"Customer Voltage Regulation"
Powertech Labs Inc. • 12388-88th Ave., Surrey, B.C. Canada • (604) 590-7500 POWERTECH LABS INC. Final Report Potential Benefits of Customer Voltage Regulation PROJECT 14418-23 REPORT 14418-03-REP1 Prepared for: BC Hydro Distribution KEYWORDS: Voltage Regulation; Power Quality; Energy Saving; Distribution Prepared by: Reviewed by: J. Bruce Neilson, Ph.D., P.Eng. Vern Buchholz, P.Eng. Specialist Engineer Director Electrical Technologies Electrical Technologies Signature Signature Date Date This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 1 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. INTRODUCTION The objective of this project is to review and summarize the potential benefits of customer voltage control to help determine whether further research or pilot projects are warranted. There are a number of manufacturers who market equipment intended to regulate voltage at the customer meter or main panel. This has some obvious benefits for the customer, but it also provides benefits to the utility, so consideration should be given to investing utility resources in this area. There is a wide range of possible mechanisms of support: simply providing information to customers, endorsing products, subsidizing installation programs, funding R&D programs, or directly purchasing and installing such equipment on either a pilot or full scale basis. This review is directed only at residential and commercial applications. This project is a first review to provide a preliminary assessment of the benefits associated with this technology. It is not a comprehensive study, but simply an initial assessment to determine whether further investigation is warranted. On the user’s part, the main benefits are reduced energy cost and improved power quality. In some cases these may be sufficient to justify the cost, but there will almost certainly be marginal cases where utility assistance will tip the balance to cost-effectiveness. On the utility’s part, there are savings in peak power demand and total energy consumption. Widespread use of the technology among many customers on a problem feeder would reduce the requirement for strict voltage control on that feeder, which could allow the utility to defer or eliminate some distribution system costs. Widespread adoption could also have an impact, probably an adverse one, on system stability, since it would affect the linearity of load with voltage. Finally, the technology will have an impact on power quality, both for users and non-users, which has cost implications for the utility since there are costs, both economic and non-economic, associated with power quality complaints. The report outlines the results of the literature survey that was done on the subject, and provides a breakdown of the estimated costs or benefits related to each of the above issues. LITERATURE SURVEY A literature survey was carried out to look for relevant publications, and the abstracts were reviewed to see if similar work has been done before. While several publications discussed the impact of voltage reduction on energy conservation, there were no publications that addressed the issue of customer voltage regulation. The abstracts identified in the search are listed in the Bibliography section. POWER AND ENERGY SAVINGS The most obvious benefit of voltage regulation, and the one that is most advertised by suppliers, is energy saving. This benefit must be analyzed with caution, keeping in mind that voltage regulation has an immediate impact on power, not energy. In some cases the two are directly related, but in others the connection is not so obvious. Some preliminary estimates are made here, but this is certainly a topic that could be examined further. There are several classes of load with different power-energy relationships. This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 2 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. 1. Incandescent lighting The power consumption is proportional to voltage squared and the duty cycle is unaffected by the voltage. It should be noted that as the voltage is reduced, the efficacy (light output per watt) drops substantially (a disadvantage), and the lamp lifetime increases, which is an advantage. Decreasing light levels due to reduced voltage might prompt customers to increase lamp wattage or add lighting, negating some power savings. Incandescent lighting is assumed to make up 75% of residential lighting and 25% of commercial lighting. 2. Other lighting This class includes fluorescent (linear or compact) and high intensity discharge lighting, which are assumed to make up 75% of commercial lighting, and 25% of residential. The power depends on the voltage, but the dependence is flatter than incandescent lighting. Some newer or premium ballasts are regulated, so that the power consumption is unaffected by voltage, but for this study we will assume the power is proportional to voltage, and the duty cycle is unaffected by voltage. 3. Electric heating This class includes space heaters, water heaters, and thermostatically controlled, electrically heated appliances such as ovens and clothes dryers. These loads consume peak power at a rate proportional to the voltage squared, but since they are controlled by thermostats the energy consumption is determined by the thermostat set point. The duty cycle increases to make up for the reduced power, and the energy consumption is unaffected by voltage. For example, if the voltage is reduced 5% the heat output of an oven element is reduced about 10%, but it will be on 10% longer in each thermostat cycle to maintain the oven temperature. When averaged over the cycle time, voltage regulation has negligible impact on the average power or total energy consumption of these appliances. 