopper is utilized to maintain constant dc link voltage. The input dc current is regulated to follow the optimized current reference for maximum power point operation of turbine system. Line side PWM inverter supply currents into the utility line by regulating the dc link voltage. The active power is controlled by q-axis current whereas the reactive power can be controlled by d-axis current. The phase angle of utility voltage is detected using software PLL(Phased Locked Loop) in d-q synchronous reference frame. Proposed scheme gives a low cost and high quality power conversion solution for variable speed WECS. [137] A. Soto, A. De Castro, P. Alou, J. A. Cobos, J. Uceda, and A. Lotfi, "Analysis of the buck converter for scaling the supply voltage of digital circuits," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 711. The energy consumption in mobile systems has become a big challenge that limits high performance and autonomy in mobile systems. The Dynamic Voltage Scaling (DVS) is a recent technique that reduces energy consumption varying dynamically the supply voltage of the system accordingly to the clock frequency. The Buck topology is a good candidate to supply step variations of the output voltage meeting the DVS requirements. In this paper, it is analyzed which is the fastest output voltage evolution that can provide the Buck topology. The minimum time state transition in the Buck converter and its corresponding control law are obtained applying the Maximum Principle or Pontryagin's Principle. Design criteria for the Buck topology are derived from this result. The analysis is extended to a multiphase Buck converter. The minimum time control law is validated in a prototype. The measurements are in good agreement with the theoretical results. [138] Y. Sozer and D. A. Torrey, "Closed loop control of excitation parameters for high speed switched-reluctance generators," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 75. This paper presents a new approach to the automatic control of excitation parameters for the switched-reluctance generator (SRG) where the SRG system operates at sufficiently high speed that it operates in the single pulse mode. The turn-on and turn-off angles are the two parameters through which we can control the electric power generation. The objective of the work is to develop an easily implementable control algorithm that automatically maintains the most efficient excitation angles in producing the required amount of electric power. The work is focused on finding the most efficient excitation angles and characterizing them for easy implemention under closed loop control, Through modeling of an experimental SRG and extensive simulation, it can be seen that the optimal-efficiency turn-off angles can be characterized as a function of power and speed level. Within the closed-loop power controller, the optimal-efficiency turn-off angle is determined from an analytic curve fit. The turn-on angle is then used as the degree of freedom necessary to regulate the power produced by the SRG. Given that the turn-off angle is associated with optimal-efficiency at each speed and power point, overall operation is achieved at optimal-efficiency. The SRG, inverter and control system are modeled in Simulink to demonstrate the operation of the system when implemented within a voltage regulation system. The control technique is then applied to an experimental SRG system. Experimental operation documents that the technique provides for efficient operation of the SRG system through tuning the controller at only four operating points. [139] D. Spillane, D. O'Sullivan, M. G. Egan, and J. G. Hayes, "Supervisory control of a hv integrated starter-alternator with ultracapacitor support within the 42 v automotive electrical system," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1111. In this paper, the development of an integrated starter alternator (ISA) system is described. The main system components are an induction machine drive system supplied by a high-voltage dc bus with ultracapacitor support and a high power dc/dc converter. The control of the induction machine, dc/dc converter and the overall supervisory control algorithm implemented on the ADMC330 DSP, are described. Having developed a functional integrated starter alternator, the relative merits of the technology are assessed. A comparison is made with a conventional starter motor during cranking. Timing diagrams illustrating DSP signals for an engine start-up sequence are also presented. [140] J. Sun, "Input impedance analysis of single-phase pfc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 361. Input impedance of single-phase boost power factor corrected (PFC) ac-dc converters is modeled and analyzed in this paper. A large-signal model is presented for the input impedance which overcomes the limitations of traditional piece-wise linearized models. The model is valid at frequencies ranging from the crossover frequency of the output voltage loop to half the switching frequency of the converter. Experimental results from a boost single-phase PFC converter are provided to validate the model. Input characteristics of typical boost PFC converter designs, such as input impedance dipping, leading phase of the input current, and responses to distorted lines are studied by using the model. A simple compensation technique to reduce the dipping in the input Impedance thereby improving converter performance and minimizing the potential for undesirable interactions with the input EMI filter is also presented. [141] R. Teichmann, S. Bernet, and