Dissertation Projects by variablepitch348

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									MSc (Power Engineering) – 2009/2010 (Semester 1)

Dissertation Projects
Updated: 8 Aug 2009

Project No: 09/10-S1-D 1. AIM1 Supervisor A/P Ali lftekhar Maswood Co-supervisor Title Reactive Power Compensation in a DFIG in Wind Turbine The doubly-fed induction generators (DFIF) have found promonance in wind turbine system to generate electric power. This is because of its ability to compensate reactive power efficiently and economically. The aim of this project work will be to study the Summary DFIG, develop a model and also the model of the AC-DC-AC converter necessary to control the rotor winding reactive power. One also needs to develop a suitable controller for the converter to draw maximum electrical power from DFIG irrespective of the wind speed. The DFIG can be considered for isolated loads or for grid connection.

Project No: 09/10-S1-D 2. AIM2 Supervisor A/P Ali lftekhar Maswood Co-supervisor Title Developing a Hybrid Solar/Fuel Cell Converter Among Alternative energy sources, solar and Fuel Cell energies are excellent in isolated low to mid power applications. These two energy sources also complement each other. Considering the high cost of electrical energy available from these sources, it is Summary worthwhile to economise in its capital cost. An integrated solar/fuel cell converter can be very attractive in such a case. The project will concentrate in doing just that, which will start from literature search, conduct comparative study with isolated systems, Develop models and finally propose some viable topologies.

Project No: 09/10-S1-D 3. AIM3 Supervisor A/P Ali lftekhar Maswood Co-Supervisor Title A Hybrid Solar Array/AC Grid Power System with Near Sinusoidal Input Current This project deals with a specific case of a Solar Array/AC Grid hybrid system for domestic/industrial utilization. At nominal load condition, most of the power comes from the solar panels which operate at MPPT mode. The grid is merely utilized to provide additional power, i.e. under additional loads, motor starting currents and likes. Such an approach is gentle on the solar panels and does not require batteries or ultra-capacitors. Summary A prominent feature of the proposed system is the near unity PF and sinusoidal current which is drawn from the utility GRID, conforming the IEEE 519 standard. This is accomplished by using bidirectional switches across the front end rectifier and with an intelligent current control. The proposed system is capable of handling a variety of loads, including DC and AC motors for pumps and lifts, household lights and other appliances.

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Project No: 09/10-S1-D 4. AIM4 Supervisor A/P Ali lftekhar Maswood Co-supervisor Title Optimal Fuel Cell Power Extraction Renewable energy sources are now finding importance because of high energy cost and of environmental concerns. Fuel cells have found special applications in hybrid electric vehicles. Among different varieties, the proton exchange membrane (PEM) type of fuel cell is found to be more suitable in such applications. However, in order to extract PEM cell internal power efficiently, one needs a suitable DC-DC converter. A properly Summary designed converter will not only boost the output voltage, but will also maintain its magnitude. The aim of this work will be to look into such matters. This includes finding the V/I characteristic of the PEM cell, designing the converter controller to match this V/I characteristic for optimal power extraction.

Project No: 09/10-S1-D 5. CSS1 Supervisor Prof Choi San Shing Co-Supervisor Title Impacts of Hydro-Generators on Low-Frequency Oscillations Recently, sustained low-frequency oscillations have been reported on transmission networks associated with large hydro-generation schemes. It is suspected that the cause of the problem could be due to the design of turbine-governor control systems in the hydro-generators. Counter measure includes some operational adjustments (such as increase transmission voltage) to the power systems. These are not satisfactory for the Summary long-term. Some preliminary studies using selected cases of the hydro systems have indicated that the turbine control systems could cause instability. Thus the initial stage of this project is to confirm the study conclusions are valid. An analysis will also be carried out to support the study results. Counter measures, such as the addition of stabilizers into the turbinegovernor control systems, are to be explored.

Project No: 09/10-S1-D 6. CSS2 Supervisor Prof Choi San Shing Co-supervisor Determination of Energy Storage Capacity Requirement for a Hybrid Renewable Title Power Generation System The aim of this project is to determine the optimal storage capacity so as to extract the maximum economic benefit from a hybrid renewable energy generating station. It is well-known power outputs from renewable sources such as from wind, photovoltaic, or tidal are unsteady. This is because the energy production from these sources depends on climatic/weather conditions. In recent study, several schemes involving the use of battery energy storage systems (BESS) have been examined for wind generators. The BESS act like energy buffers such Summary that the output power from the wind farm-BESS can be regulated to suit the operational requirements of the network. The purpose is for load leveling purpose. In this project, it is proposed to use statistical means to quantify the energy/power contents of a hybrid renewable power generation station where wind, solar, tidal and other sources are included. The project is to devise a method to determine the capacity of the energy storage system so as to maximize the economic benefit that can be obtained from the energy captured from the hybrid sources. 2

Project No: 09/10-S1-D 7. CSS3 Supervisor Prof Choi San Shing Co-supervisor Title Hybrid Energy Storage Systems The project is to examine the application of hybrid energy storage system for renewable power generating station. The storage system is to act as power buffer to stabilize power outputs from renewable sources such as wind, solar or tidal. In recent study, schemes involving the use of battery energy storage systems (BESS) have been examined for wind generators. The BESS energy buffer is controlled in such a way that the output power from the wind farm-BESS can be regulated to suit operational requirements of the network. Summary The energy/power contents of the renewable power station output can be characterized via statistical means. The project is to devise a scheme to segregate the power input from the renewable source(s) into bands according to the speed of the power variations, such that the hybrid energy storage medium can be applied to maximize energy harness for electricity production, as well as to provide adequate energy support to achieve power quality enhancement. The hybrid storage system could include the use of BESS, flywheel and/or super-capacitor.