4. Refrigeration This category includes refrigerators, freezers and air conditioners. As with heaters, the average power and total energy consumption are determined by thermostats, and voltage control has little impact on the energy consumption. In this case, since the main load is a fully loaded compressor motor the peak power will also depend very little on the voltage, so we assume no impact on either peak power or energy with this type of load. One factor which we will not include is the defrost cycle of frost-free refrigerators. During this part of the cycle, a heater operates to melt frost, using additional power proportional to the square of the voltage. For this report the effect is neglected, but it may warrant further examination since it could have an impact on the dependence of load on voltage. 5. Motors Aside from refrigeration loads, the most significant motors in the residential sector would be furnace fan motors, and in the commercial sector HVAC motors, typically small single phase or three phase induction motors. The dependence between voltage and power with these motors is complicated. At idle or minimum load, as the voltage is reduced the core losses are reduced with the square of the voltage while other losses are unchanged, resulting in a dependence between linear and quadratic. Near full load there are two effects. If the motor load and speed (and thus the power output) are held constant, the motor current must increase, resulting in higher resistive losses in the windings, decreased efficiency, and a power consumption that increases with decreasing voltage. In practice, the slip will increase slightly and the motor speed will decrease with decreasing voltage. If the motor is driving a fan, the decrease in speed reduces the output power (with the cube of the speed) and the net This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 3 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. result may be that the decreased efficiency is more than offset by the decreased output power, leading to a slight drop in electrical power consumption. An efficiency model for a 1 hp fan motor gives the following power changes for a 10% voltage drop: -0.5% at 75% load, -1% at 50% load, and –16% at no load. Assuming that most motors are loaded to at least half rated load, we will use the 50% load value for this study, i.e. 1% power reduction for 10% voltage reduction. The duty cycle is assumed to be unaffected by air flow rate or voltage. 6. Electronic loads Electronic loads include items such as computers, consumer electronics, and motors powered from dc or electronic variable frequency drives. This component of the load can be expected to grow with time. These appliances typically have as a first stage a regulated power supply that compensates for changes in voltage. The power consumption and duty cycle will be unaffected by voltage. Each of these load types has a load response of the form P ∝ V a and E ∝ V b , where V is the voltage, P is the peak power consumption, and E is the total energy consumption over a longer time (hours or days). The coefficients a and b depend on the load type, and range from 0 (no change with voltage) to 2 (quadratic, which for small changes gives a power change twice the voltage change). When the components are combined in their typical proportions, the power and energy of the combined load have the same form, but the averaging produces average values of a and b that depend on the load composition. The power and energy coefficients for each type are illustrated in Figure 1, which shows the power and energy changes that will result from a 6% voltage reduction for each load type. Percent load at 94% voltage 100% 95% 90% pk power 85% avg energy 80% He Re El In Ot M ec ca ot he at fri or tro nd er ge rl s s es igh nic ra tio ce s tin n nt g Figure 1. Estimated response to voltage change of different load types This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 4 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. Residential, electric heat Residential, gas heat Commercial Incandescent Other lighting Heaters Refrigeration Motors Electronics Figure 2. Composition of typical residential and commercial loads Rough estimates of the load composition for different classes of customer are shown in Figure 2 and listed in Table 1 along with the resulting composite values of a and b. These are based on information obtained from BC Hydro Power Smart staff, with some interpretation by the author. Residential Residential Commercial a b Electric Gas Incandescent 7% 12% 10% 2 2 Other lighting 2% 4% 35% 1 1 Heating + ovens 70% 34% 7% 2 0 Refrigeration 10% 17% 20% 0 0 Motors 1% 8% 15% 0.1 0.1 Electronics 10% 25% 13% 0 0 Power coefficient a 1.57 0.98 0.69 Energy coefficient b 0.18 0.33 0.55 Energy Savings at 94% V 1.1% 2.0% 3.4% Table 1. Load composition and overall dependence on voltage. Percent load at 94% voltage 100% 95% peak power 90% avg energy 85% 80% R C R es om es ga m el er ec s ci al Figure 3. Load response to voltage change for different customer classes. This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 5 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. The power coefficient a is of interest primarily for system stability analysis, as it represents the dependence of instantaneous