M. Luscher, "State-of-the-art low voltage and high voltage igbts in soft switching operation," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 938. This paper presents switching and short circuit behavior of state-of-the-art low and high voltage IGBTs in soft switching operation. PT and NPT trench-gate IGBTs are compared with standard and optimized fast IGBTs in zero voltage and zero current switching operation. The soft switching characteristics of 1.2kV, 3.3kV, and 4.5kV IGBTs are presented. A test set-up that constitutes an auxiliary resonant commutated pole switching cell is used to characterize the devices. [142] S. T. Ting and H. Nianci, "A novel zero-voltage and zero-current-switching full-bridge pwm converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1088. A novel zero-voltage and zero-current-Switching (ZVSZCS) full-bridge PWM converter is presented. There is no additional winding or additional active switches or lossy components in the proposed converter to achieve ZVSZCS conditions, moreover, the ZVSZCS conditions are achieved without added control, so the converter is efficient and cost effective. The ZVSZCS conditions of the primary are achieved by changing the traditional configuration of ZVS-full-bridge PWM converter: a simple auxiliary circuit is added in the secondary and the center tap of the transformer's secondary is linked to the auxiliary circuit. The secondary rectifier voltage of the converter is clamped to a relative low level, so additional clamp circuit for the secondary rectifier is not necessary. The operation of the proposed converter is analyzed. And the experimental results of a 1.2KW prototype prove the novel converter is successful. [143] L. M. Tolbert, J. Chiasson, K. McKenzie, and Z. Du, "Elimination of harmonies in a multilevel converter with non equal dc sources," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 589. The problem of eliminating harmonics in a multilevel converter in which the separate DC sources vary is considered. That is, given a desired fundamental output voltage, the problem is to find the switching times (angles) that produce the fundamental while not generating specifically chosen harmonics. Assuming that the separate DC sources can be measured, a procedure is given to find all sets of switching angles for which the fundamental is produced while the 5<sup>th</sup> and 7<sup>th</sup> are eliminated. This is done by first converting the transcendental equations that specify the elimination of the harmonics into an equivalent set of polynomial equations. Then, using the mathematical theory of resultants, all solutions to this equivalent problem can be found. Experimental results are presented to validate the theory. [144] T. Tolle, T. Duerbaum, and R. Elferich, "De-embedding of reverse recovery losses in fast switching vrm applications," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 958. For the Synchronous Buck converter used in VRM applications, one major contributor to switching losses is reverse recovery. These losses however cannot directly be measured because capacitive current and several other phenomena superimpose the mere reverse recovery. The paper describes how calculate the capacitive part of the drain current and how to deembed the channel current out of the total drain current. This can show the size of Q<sub>rr</sub> and reveal effects such as gate bouncing and avalanche breakdown. [145] V. Tuomainen, "A passive clamp circuit for bifred converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 658. BIFRED is a well-known Single-Stage AC/DC converter. The converter integrates a power factor corrector stage and a dc-dc stage to a single switch converter. Due to this integration the leakage inductance of the transformer has a pronounced effect on the voltage stress of the switch. In this paper we propose a passive clamp circuit that clamps the voltage over the switch to a relatively low and predictable value. This allows for the use of a switching device of a lower voltage rating and, therefore, a device with a lower on-resistance and conduction losses. [146] D. M. Van de Sype, K. De Gusseme, A. P. Van den Bossche, and J. A. Melkebeek, "Duty-ratio feedforward for digitally controlled boost pfc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 396. When a 'classical' current control scheme is applied, the input current of a boost power factor correction (PFC) converter leads the input voltage, resulting in a nonunity fundamental displacement factor and in important zero-crossing distortion in applications with a high grid frequency (e.g. 400Hz power systems on commercial aircraft). To resolve this problem, a current-control scheme is proposed using duty-ratio feedforward. In this paper, the input impedance of the boost PFC converter for both the classical current-loop controller and the controller using duty-ratio feedforward are derived theoretically. A comparison reveals the advantages of the proposed control scheme: a low total-harmonic-distortion (THD) of the input current, a resistive input impedance, virtually no zero-crossing distortion and a fundamental displacement power factor close to unity. The theoretical results obtained are verified using an experimental setup of a digitally controlled boost PFC converter. [147] F. R. S. Vicenzi, L. C. Gomes de Freitas, E. P. Da Silva, E. A. A. Coelho, J. B. Vieira Jr, V. J. Farias, and L. C. De Freitas, "A new proposal of soft-commutated power oscillator that can be applied as an electronic ballast for fluorescent