Project No: 09/10-S1-D 8. CSS4 Supervisor Prof Choi San Shing Co-supervisor Title Super-Capacitor for Power Quality Enhancement The project investigates the use of super-capacitor as a medium of energy storage system in renewable power generating plant. Power outputs from renewable sources such as from wind, solar or tidal are unsteady and hence, their impacts on network supply quality can be of major concern. In recent study, several schemes involving the use of battery energy storage systems (BESS) have been examined for wind generators. The BESS act as energy buffers such Summary that the output power from the wind farm-BESS can be regulated to suit operational requirements of the network. The purpose is to achieve power dispatchability. In this project, it is proposed to examine the possible role of super-capacitor in the renewable power plant. The aim is to investigate how effective the capacitor can be to improve power quality so that economical design can be obtained. The study will involve the modeling of the super-capacitor, and the determination of the capacitor capacity to achieve set performance target.

Project No: 09/10-S1-D 9. CFH1 Supervisor A/P Choo Fook Hoong Co-Supervisor Title Single-Phase Multi-Lamp Energy Savers The objective of this project is to design and fabricate an energy saving device for fluorescent lamp lighting system using switching technique. System is expected to handle up to 100 lamps with unity power factor using two switching devices (IGBTs) Summary switching at a few kilohertz synchronised with the supply frequency. Combined pulsewidth modulation (PWM) and pulse-position modulation (PPM) will be used where the device drive signals and control generated from a microcontroller.

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Project No: 09/10-S1-D 10. CFH2 Supervisor A/P Choo Fook Hoong Co-supervisor Title Magnetic Levitation for Vertical-Axis Cyclone Wind Turbine (VACWT) Modern wind turbines have been successfully implemented across the globe to tap onto one of nature’s natural energy resources. These turbines are of the three-bladed design driving a gear-box through its horizontal axial and are mounted on top of the windturbine tower several meters high. Unlike the horizontal axis turbine generator, the vertical axis generator allows the shaft to be anchored onto a magnetic-levitated system allowing friction free rotation. This helps to resolve some of the problems and efficiency of the horizontal axis system in Summary addition to the various advantages of having most of the major components sitting on the base instead being at the top of the tower. In this project, magnetic levitation will be studied and applied here to keep the vertical rotating shaft suspended in a magnetic field. A number of designs will be studied, modelled and simulated with the view to fabricate one of them to be incorporated with the Vertical-Axis Cyclone Wind Turbine system (VACWT). This project has the potential to mitigate carbon emission through the use of alternative energy in a large scale.

Project No: 09/10-S1-D 11. CFH3 Supervisor A/P Choo Fook Hoong Co-supervisor Title Effects of Harmonic Compensators and Power Converters on Power System In an environment where there are many electrical drives using a combination of dc converters and ac inverters, harmonic compensators are used to ensure harmonics propagated in the vicinity and up-stream are within the governing standards. Harmonic compensators can be of the passive and active types. Passive compensators are of the LC type while dynamic compensators use power electronics that are dynamically controlled to compensate harmonics generated by the drives. Power for these drives and converters are fed from one or more transformers. As the load of these drives changes dynamically with time, it is impossible to have the whole system tuned correctly all the time. It has Summary been reported that the power system can experience oscillation under certain conditions. The aim of this project is to study such a system by creating a model of the system using Matlab/Simulink. The modelling will involve the power system together with the drives. Based on the model, various operating scenarios will be carried out to study the effects of loading, under and over-compensation of harmonics, and input sources on the impedance characteristic and stability of the system. This project will allow students to experience a real system and the kind of problems that the industrial world faces today as more and more high technology power electronic equipment are connected to the power system.

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Project No: 09/10-S1-D 12. CFH4 Supervisor A/P Choo Fook Hoong Co-supervisor Title Vertical-axis Cyclone Wind-Turbine Generator (VACWT) Modern wind turbines have been successfully implemented across the globe to tap onto one of nature’s natural energy resources. These turbines are of the three-bladed design driving a gear-box through its horizontal axial and are mounted on top of the windturbine tower several meters high. Unlike the horizontal axis turbine generator, the vertical axis generator allows the shaft to be anchored onto a magnetic-levitated system allowing friction free rotation. This helps to resolve some of the problems and efficiency of the horizontal axis system. Moreover a vertical-axis turbine can exploit the roof effects of building making it ideally Summary suited to homes in addition to open-space deployment. The project will study the different designs of VACWT to maximise the energy transfer from wind to electrical energy. Focus will be on the cyclone blade design and the effect on its operation and energy transfer. Modelling and simulation may be conducted prior to prototyping. Wind tunnel testing will be conducted to gather further data on the design to verify its effectiveness. This project has the potential to mitigate carbon emission through the use of alternative energy in a large scale.

Project No: 09/10-S1-D 13. CFH5 Supervisor A/P Choo Fook Hoong Co-Supervisor Title Generator Design for Vertical-axis Cyclone Wind Turbine System (VACWT) Modern wind turbines have been successfully implemented across the globe to tap onto one of nature’s natural energy resources. These turbines are of the three-bladed design driving a gear-box through its horizontal axial and are mounted on top of the windturbine tower several meters high. Unlike the horizontal axis turbine generator, the vertical axis generator allows the shaft to be anchored onto a magnetic-levitated system allowing friction free rotation. This helps to resolve some of the problems and efficiency of the horizontal axis system. Summary Because of this design, numerous generator designs is now possible to be mounted to the turbine. One possibility is the use of its bigger diameter for the stator coil for a multi-phase generator. In this project, we propose to study and design a permanent magnet synchronous generator to exploit the advantage of the vertical-axis turbine. This project has the potential to mitigate carbon emission through the use of alternative energy in a large scale.

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Project No: 09/10-S1-D 14. DMV1 Supervisor A/P Don Mahinda Vilathgamuwa Co-Supervisor A/P Loh Poh Chiang, Andrew Title Damping of Harmonics in Power Distribution Systems using Hybrid Active Filters Harmonic propagation along power distribution lines due to resonance characteristics of line inductances and power capacitors can be a serious power quality problem. There is a certain degree of understanding of this problem and solutions proposed are in terms of installation of shunt and series active filters in strategic locations. The student is Summary required to model a typical distribution system and propose suitable control algorithms to dampen harmonic propagation. The student may use Matlab/Simulink for this purpose. Subsequently, the proposed control algorithms can be tested using a laboratory built hardware prototype.

Project No: 09/10-S1-D 15. DMV2 Supervisor A/P Don Mahinda Vilathgamuwa Co-Supervisor A/P Loh Poh Chiang, Andrew Title Virtual-flux Based Control of Distributed Generation System Virtual-flux based control of power converters has a few good properties in terms of its simplicity and good dynamic properties. In this project the student is required to apply such a control system to distributed generation system. The student may modify the existing control schemes to suit an environment with zero Summary sequence components and may explore possible modulation strategies. Matlab/Simulink can be used to model a distributed generation system equipped with such a control technique. Subsequently, the proposed control system can be tested using a laboratory built hardware prototype.

Project No: 09/10-S1-D 16. DMV3 Supervisor A/P Don Mahinda Vilathgamuwa Co-Supervisor Title Modelling and Control of Boost-buck Rectifier Boost-type PWM voltage source rectifiers have gained popularity because they allow the output voltage to be controlled over a wider range. However newly proposed boost-buck Summary converter would allow buck capability with minimal number of switches. This project aims at modeling such boost-buck rectifiers and developing suitable control strategies.

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Project No: 09/10-S1-D 17. DMV4 Supervisor A/P Don Mahinda Vilathgamuwa Co-Supervisor Title Analysis of Microgrid Operation and Control A new paradigm called microgrids is a cluster of loads and microsources operating under an unified controller within a certain local area. The microsources are low cost, low voltage, highly reliable and have power electronic interfaces and reduced emission. These micro sources can be micro-turbines, photovoltaic panels or fuel cells. With correctly designed power electronics and controllers microgrids should be able to fulfill customers' as well as utilities' requirements. This can be described in terms of Summary increase in reliability, power quality and efficiency. Therefore special attention must be paid to the development of controllers for those micro sources that can switch from grid connection to island operation without causing problems for critical loads. Moreover special protection schemes must be incorporated as classical relay system may not be able to protect sensitive electronic converters in the microgrid. The developed power conditioners and their controllers must be tested in the laboratory by means of a hardware-prototype.

Project No: 09/10-S1-D 18. DMV5 Supervisor A/P Don Mahinda Vilathgamuwa Co-supervisor Title STATCOMs for Wind Power Generation Applications Recently, renewable wind energy is enjoying a rapid growth globally to become an important green electricity source to replace polluting and exhausting fossil fuel. However, with wind being an uncontrollable resource and the nature of distributed wind induction generators, integrating a large-scale wind-farm into a power system poses challenges, particularly in a weak power system. In the project, the impact of STATCOM Summary to facilitate the integration of a large wind farm into a weak power system is studied. First, an actual weak power system with two nearby large wind farms will be examined. Based on some available data, the power quality issues are investigated and a centralized STATCOM is proposed to solve them, particularly the short-term (seconds to minutes) voltage fluctuations. Subsequently, a model of the system, wind farm and STATCOM for steady-state and dynamic impact study needs to be studied.

Project No: 09/10-S1-D 19. GHB1 Supervisor A/P Gooi Hoay Beng Co-supervisor Title State Estimators for Microgrids A traditional State Estimator used at Power System Control Center (PSCC) normally does not measure voltage phase angles. Rather they are derived from power balance equations and KVL equations of voltage magnitude measurements, real and reactive power flow measurements, circuit breaker statuses, tap positions, etc via minimization of Summary the error square function. Assuming that phase measurement units (PMUs) are available, this project is to focus on using phase angles supplied by PMUs and solve the entire voltage values of the microgrid network. Both digital and analog bad data will be examined and dealt with in the proposed solution algorithm. The results of the proposed solution algorithm will be compared to those of the traditional SE.

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Project No: 09/10-S1-D 20. GHB2 Supervisor A/P Gooi Hoay Beng Co-supervisor Title Forecasting Loads for Microgrids Unlike traditional customers, microgrid customers may have their own energy sources such as co-generators, micro-turbines, solar panels and wind generators. Hence they may choose to generator their own electricity when the price of electricity from their suppliers increases. A microgrid as a single entity needs to predict the total system load within the microgrid. This is important as microgrid needs to schedule the generators under its Summary control to maximize its profit or some other optimization criteria. This project is to examine how the system load can be forecasted based on weather conditions, day types, operation hours and customer bid prices. The student is to focus on the design of the forecasting algorithm. Sample test data from typical renewable energy sources should be used in testing the proposed load forecasting software.