lamps," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1191. A new switched power oscillator with reduced conduction losses, zero voltage and zero current turning on, and zero voltage turning off is presented in this paper. The proposed topology consists on a Half-bridge converter associated to a self-oscillating LC series resonant circuit. This new power oscillator can be applied as an electronic ballast for fluorescent lamps as well as an auxiliary medium open loop power supply. Circuit description, a simplified design guide line, mathematical analysis and simulation results are presented in this paper. Experimental results from a 100 Watts, 150 Volts input voltage laboratory prototype switching at 13.5 kHz are included. [148] J. A. Vilela Jr, A. R. Vaz, V. J. Farias, L. C. De Freitas, E. A. A. Coelho, and J. B. Vieira Jr, "A high power factor electronic ballast with a single switch and single power stage," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1198. This paper presents a high power factor electronic ballast used to operate fluorescent lamps with a single power stage and single-switch. This topology has been obtained by combination of Buck-Boost converter and a new inverter topology with coupled inductors. The use of a single active switch allows a reduction in the number of components used in control and power circuits. The equations used in the proposed reactor design and also in the choice of the semiconductor devices have been presented. A prototype with switching frequency equal to 50kHz has been built to startup 40W fluorescent lamps. [149] H. Visairo, E. Rodriguez, P. Alou, and J. A. Cobos, "Multi-output half-bridge converter with single-winding self-driven synchronous rectification," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 341. This paper presents a multi-output Half-Bridge converter with Single Winding Self-Driven Synchronous Rectification (SWSDSR), which is a very suitable topology for high-current low-voltage applications with a wide input voltage range. Important benefits as high efficiency and multi-output capability are obtained. With the proposed converter it is possible to drive all Synchronous Rectifiers through the gate voltage waveforms obtained from only one additional winding. Design considerations and experimental results of a 25W laboratory prototype are included in the paper. [150] C.-M. Wang, "A novel single-stage full-bridge buck-boost inverter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 51. A novel single-stage full-bridge series-resonant buck-boost inverter (FB-SRBBI) is proposed in this paper. The proposed inverter only includes a full-bridge topology and a LC resonant tank without auxiliary switches. The output voltage of the proposed inverter can larger or lower than the DC input one, depending on the instantaneous duty-cycle. This property is not found in the classical voltage source inverter, which produces an AC output Instantaneous voltage always lower than the DC input voltage. The proposed inverter circuit topology provides the main switch for turn-on at ZCS by a resonant tank built before the output choke. The nonlinear control strategy is designed against the input dc perturbation and achieves well dynamic regulation. An average approach is employed to analyze the system. A design example of 500W DC/AC inverter is examined to assess the inverter performance and it provides high power efficiency above 90% under the rated power. [151] J. Wang and F. Z. Peng, "A novel configuration of unified power flow controller," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 919. This paper presents a novel configuration of Unified Power Flow Controller (UPFC). The proposed configuration has two inverters connected face-to-face on the ac side instead of connected back-to-back through a common DC link. The new configuration has the following advantages: 1) there is no active power exchange between the two inverters and both inverters only provide or absorb reactive power; 2) cascade multilevel inverters can be used in this configuration, thus eliminating the conventional magnetic interface - zigzag transformers, and greatly reducing power losses; 3) the total required VA rating of the inverters can be reduced greatly over a wide load conditions; and 4) The new configuration with modular cascade multilevel inverters and their redundancy has greater flexibility to system design and realization of higher reliability. [152] L. Wang, Y. Huang, Z. Zhang, and K. Tang, "Cascade multi-level converters with sample-time-staggered space vector modulation," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 268. A novel modulation strategy for cascade multi-level converters, Sample Time Staggered Space Vector Modulation, is put forward in this paper. The equivalent switching frequency is improved and the harmonic component is greatly decreased under this technique. The frequency and harmonic feature is analyzed by simulation. The experimental result is in accord with the analysis. [153] S. Wang, F. C. Lee, and W. G. Odendaal, "Power connector parameter analysis by 2d," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 751. Modern high-speed microprocessors require low impedances connectors with their power supplies. This paper presents a method to calculate two-dimensional inductances, capacitances and resistances. The connector parameters are modeled under transient conditions and the effects of pin shape and pin location on connector parameters are analyzed. Good agreement was obtained between computed results and finite element software