Project No: 09/10-S1-D 21. LKG1 Supervisor Prof Lalit Kumar Goel Co-Supervisor Title Literature Survey of Power System Reliability Assessment in Deregulated Power Markets In a conventional power system, generation, transmission, and distribution facilities are generally owned by a single company. Customers have little or no choice in regard to their purchases. In a deregulated power system, generation utilities are physically connected to different system buses, and the generation and transmission facilities can belong to different owners. These generation utilities (Gencos) provide customers with electric energy through the transmission system. A generation utility has to make consistent planning, operating, bid and investment decisions based on load demand, load growth, customer reliability expectation, customer price demand, the price that other Gencos offer, available transmission and the associated tariffs. A distribution system (Discos) and its customers can therefore select one or more generation companies as their service providers. A customer potentially has a wide range of choices regarding power suppliers based on the price and reliability. A Disco should select the best power generation and corresponding transmission system based on generation adequacy, Summary transmission reliability and the price offered. The deregulated environment creates more uncertainty factors, which will affect system operation and reliability. These uncertainty factors have to be considered in power system planning, operation and trading processes. This project will involve a detailed literature survey on power system reliability evaluation techniques vis-à-vis the deregulation aspects. Monte Carlo simulation methods, analytical methods, and other developed methods will be covered under the survey. The objective is to list all technical papers that have been published over the last 15 years (since 1990) to determine the reliability of customer load points in the deregulated power market structure. The impacts of load forecasting, transmission losses, generator maintenance scheduling, and price of electricity on the customer supply point reliability at the generation system level, the combined generation and transmission system (composite system) level, and the distribution system level will also be included in the listing. The final list is expected to be an excellent source of reliability-based literature in deregulated electric power systems.

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Project No: 09/10-S1-D 22. LFL1 Supervisor A/P Luo Fang Lin Co-Supervisor Title Energy Factor and Mathematical Modelling of Power DC/DC Converters Energy storage in power DC/DC converters has been paid attention long time ago. Unfortunately, there is no clear concept to describe the phenomena and reveal the relationship between the stored energy and mathematical modelling of power DC/DC converters. A new concept - Energy Factor (EF) has been theoretically defined, and the relations between EF and the characteristics of power DC/DC converters have been well researched. EF is a new concept in power electronics and conversion technology, which Summary differs from the traditional concepts such as power factor (PF), power transfer efficiency (η), total harmonic distortion (THD) and ripple factor (RF). EF and the subsequential EFV and EFVD can illustrate the system stability, reference response and interference recovery. This investigation is very helpful for system design and DC/DC converters characteristics foreseeing. Various DC/DC converters, e.g. Buck converter, SEPIC and Super-Lift Luo-Converter as the samples are analysed in this project to demonstrate the applications of the new parameters of EF, EFV (and EFVD), PE, SE, VE (and VED).

Project No: 09/10-S1-D 23. LFL2 Supervisor A/P Luo Fang Lin Co-Supervisor Title Sub-Envelope Modulation Method to Reduce THD of AC/AC Matrix Converters AC/AC matrix converter is an array of power semiconductor switches that connects directly a three-phase AC source to another three-phase load. It can convert an AC power source with certain voltage and frequency to another AC load with variable voltage and variable frequency directly without DC link and bulk energy storage component. Classical modulation methods such as Venturini method and space vector modulation (SVM) method using AC-network maximum-envelop modulation, implement matrix conversion successfully. However, in the mean time they cause very high total harmonic distortion (THD). Since matrix converters directly link loads to sources, high THD Summary heavily pollutes power system, and damages other equipment’s work. It restricts to apply matrix converters in industrial applications. This paper presents a novel approach: SubEnvelope Modulation (SEM) method to reduce THD of matrix converters effectively. The approach is extended to an improved version of matrix converters and the THD can be reduced further. The algorithm of the SEM method is described in detail here. The method regarding current commutation is also proposed. Simulation and experiment results are also presented to verify the feasibility of the SEM approach. The results will be very helpful for industry applications.

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Project No: 09/10-S1-D 24. LFL3 Supervisor A/P Luo Fang Ling Co-supervisor Title Research on DC-Modulated AC/AC Converters AC/AC converters are popular equipment widely applied in various industrial applications. Traditional voltage regulated AC/AC converters have disadvantages such as high total harmonic distortion (THD), low power factor (PF) and poor power transfer efficiency (η). A new idea of the DC-Modulated AC/AC Converters is advanced by using DC/DC conversion technique to improve the power factor correction (PFC). Then achieve the advantages of very low THD, high PF and high efficiency, even more to reach the unity power factor (UPF). This method not only save the energy, but largely Summary reduce the power supply pollution as well. This project combines the best strategies of both conversion technologies: DC/DC conversion and AC/AC conversion skills. The new method opens a broad way for AC.AC converters. It will be widely used in industrial applications. The student to take this dissertation has to do both software and hardware work. He/she is encouraged to construct hardware circuit, and then carry out the experimental tests. The software simulation and experimental test results are need to verify the effectiveness of the new method.

Project No: 09/10-S1-D 25. LFL4 Supervisor A/P Luo Fang Lin Co-supervisor Title Super-Lift DC/DC Converters The purpose is to build a new DC/DC converter with high voltage transfer gain. These converters can convert a positive source voltage, e. g. 10 ~ 20 V into hundreds and thousands volts or even higher. Traditional DC/DC converters such as Boost Converter can only increase the output voltage by a few times. Cascaded converters Summary can only increase that to tens times. The new type converters – Super-Lift converters have the voltage transfer gains in stage by stage with geometrical series, i.e. can easily increase the output voltage by tens to hundreds times. This technique is very useful for the industrial applications which require high output voltage.

Project No: 09/10-S1-D 26. LFL5 Supervisor A/P Luo Fang Lin Co-supervisor Title Four-Quadrant Operation ZCS DC/DC Converters Soft-switching technique is effective method to reduce the power losses in power DC/DC converters. Zero-current-switching (ZCS) is one of the most popular Softswitching techniques. Single quadrant operation (Quadrant I operation) has been well discussed in the literature. However, some industrial applications request multiple Summary quadrant performance, which is not well investigated. Based on the ZCS Quadrant I operation, other quadrants such as ZCS Quadrants II, III and IV operations will be investigated in this project. The student gas to study the theoretical knowledge and calculation formulae. The simulation and experimental results will offer evidences to verify all theory and calculations derived.

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Project No: 09/10-S1-D 27. LFL6 Supervisor A/P Luo Fang Lin Co-supervisor Title Four-Quadrant Operation ZVS DC/DC Converters Soft-switching technique is effective method to reduce the power losses in power DC/DC converters. Zero-voltage-switching (ZVS) is one of the most popular Soft-switching techniques. Single quadrant operation (Quadrant I operation) has been well discussed in the literature. However, some industrial applications request multiple quadrant Summary performance, which is not well investigated. Based on the ZVS Quadrant I operation, other quadrants such as ZVS Quadrants II, III and IV operations will be investigated in this project. The student gas to study the theoretical knowledge and calculation formulae. The simulation and experimental results will offer evidences to verify all theory and calculations derived.

Project No: 09/10-S1-D 28. LPC1 Supervisor A/P Loh Poh Chiang, Andrew Co-supervisor Title DSP / FPGA Controller Development The project plans to explore the implementation of time delay (repetitive), resonant and predictive controllers for converter control. The preferred hardware platform should ideally be a combination of digital signal processor (DSP) and field programmable gate Summary array (FPGA) or erasable programmable logic device (EPLD). The project is expected to involve C programming for controlling the DSP and logic code structuring for controlling the FPGA or EPLD.

Project No: 09/10-S1-D 29. LPC2 Supervisor A/P Loh Poh Chiang, Andrew Co-Supervisor Title Optimally Controlled Current Source Converter for Grid-Interfacing Current source converter (CSC) is well-recognized as the topology suitable for mediumvoltage energy conversion including grid-interfacing. To exploit the full functionalities of a CSC, this project proposes the development of an appropriate control algorithm for controlling CSC with fast dynamic response and minimal harmonic distortion. Particularly, students selecting this project will be required to: (a) Design and model an appropriately controlled CSC in Matlab/Simulink simulation Summary platform. (b) Implement a hardware prototype in the laboratory for experimental verification of the designed control algorithm. Students choosing this project will be guided on the development of software algorithms for controlling a physical hardware system, which would be helpful for the students’ future engineering careers.

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Project No: 09/10-S1-D 30. LPC3 Supervisor A/P Loh Poh Chiang, Andrew Co-Supervisor Dr Shen Weixiang Title Hybrid Battery Charging Methodologies Different types of batteries can be used for supporting critical loads from power interruption. Charging of these different batteries efficiently in an optimized Summary configuration can be challenging. This project is therefore proposed to address this concern with hopefully an efficient overall system eventually designed to support the critical operation of a water purification plant to be built at a test site in Changi.

Project No: 09/10-S1-D 31. MHH1 Supervisor A/P Mohammed Hamidul Haque Co-supervisor Estimation of Energy Efficient Induction Motor Parameters from Manufacturer Title Data The standard equivalent circuit (single-cage rotor model) of an induction motor cannot predict the starting characteristics of modern energy efficient motors. Such a motor needs to be modelled with a double-cage rotor. Unfortunately, the manufacturers do not provide the equivalent circuit parameters but supply some catalogue data. Translation of these data into equivalent circuit parameters is a nontrivial task. The objective of this project is estimate the parameters of a double-cage induction motor model from manufacturer catalogue data, such as rated output power, speed, current, Summary power factor and efficiency at rated power, breakdown torque, starting torque, and starting current. First a set of non-linear equations in terms of motor parameters is to be established using the manufacturer data. The motor parameters are to be determined from the above equations through an optimization technique or an iterative process. Finally, the correctness of the estimated parameters will be checked by evaluating some external characteristics of the motors and comparing them with the corresponding actual values supplied by the manufacturer.

Project No: 09/10-S1-D 32. MHH2 Supervisor A/P Mohammed Hamidul Haque Co-supervisor Title Analysis of an Induction Generator Connected to an Infinite Bus The increasing concern for the environment, especially the greenhouse effect, has motivated the world towards rationalizing the use of fossil fuels and exploring the use of non-conventional energy sources to meet the energy demand. Wind, bio-gas, hydro, solar, etc. are considered as non-conventional energy sources. Generation of electricity from above sources has received much attention in recent years. Induction generators are very commonly used to generate electricity from some non-conventional energy sources, such as wind and hydro. There are two modes of operation of an induction generator: Summary stand-alone (self-excited) and grid connected. The objective of this project is to study, investigate and analyze the operation of an induction generator connected to a large grid system (which can be considered as an infinite bus) through a long transmission line. The operating conditions of the generator are to be modelled mathematically. The student is expected to simulate the developed model using MATLAB software to obtain various characteristics of the generator. The effects of excitation capacitor and line reactance on the terminal voltage and active power transfer capability of the generator are also to be investigated.

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Project No: 09/10-S1-D 33. GS1 Supervisor A/P Govinda Bol Shrestha Co-Supervisor Title Analysis of Bidding Regulations and Practices by Gencos in Competitive Markets The market clearing regulations have evolved in differently in different power markets. These regulations influence and shape the bidding practices adopted by the Gencos, which may include strategies to maximize profits within the regulations. Summary Under this project, the student may undertake a theoretical or empirical analysis of bidding regulations and/or practices of Gencos in general or in a specific power market such as Singapore power market. The historical data available for different power markets can be utilized in this project.

Project No: 09/10-S1-D 34. GS2 Supervisor A/P Govinda Bol Shrestha Co-Supervisor Title Feasibility of Distributed PV Generation Although PV generation is very environment friendly and desirable from many respects, it is still expensive compared to traditional sources of energy. It has been investigated and used as ‘Distributed Energy’ source in niche markets. This project is to investigate the relevant factors which will make PV Distributed Generation feasible in the present day power systems.