simulations. Guidelines are also presented for reducing the impedances. [154] S. Wang, F. C. Lee, and W. G. Odendaal, "Improving the performance of boost pfc emi filters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 368. In order to design a high performance PFC EMI filter, many issues need to be considered beforehand. Some important issues including PFC noise source characteristics, its effects on EMI noise, impedance mismatch, and filter's parasitic parameters are discussed in this paper. Experiments are performed to verify the arguments. A filter is finally built to verify the analysis. [155] H. H. Weatherford and C. W. Brice, "Simulation of industrial ac drive system under fault conditions," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 457. An industrial motor drive suffers from periodic failures of the DC link aluminum electrolytic capacitor bank. Simulations pinpoint likely causes, including problems with the design of the balancing resistors. Stress on the capacitor can be produced by faults in the inverter and by open-conductor faults in the balancing resistors. [156] J. Wei and F. C. Lee, "A novel soft-switched, high-frequency, high-efficiency, high-current 12v voltage regulator - the phase-shift buck converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 724. This paper presents two novel soft-switched high-frequency high-efficiency, fast transient response 12V voltage regulator (VR) topologies - the phase-shift buck (PSB) and the matrix-transformer phase-shift buck (MTPSB) - for high current applications. They Improve efficiency at high switching frequencies and also feature very simple magnetic structures. For future high-frequency, high-current 12V VRs, PSB and MTPSB converters are the cost-effective solutions. Experimental results confirm the theoretical prediction. [157] S. Wei, B. Wu, F. Li, and C. Liu, "A general space vector pwm control algorithm for multilevel inverters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 562. To solve the problem of computational complexity in multilevel inverters due to the large number of space vectors and redundant switching states, a simple and general space vector PWM algorithm is proposed. Based on this algorithm, the location of the reference voltage vector can be easily determined and the calculation of dwell times becomes very simple. More importantly, the proposed algorithm is general and can be directly applied to the cascaded H-bridge inverter of any voltage levels. In addition, a new switching sequence, Large-Small Alternation (LSA), is proposed for the minimization of total harmonic distortion. To verify the algorithms, a 7-level cascaded H-bridge inverter drive system was constructed and experimental results are provided. [158] S. Wei, B. Wu, F. Li, and X. Sun, "Control method for cascaded h-bridge multilevel inverter with faulty power cells," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 261. To increase the fault tolerance for cascaded H-bridge multilevel inverters, a novel control algorithm is proposed for the Inverter operating under faulty conditions. The influence of various faults on space vectors is investigated and the maximum achievable output voltage of the inverter with faulty power cells is derived. Making use of the redundant switching states, the proposed algorithm is able to produce a three-phase balanced line-to-line voltage with minimum harmonic distortion for the Inverter with disabled power cells. In addition, the control algorithm is suitable for use in the cascaded H-bridge inverters of any voltage levels. Simulation and experimental results are provided for verification. [159] R. V. White, "Emerging on-board power architectures," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 799. In recent years, the feature size of silicon devices has decreased at a steady rate. Each step in feature size has required a reduction in operating voltage. As today's system designers seek to maximize performance, they use a wide variety of integrated circuits. The result is a system that requires many different supply voltages for various devices in the system. It is not unusual for a system today to require seven or eight different voltages and systems with twelve or more voltages are not uncommon. To meet this challenge, the traditional distributed power architecture has been extended to create the Intermediate Bus Architecture. This paper explores the Intermediate Bus Architecture and highlights areas of special concern to system and power system developers. [160] A. Wojtasik and B.-E. Skoglund, "Technical risk and economic factors in telecom on-board power design," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 786. This paper addresses the cost and risk factors involved in the selection of on-board power solutions in telecom systems. The solutions considered include standard off-the shelf DC/DC power modules and designs based on discrete components mounted directly on the board. The study Includes all major sources of risk and expense for the OEM - design, time to market, manufacturing and test, and field support. [161] D. E. Wood and J. T. DiBene Ii, "High performance, low impedance power interconnects," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 747. Power distribution Interconnects have become subject of stringent constraints on the electrical and mechanical performance as microprocessor speeds and their number of transistors keep rising. This increases the power/current draw dramatically both in magnitude and slew-rate. This paper describes a new power distribution Interconnect device that addresses these needs. [162] T. F. Wu, C. L. Shen, and H. S. Nei, "A 1φ3w grid-connection pv power inverter with apf based on nonlinear programming and fzpd algorithm," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 546. This paper presents design and implementation of a single-phase three-wire (1φ3W) grid-connection PV power inverter with active power filter which is based on nonlinear programming and fast-zero-phase detection (FZPD) algorithm. The proposed inverter system can not only transmit PV power but can compensate harmonic currents, supply reactive power, and balance power at source side even when the line voltages are highly distorted. Simulated and experimental results have verified the FZPD algorithm and demonstrated that when the voltage sources are highly distorted, the proposed inverter system can yield better power quality over that with zero-crossing detection. [163] W. Wu, W. Qiu, N. Pongratananukul, K. Rustom, T. Kasparis, and I. Batarseh, "Dsp-based multiple peak power tracking for expandable power system," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 525. A DSP-based improved maximum power point tracking (MPPT) approach for multiple solar array application is presented. It incorporates a "shared bus" current sharing method that can regulate many paralleled current mode DC/DC converters. The modular architecture eases the expansion of system power. The current sharing and MPPT performance of the proposed system is validated and evaluated by a 500-W prototype with two solar arrays. [164] X. Xie, G. Luo, D. Jiao, Z. Qian, and J. M. Zhang, "An improved self-driven synchronous rectification for a resonant reset forward converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 348. An improved self-driven synchronous rectification (SDSR) for a resonant reset forward converter is proposed in this paper. Three 9-18V input, 5V/5A output, 210kHz resonant forward prototype converters with the conventional SDSR method, the gate charge retention SDSR method and the proposed method are built up to compare their efficiencies. Experimental results prove that a relatively higher efficiency is achieved with this proposed SDSR method. [165] X. Xie, Q. Song, G. Yan, and W. Liu, "Matlab-based simulation of three-level pwm inverter-fed motor speed control system," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1105. The need for energy savings and introduction of new high power devices like IGCTs accelerate the broad use of medium and high voltage adjustable speed drives (ASD) in industrial and traction applications. As part of the mission to design a 6kV, 1600kVA three-level converter-based ASD, a simulation system is developed using MATLAB package for the purpose of validating the practical power electronic circuits and offering suggestions for controller design. In the paper, various aspects of the proposed simulation system are discussed, including the Simulink modeling of the power electronic circuit, control mechanism of the simulation and the friendly graphic user interface (GUI). Some key issues in improving simulation efficiency are also highlighted. For illustration, two control schemes, the conventional V/F control and the Direct Torque Control (DTC), are investigated. The starting process of the controlled motor system is simulated. Results demonstrate the effectiveness of the developed simulation system and also the superiority of DTC over open-loop V/F control in speed regulation and torque response. [166] Y. Xing, L. Huang, X. Cai, and S. Sun, "A combined front end dc/dc converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1095. Holdup time is a special requirement for front end DC/DC converters. It forces the converter to operate in a wide range for input voltage, which greatly degrades the converter's normal efficiency. In this paper a new front end DC/DC converter, a novel combination of an asymmetrical half bridge and a baby-boost with special control, is proposed. The baby-boost stands by under normal conditions and operates inherently only during the hold up time. As a result, the performances of high efficiency, power density and wide range of input voltage are all obtained. Topology and operation principles are presented with simulated and experimental results given in detail. [167] Y. Xiong, Y. Zhang, K. Wei, and Z. Zhang, "Carrier phase-shifted spwm based current-source multi-converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 89. Carrier Phase-shifted SPWM (CPS-SPWM) technique is applied to current-source multi-modular converter with output current harmonics minimization and without the use of high frequency modulation. Mathematical model of multi-modular CPS-SPWM technique is built and analyzed. Then digital current-source CPS-SPWM signal generating technique is developed. The proposition is verified by the experimental waveforms and the simulation results. [168] F. Xu, "An analytical framework for market research and forecasting in the power supply industry," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 187. The purpose of this paper is to propose a comprehensive analytical framework for market research and forecasting in the power supply industry. Within this analytical framework, there are three levels of analysis: macroeconomic conditions, business models, and technological developments, which correspond to a "macro-micro-macro" approach. Factors at each level of analysis affect market size, market growth and company market shares in different ways. [169] L. Yan and B. Lehman, "Isolated two-inductor boost