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Project No: 09/10-S1-D 35. SPL1 Supervisor A/P So Ping Lam Co-Supervisor Design and Development of a Test Bed to Investigate Conducted and Radiated Emissions from Broadband PLC Networks Power line communications (PLC) is an economical alternative to communicate over existing power lines. But before it can be commericialized, emissions from PLC networks have to be below regulatory limits. Main electromagnetic interference (EMI) emission issues which have to be resolved are conducted and radiated emissions from PLC networks. In order to lower EMI emissions from PLC networks it is critical to first Summary understand the phenomenon of conducted and radiated emissions. And to get insight, a test bed which will facilitate reliable measurement of both conducted and radiated emissions is essential. In this project, a test bed to measure conducted and radiated emissions from PLC networks will be developed. Student who is interested in Electromagnetic Inferference and Compatibility (EMI/EMC) field is encouraged to apply. Title

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Project No: 09/10-S1-D 36. SPL2 Supervisor A/P So Ping Lam Co-Supervisor Title Design of a Microgrid for Intelligent Energy Distribution Microgrid is an integrated energy system consisting of a low-voltage distribution network with distributed energy resources (such as fuel cells, solar photovoltaics and wind turbines), power electronic converters, storage devices and loads, operated either connected to the grid or islanded. A technical challenge of microgrid is the operation and Summary control of distributed energy resources within a microgrid. The aim of this project is to design a microgrid to integrate the distributed energy resources for intelligent control and management of energy distribution within the microgrid. Furthermore, control strategies for a microgrid to operate either in grid-connected mode or in islanded mode will be explored. The use of Matlab for simulation studies will be required.

Project No: 09/10-S1-D 37. SPL3 Supervisor A/P So Ping Lam Co-Supervisor Title Modeling and Control of Combined Cycle Plants The modeling of combined cycle plants and their controllers are crucial to the understanding of their dynamic characteristics and to evaluate their impacts on power systems. It is important to assess the control system behaviours and the overall plant performance subject to system disturbances. The significance and aim of this project is to model the dynamics of industrial combined cycle plants in parallel and isolating Summary conditions, so that a unified platform will be provided for the comparison of different control strategies via both mathematical analysis and computer simulations. Through this model, rigorous methods for the design of advanced controllers for these combined cycle plants can also be developed. These controllers will provide improved dynamic performance and system robustness to industrial and utility applications such as disturbance rejection and load variation.

Project No: 09/10-S1-D 38. WP1 Supervisor A/P Wang Peng Co-Supervisor Prof Lalit Kumar Goel Title Nodal Price and Nodal Reliability Analysis of Restructured Power Systems Power systems in the world are experiencing the restructuring. The restructuring has resulted in the changes in power system planning and operation. Centralized reliability management has been replaced by demand side reliability. Uniform electricity price is Summary being replaced by different price mechanism such as spot price and bilateral contract price. This project is to evaluate power system real time nodal price and nodal reliability and nodal market power when considering transmission network limitations.

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Project No: 09/10-S1-D 39. WP2 Supervisor A/P Wang Peng Co-Supervisor Title Intelligent Trading/Metering/Billing System (ITMBS)-I: Metering The ITMBS consists of bidirectional Digital Energy Meters (DEMs), Digital Water Meters (DWMs), Digital Ggas Meters (DGMs), Power Line Comunication Network (PLCN), Computer Database, Billing Software (CDBS) and Computer Network. The system can automacically meter, read and bill the electricity, water and gas consumption of each household in a City. The system allows electricity users to select their electircity suppliers through their meters to take into consideration of power market requirements and to check Summary monthly bill from user meters. It can also meter electricity sold to the power grid to incooperate the new regulation which allows family’s renewable power (such as fuel cell, solar and wind) to connect to Power Grid, to develop the network structure of the system using power line, wireless or cable network and reduce the error of data transfer between meters and computers using suitable new network protocal. This project focuses on metering part.

Project No: 09/10-S1-D 40. WP3 Supervisor A/P Wang Peng Co-Supervisor Title Intelligent Trading/Metering/Billing System (ITMBS)-II: Network The ITMBS consists of bidirectional Digital Energy Meters (DEMs), Digital Water Meters (DWMs), Digital Gas Meters (DGMs), Power Line Comunication Network (PLCN), Computer Database, Billing Software (CDBS) and Computer Network. The system can automacically meter, read and bill the electricity, water and gas consumption of each household in a City. The system has trading function which allow electricity users to select their electircity suppliers through their meters to take into consideration of power market Summary requirements and to check monthly bill from user meters. It can also meter electricity sold to the power grid to incooperate the new regulation which allows family’s renewable power (such as fuel cell, solar and wind) to connect to Power Grid, to develop the network structure of the system using power line, wireless or cable network and reduce the error of data transfer between meters and computers using suitable new network protocols. This project focuses on network and the related ptotocols.

Project No: 09/10-S1-D 41. WP4 Supervisor A/P Wang Peng Co-Supervisor A/P Loh Poh Chiang, Andrew Title Stand-Alone Home Electricity Supply System (SHESS) using Solar Energy Solar energy is a very important source to replace the conventional sources such as coal and gas because it is free of pollution. In the future, electricity produced by renewable sources will replace that from conventional energy sources. Summary The objectives of the project is to develop a standard design procedure for determining capacity of solar panels and batteries and developing the corresponding DC/AC inverter, DC/DC inverter, and supply circuit layouts (switch, protection, etc.).