converter with one magnetic core," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 879. This paper presents a new isolated two-inductor boost converter. All magnetic components are integrated into one magnetic core. The circuit has the two inductor windings Intrinsically coupled. The operation principle of the new circuit is presented. A prototype 100 W DC/DC boost converter has been built. Experimental and simulation results are both presented. [170] B. Yang, F. C. Lee, and M. Concannon, "Over current protection methods for llc resonant converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 605. LLC resonant converter was getting more and more attention in recent years because of its high efficiency, high frequency operation capability and simple structure. In this paper, the over current protection issue of LLC resonant converter is discussed. Three methods to provide over current protection function for LLC converter are proposed and investigated. They are: increase switching frequency control, variable frequency + PWM control, and diode clamping method. The pros and cons for each method were discussed. Tests were performed to verify the discussion. [171] G.-J. Yang, C.-Y. Du, Y.-P. Lu, and L. Sun, "Model of permanent magnet inductor type synchronous motor," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 69. The linear model and magnetic network model have been developed for the three-phase permanent magnet inductor synchronous motor (PMISM) with distinguishing structures. Deduced from the established magnet network model, self inductance and mutual inductance are functions of rotor position rather than constants. It indicates the salient pole effects shouldn't be neglected. At last, the dq mathematical model associated with the output torque equations has been developed for torque control. [172] L. Yang, F. C. Lee, and W. G. Odendaal, "Measurement-based characterization method for integrated power electronics modules," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 490. A measurement-based method for high frequency characterization of active integrated power electronics modules (IPEMs) is proposed. Parasitic inductances and capacitances inside the IPEM can all be extracted using this method without breaking the structure. The linearized model includes effects of the non-linear frequency dependencies of resistances and inductances, the structural capacitances and any ground planes. Extracted parameters are compared to those from commercial software and the results are in good agreement. A parallel resonance method is proposed for the characterization of common-mode capacitances. [173] K. Yao, K. Lee, M. Xu, and F. C. Lee, "Optimal design of the active droop control method for the transient response," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 718. Use of the Active droop control method is a popular way to achieve adaptive voltage position (AVP) for the voltage regulator (VR). This paper discusses the small-signal model of the active droop control method, which is shown to be a two-loop feedback control system. The compensator design Impacts both the current and voltage loops, making the design complicated. An optimal design method is proposed in order to achieve equal crossover frequencies for the two loops so that constant output impedance is realized in the VR. Simulation and experimental results prove the good VR transient response and high efficiency. [174] K. Yao, Y. Ren, J. Wei, M. Xu, and F. C. Lee, "A family of buck-type dc-dc converters with autotransformers," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 114. This paper Introduces a family of buck-type DC-DC converters with autotransformers, including forward, push-pull, half-bridge, and full-bridge topologies. Compared with an isolated transformer, the autotransformer has a simpler winding structure, and it only needs to transfer part of the input power, resulting in a smaller secondary winding current. Analysis shows that the autotransformer can also help to reduce the voltage stress and current ratings of power devices in the DC-DC converters. For some applications, a simple lossless passive clamp circuit can be implemented to solve the transformer leakage problems, and the gate drive is significantly improved with a simple self-adaptive dead-time-controlled bootstrap gate driver. Simulation and experimental results show that the proposed topologies are very suitable for high-frequency applications. [175] M. Ye, M. Xu, and F. C. Lee, "1 mhz multi-resonant push-pull 48 v vrm," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 413. For future high-end server and workstation applications, it will be impractical for voltage regulator modules (VRMs) to draw power from the 12 V output of the silver box because the voltage bus will be too low to deliver the increasing high levels of power. Therefore, distributed power systems (DPSs) with buses of 48 V will be more feasible solutions for future high-end computers. This paper presents a novel multi-resonant push-pull (MRPP) topology for 48 V VRMs, based on methods for reducing the conduction loss and eliminating the body diode conduction and reverse-recovery losses of the synchronous rectifier. Two 48 V-1.2 V 70 A prototypes are built, and their efficiency is 86% at 1 MHz. [176] S. Ye and Y.