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Project No: 09/10-S1-D 42. WP5 Supervisor A/P Wang Peng Co-Supervisor A/P Loh Poh Chiang, Andrew Development of Grid-Tie Home Electricity Supply System (GHESS) using Solar Title Energy Solar energy is a very important source to replace the conventional sources such as coal and gas because it is free of pollution. In the future, renewable sources will replace conventional energy sources to produce electricity. More and more families will install their own electricity supply system. However, the electricity produced by solar panels depends on weather condition. During the cloudy days home electricity may be supplied by conventional power grid. During the sunny days, the extra electricity from the family Summary owned solar panels may sell its power to grid. The objective of this project is to develop a generalized procedure to design and build a solar/electricity conversion system for a family to supply its own electricity and to sell it to the power grid based on a particular capacity requirement, which include • A DC/AC inverter to convert DC supply from photovoltaic cells (solar panels) into AC (50Hz, 220 V) for a home supply • A control circuit to connect the solar/electricity system to local distribution system Project No: 09/10-S1-D 43. WP6 Supervisor A/P Wang Peng Co-Supervisor A/P Loh Poh Chiang, Andrew Development of Battery Charger for PV Systems (The part of S$10m project awarded Title to Water and Energy Lab by Singapore National Research Foundation) In standalone PV systems, the output of solar array is used to charge batteries. Due to the variation of weather conditions, the uncertain voltage of a solar PV charger must be conditioned to safely charge batteries and protect the batteries from overcharging. It also has the capability of temperature compensation of the battery charging algorithm with a thermistor that can be put on the battery. Since the solar PV is expensive, the power consumption of the solar PV charger should be very low and can work in the sleeping mode Summary during night time. The objective of this project is to develop battery charger for PV systems based on microcontroller with low power consumptions and battery protection functions. The pulse width modulation (PWM) method will be adopted to implement three-stage charging: constant current charge, variable current charge, and float charge. In this project, student will review existing charging algorithms for PV chargers, identify their problems and develop the PV charger suitable for the particular application. Project No: 09/10-S1-D 44. WP7 Supervisor A/P Wang Peng Co-Supervisor A/P Loh Poh Chiang, Andrew Development of the Photovoltaic System for DC Motor (The part of S$10m project Title awarded to Water and Energy Lab by Singapore National Research Foundation) Singapore government has identified water and environment related technologies as the prioritized technologies to be developed. The research in the use of solar energy to purify the water is to take these two technologies into account. In this research, solar photovoltaic (PV) has been used to drive a DC motor to pump water in a water purification plant. Summary The objective of this project is to develop solar water pump systems. The student can start to survey the efficiencies of different kinds of DC motor pump with the power rating around 100W and flow rate about 50 liter/hour and identify the most efficient one. The control of this DC motor pump driven by solar array will be investigated and its corresponding hardware will be implemented. 16

Project No: 09/10-S1-D 45. WP8 Supervisor A/P Wang Peng Co-Supervisor Wind Speed and Solar Irradiation Simulator for Microgrid Operation (The part of S$10m project awarded to Water and Energy Lab by Singapore National Research Foundation) Electricity produced by renewable energy sources such as wind and solar has experienced a tremendous growth in recent years. A microgrid is a mini power network with fossil fuel and renewable source-driven small generators to supply a group of users. The accurate wind speed and solar irradiation modelling is a key issue for the reliable operation of a microgrid. However wind and solar irradiation is under the great uncertainty due to the random nature of weather. Therefore it is necessary to develop the models to simulate wind speed and solar Summary irradiation. There are many methods which can be used to forecast the fluctuations of wind and solar energy production for microgrid operation for example regression and time-series methods. The objective of this project is to apply the above techniques to model and analyze the fluctuation of wind and solar energy production. Matlab is utilized as a tool to develop a software simulator for wind speed and solar irradiation modelling. Title

Project No: 09/10-S1-D 46. WP9 Supervisor A/P Wang Peng Co-Supervisor Maintenance Management for Distributed Wind Systems considering Power Quality and Reliability Aspects In the past 30 years, the size of wind turbines and the size of wind power plants have experienced large growth, which is caused by enhanced public awareness of the environment to reduce greenhouse gas emissions associated with conventional energy generation. However the development of large wind turbines and offshore farms has surpassed the infrastructure for which it was designed. The lack of standards, regulations and maintenance has proven to be an increasing threat to the reliability and power quality of the system. The issue is even more serious for offshore farms, where service is difficult and expensive. The industry has incentive to make maintenance management more efficient, which requires more accurate power quality and reliability assessment techniques for distributed wind systems. In this project, we focus on maintenance management for distributed wind systems considering power quality and reliability aspects. Summary Condition monitoring system (CMS) has been used for better wind turbine maintenance management and increased reliability. CMS continuously monitors the performance of wind turbine parts, e.g., generator, the gearbox and main shaft, which can help to determine the optimal time for specific maintenance. The combination of CMS and reliability and power quality analysis can be the major part of reliability cantered maintenance (RCM) of wind turbines. The aim of RCM is to relate preventive maintenance to total maintenance cost, system reliability and power quality in our studies. Further a life cycle cost (LCC) analysis, which calculate the total cost for the wind turbine during its lifetime will be carried out. The LCC is used to compare different alternative maintenance strategies. In this project, we are interested in analyzing the possibilities and benefits of RCM and CMS in a wind farm with the same and different types of wind turbines to increase system reliability and power quality. Title

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Project No: 09/10-S1-D 47. WP10 Supervisor A/P Wang Peng Co-Supervisor Title Control and Management of Microgrids considering Renewable Energy Resources The environmental and economic benefits of the microgrid are primarily determined by the envisioned controller capabilities and the management strategies. Because of the type and depth of penetration of renewable energy resource (RER) units, load characteristics and power quality constraints, the required control and management strategies can be significantly and even conceptually different from those of the conventional power systems: steady-state and dynamic characteristics of RER units coupled with electronics devices are Summary different with those of the conventional turbine generator units; a large portion of electricity supply within the microgrid can be from “non-controllable” RER units like wind-turbine and PV panel; energy storage plays a key role in control and operation of a microgrid. In this project, the control and management strategies of microgrids are studied, which are focused on the following two topics: 1. Voltage and frequency control and/or active/reactive power control for the RER units. 2. Power dispatch management of RER units for optimizing electricity output.