-F. Liu, "Emi filter design method for communication power sub-system," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 483. This paper Introduces an improved and simplified method to design EMI filters for switching power supplies (SPS), for both AC-to-DC and DC-to-DC. This method is based on using an engineer's way to measure the maximum and the minimum differential mode (DM) and common mode (CM) EMI noise impedance, and consider them in designing the EMI filters. Information of the topology and control method of the power supply is not needed. This method solves the limitations of the old EMI filter design methods, which are either too complicated to use, or based on ideal cases. The analyses and experimental results show that this method can guarantee that the required attenuation can be achieved, especially at low frequency. [177] J.-S. Yim, J.-H. Kim, S.-K. Sul, H.-J. Ahn, and D.-C. Han, "Sensorless position control of active magnetic bearings based on high frequency signal injection method," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 83. This paper proposes a novel method to estimate the position of suspended body that hovers due to the electromagnetic force. The position information of the suspended body can be extracted from the coil currents, which contain the high frequency components due to the injected high frequency voltage without any additional hardware. The control of coil currents and the position of suspended body is performed with the digital controller using DSP. The effectiveness of the position estimation and control strategy without displacement sensors has been verified by simulation and experimental results. [178] H. Yu, J. Lai, X. Huang, J. H. Zhao, J. Zhang, X. Hu, J. Carter, and L. Fursin, "A gate driver based soft-switching sic bipolar junction transistor," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 968. This paper presented a new soft-switching concept that the soft transition is achieved based on gate driver control. A new soft-switched IGBT and MOSFET Gated Transistor (SS-IMGT) base drive structure is proposed for high power SiC BJT. The proposed base scheme can proportionally drive SIC BJT into near-saturate region. In addition, the zero voltage turn-on for BJT can be adaptively achieved at all load current range with very simple control. The whole SS-IGMT structure could be regarded as an "improved" voltage driven device. The new structure has Inherent soft transition property with reduced stress and switching loss. The proposed gate driver based soft switching method is verified by experimental test with both Si and SiC BJT. SiC BJT demonstrate superior turn-off behavior compared to Si BJT. Further effort will be on utilizing the excess energy of resonant inductor to further reduce the conduction voltage drop across SiC BJT. [179] A. Zaghlol, W. Leonard, and R. Culham, "Characterization of swaged mixed metal heat sinks," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1037. The present experimental study investigates the thermal performance of four heatsink combinations based on the forced convection heat transfer mode. The four designs consist of an all Aluminum, all Copper, Copper baseplate/Aluminum fin and Aluminum baseplate/Copper fin heatsink. Each heat sink combination was tested in pairs of heatsinks placed within a vertical wind tunnel of Plexiglas walls such that the fins were positioned vertically and parallel to the airflow inside the tunnel. A block heater providing 800 watts and covering 60% of the baseplate was placed in between two identical heat sinks. Experiments were performed for an approach velocity ranging from 2 m/s to 8 m/s. The average rise in temperature of eight measured locations was used to calculate the thermal resistance. The all Copper heatsink provided the lowest thermal resistance while the all Aluminum heatsink returned the highest value. The experiments show that there is marginal improvement of 3% in the performance of the Copper-Base/Aluminum-Fin heatsink due to the higher conductivity of the Copper base. The experiments show that the thermal performance can be improved by up to 14% by increasing the thermal conductivity of the fin material, as in the case of the Aluminum-Base/Copper-Fin heatsink. [180] W. Zhang, G. Feng, Y.-F. Liu, and B. Wu, "A new predictive control strategy for power factor correction," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 403. A new predictive control strategy for PFC is presented. Its basic idea is that all of the duty cycles required to achieve unity power factor in a half line period are generated in advance by using a predictive algorithm. Based on the average output voltage in the previous half line period, the duty cycles in the current half line period can be calculated by the predictive algorithm, which is derived from the differential equations of Boost topology. An optimization process is incorporated with the predictive algorithm to fine tune the parameter of model for the purpose of further reducing the harmonic current. Benefited from the proposed digital control strategy, the switching frequency of the PFC does not directly depend on the processing speed of the DSP. Simulation results show that the proposed strategy works well and unity power factor can be achieved with wide input voltage and load current variation range. [181] W. Zhang, D. Xu, and C.