Project No: 09/10-S1-D 48. WYY1 Supervisor Prof Wang Youyi Co-supervisor Title Control of PEM Fuel Cells Proton exchange membrane (PEM) fuel cells convert the chemical energy of hydrogen and oxygen directly into electricity. A PEM fuel cell has many advantages such as fast starting at room temperature, no electrolyte leaking, long running time, high power rate and high energy rate. This project is aimed at development of controller design approaches for a PEM fuel cell. In this project the students will be required to do: Summary 1. Study the functions of a PEM fuel cell; 2. Set up models of PEM fuel cells; 3. Design control schemes to improve the performance; 4. Simulation. The project requires the students who have interests in control design and fuel cells.

Project No: 09/10-S1-D 49. WYY2 Supervisor Prof Wang Youyi Co-supervisor Title Power System Transient Stability Enhancement Power systems are complex nonlinear dynamic systems. Improving the stability of a power system under small and large disturbances is one of the most important problems in power system control. This project will concentrate on design of advanced controllers for power Summary system stability enhancement. Different operating conditions in a multi-machine power system will be considered. The system performance will be evaluated by computer simulation. The students require knowledge on power system and computer simulation.

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Project No: 09/10-S1-D 50. WYY3 Supervisor Prof Wang Youyi Co-supervisor A/P Cai Wenjian Title Design of Advanced Control System for a Solar Ejector Refrigeration System Solar ejector refrigeration system is a system combined an ejector refrigeration cycle and a solar collector. The ejector refrigeration system utilizing the solar energy offer several advantages: 1) by using the renewable free heat energies can improve the efficiency of performances and alleviate the environment problems, particularly by reduction of CO2 emission from combustion of fossil fuels; 2) natural substances such as water can be utilized as working fluids, which do not cause ozone depletion; and 3) it is more reliable Summary since there is no moving parts. This major objective of this project is aimed at control design approaches for solar ejector refrigeration system. In this project, the students will be required to do: 1. Study and understand the functions of solar ejector refrigeration systems; 2. Set up models of solar ejector refrigeration systems; 3. Design advanced control scheme to improve system performance; 4. Evaluate the system performance by computer simulations and experimental tests.

Project No: 09/10-S1-D 51. WYY4 Supervisor Prof Wang Youyi Co-supervisor A/P Cai Wenjian Title Advanced Controller Design for Wind Turbine Systems This project is aimed at application of advanced controller design approaches to wind turbine control systems. In this project, the students will be required to do: 1. Study and understand the functions of wind turbine systems; Summary 2. Set up models of wind turbine systems; 3. Design advanced control schemes to improve system performance; 4. Evaluate the system performance by computer simulations and experimental tests

Project No: 09/10-S1-D 52. WYY5 Supervisor Prof Wang Youyi Co-supervisor Prof Xie Lihua Title Controller Design of Linear Servo Motor Systems This project is aimed at development of controller design approaches for linear servo motor systems. In this project the students will be required to do: 1. Study the functions of linear servo motors 2. Set up models of linear servo motors Summary 3. Design control scheme to provide the motion control. 4. Evaluate the performance of the proposed controller by simulation. The project requires knowledge on fundamental understanding of a motor, motion control and control system. The project is a part of the research project.

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Project No: 09/10-S1-D 53. ZDM1 Supervisor Asst/P Zhang Daming Co-Supervisor Title Design of High Frequency Transformers for Power Electronic Circuits Miniaturization of power electronic devices is an ultimate pursuit of circuit designers. To make these devices as compact as possible, increasing operating frequency is a plausible choice. With the increased operating frequency, the put-through power handled by magnetic cores becomes larger with even smaller sizes. The highest operating frequency Summary for magnetic cores used in power electronic circuit can be up to 2MHz. With so high an operating frequency, many factors need to be considered in the design of a transformer or inductor. In this research, the undertaker will be able to know what these influential factors are in the design and how to incorporate all these factors in the procedure of designing an inductor and a transformer. Project No: 09/10-S1-D 54. ZDM2 Supervisor Asst/P Zhang Daming Co-Supervisor Title EMI/EMC Issues in Power Electronic circuits The operating frequency of switched-mode power electronic circuits can be as high as 1MHz. With such a high operating frequency, the electromagnetic interference posed by it to its ambient devices may need to be concerned. Furthermore the radiation by the high Summary frequency pulse can make the device fail in the test according to EMC/EMI standards, such as IEC standards. In this project, the researcher will calculate the radiation by a designed power electronic circuit operating at high-frequency and in switched mode and measure its near-field and far-field radiative pollution to its ambient. Project No: 09/10-S1-D 55. ZDM3 Supervisor Asst/P Zhang Daming Co-Supervisor Application of Parabolic Reflector to Collect Solar Energy and Convert it to Electricity In this project, the procedure to design parabolic reflector will be developed. Application of using Stirling engine and solar panel to convert concentrated solar energy to electricity Summary will be studied. Efficiency between the design system and normal solar panel system will be compared. Title Project No: 09/10-S1-D 56. ZDM4 Supervisor Asst/P Zhang Daming Co-Supervisor Issues on the Integration of Renewable Energy with existing Power Distribution Networks With the public awareness that current power consumption based on fossil and coal is not sustainable, more and more efforts have been in place to gain as much energy as possible from renewable energy sources. Integration of renewable energy with existing power Summary distribution systems is a worthy research topic. This proposed research studies the issues on the integration of renewable energy with existing power distribution network. Issues such as harmonic reduction, fault current limitation, protection system design and synchronization incurred by the integration will be studied. Title

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