-H. Lee, "Design and performance of digital ballast for hps lamps," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1205. This paper presents the design and performance of digital ballast for HPS lamps, which employs a 8-bit microprocessor to improve the starting technique and operate HPS lamp at rated power over the service life. The system offers the capability of dimming lamp from 100% to 50% power by changing the switching frequency of the inverter. It is also found that, under present experimental conditions, the lamp is free acoustic frequency and resistive operated at high frequency. The 3.2kV ignition pulse is sufficient for a cold 250W HPS lamp startup. Experimental measurements have shown the feasibility of the digital ballast with the proposed control strategies. [182] C. Zhao, D. Xu, and H. Fan, "A pwm plus phase-shift control bidirectional dc-dc converter," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 641. A PWM plus phase-shift control bidirectional DC-DC converter is proposed. In this converter, PWM control and phase-shift control are combined to reduce current stress and conducting loss, and to expand ZVS range. The operation principle and analysis of the converter are explained, and ZVS condition is derived. A prototype of PWM plus phase-shift bidirectional DC-DC converter is built to verify analysis. [183] Q. Zhao and F. C. Lee, "High performance coupled-inductor dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 109. Many emerging applications call for high-efficiency, high-step-up DC-DC converters. Basic DC-DC topologies encounter extreme duty ratio and severe rectifier reverse-recovery problems. Cascade DC-DC converters can meet the requirements with the drawbacks of extra complexity and higher cost. Coupled-inductor DC-DC converters can provide high step-up voltage gain without the penalty of extreme duty ratio, but the stress and the loss related to the leakage energy are severe concerns. In this paper, high performance coupled-inductor DC-DC converters which can effectively handle the leakage energy are proposed. Not only the extreme duty ratios are eliminated but also the rectifier reverse-recovery problem is alleviated. Theoretical analysis and experimental results verify the proposed solutions. [184] S. Zheng and D. Czarkowski, "High-voltage high-power resonant converter for electrostatic precipitator," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1100. A phase-controlled series-parallel resonant converter for electrostatic precipitators is described. Compared with the traditional line-frequency power supplies, the converter is smaller in size, higher in efficiency, and provides a faster transient response. The converter is digitally controlled and the possibility of spark control using a DSP algorithm is explored. Operating behavior of the power supply with the nonlinear precipitator load is experimented and investigated. [185] H. Zhu, B. Arnet, L. Haines, E. Shaffer, and J.-S. Lai, "Grid synchronization control without ac voltage sensors," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 172. To improve the cost and reliability of utility-tied PWM inverter, this paper investigates an ac voltage sensorless grid synchronization control, either in grid-parallel inverter mode or in boost PFC rectifier mode. Based on d-q coordinate, the sensorless technique utilizes an ac line voltage estimator and an angle-searching algorithm. By commanding a positive or negative d-axis current, the fast current loop regulator controls a bidirectional power flow. The method can detect when the grid is gone, as a possible built-in anti-islanding function. Experiments verified the validity of the proposed method. [186] J. Y. Zhu and B. Lehman, "Control loop design for two-stage dc-dc converters with low voltage/high current output," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 859. This paper presents a general analysis framework for control loop design of two-stage converters. The results yield a thorough explanation of various loop design approaches. A three-loop method to extend the system bandwidth is proposed. The new control design algorithm is applied to a 48 V/3.3 V two-stage converter. Experiments verify the effectiveness of the control loop design approach. [187] Y. Zhu and B. Lehman, "Three-level switching cell for low voltage/high-current dc-dc converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 121. New three-level converter topologies are proposed for application of low voltage/high current output dc-dc conversions. The proposed converters operate with small current ripple. Therefore, filter inductor value can be reduced, leading to fast transient response. First, the operation principles of these converters are described. Then inductor design for the converters and control implementation is presented. Computer simulations and experiments verify the basic operation of the new converters. [188] P. Zumel, O. Garcia, J. A. Cobos, and J. Uceda, "Magnetic integration for interleaved converters," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 1143. In this paper several techniques for integration of magnetic components in interleaved converters are analyzed. Magnetic components define the way the energy is transformed. Several opposite approaches can be considered: from decoupled integrated inductors to tightly coupled inductors. The integration of inductors in the same core for multiphase converters is especially analyzed from the point of view of size, losses and coupling. [189] I. Zverev, "Switching frequency related trade off's in a hard switching ccm pfc boost convert," in Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2003, pp. 671. The combination of silicon carbide Schottky diodes (thinQ! [trademark]) and power MOSFET CoolMOS [trademark] C3 sets a new efficiency benchmark in hard switching circuits like CCM PFC. Much higher switching frequencies become feasible. Trade off between switching frequency, size of the system and power losses in all components will be discussed.