power on voltage. Both the energy consumption and the 15 minute peak demand are averaged over a long enough interval that their response will be determined by the energy coefficient b. We can therefore boil this analysis down to a set of energy exponents for the three classes of customers considered: electrically heated residential, gas heated residential, and commercial. Using the formula E ∝ V b we can then calculate the effect of voltage regulation on energy consumption for the customer classes. The most obvious conclusion from Table 1 is that the dependence of load on voltage is much weaker than would be expected from a simplified analysis assuming a quadratic dependence. Especially for customers with electric space heating, voltage regulation will provide much less benefit than might be expected. According to Hydro policy, service entrance voltage under normal operating conditions should be between 110 and 125V, with extreme limits of 106 to 127V. If voltage regulators are adjusted to hold the voltage at the 110V level, customer voltage reductions ranging from 0 to 12% should be achieved. Assuming the voltages follow a symmetrical distribution, the average voltage reduction should be 6% during normal operating conditions, with resulting energy and peak demand reductions of 1.1% to 3.4% as shown in Table 1. From the customer point of view, this is not likely to be economic for typical residential customers. For an electrically heated residence, with an average electricity cost of $100/month, the savings will be only about $1/month, and for a gas heated residence with an average electricity cost of $60/month the savings should be about $2/month. For best case customers at the near end of the distribution line the savings might be twice the typical values. For commercial customers there is a better chance of economic viability, with higher monthly bills and higher percentage savings. A small commercial customer might be able to save $40-$80 per month on a $1000 electricity bill. From Hydro’s perspective, there is a small but real average energy saving of 1.1 to 3.4% of the regulated load that can be used in a cost-benefit analysis. The peak demand will be reduced by the same amount as the energy. Comparison with System Tests A study of load versus voltage dependence was done by BC Hydro in 1993 (“Load to Voltage Dependency Tests at BC Hydro”, Alf Dwyer, Ron E. Nielsen, Joerg Stangl, Nokhum S. Markushevich, IEEE Summer Meeting, San Francisco, July 1994, paper 94 SM 541-3 PWRS). This study was done on a substation serving a mixture of residential and commercial customers, with approximately half the residential customers using electric space heating. The results found an energy coefficient (in their terms, percent kWh per percent voltage reduction) of 0.6 in the spring rising to 0.77 in the summer. Assuming a load breakdown of 50% commercial, 25% gas residential, 25% electric residential, Table 1 predicts an annual average coefficient of 0.4, which is somewhat lower. At the time the measurements were taken, however, heating loads would be low in spring and negligible in summer. The measured energy coefficients should be significantly lower in mid-winter due to the increased heating load. This would bring the annual average (weighted toward winter due to the higher load) into reasonable agreement with the This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 6 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. estimates. They also measured the short term response in the 15 minutes following a voltage change, which is similar to the power coefficient defined above, and arrived at values of 1.0 and 1.1. Considering the uncertainties involved, the measured results provide a good reality check for the estimates in Table 1. OTHER COSTS AND BENEFITS Reduced Distribution System Cost Under some circumstances customer voltage regulation may be a cost-effective alternative to improving system voltage control. This is likely to be applicable primarily in cases where a small number of customers are affected by daily or seasonal variations in loading on a long line. When customer voltages begin to stray outside the accepted limits the normal practice would be to install fixed or switched capacitor banks to maintain acceptable voltage. The capacitor size and cost are determined by the total load and the line impedance. The cost of customer voltage regulation, on the other hand, is determined by the number and size of affected customers. In a case where the variable load is large and very few customers are affected, the use of customer voltage regulation is likely to be a good alternative. Whether the line upgrade is eliminated or deferred, the cost savings could justify direct purchase and installation of a number of customer voltage regulation units. In the event that the capacitors are later installed, the regulators could be removed and installed elsewhere as needed. System Stability Under normal circumstances, one of the factors that helps stabilize the system is the dependence of load on voltage. If the generating capacity is reduced by the loss of a generator or line, the voltage tends to drop, which reduces the connected load. Similarly, if the voltage on a distribution line drops, the natural load reduction helps compensate for the drop and reduce the impact. The widespread installation of customer voltage regulation on either a line or the system reduces this tendency, and could in principle reverse the feedback to the extent that the system becomes unstable. In a worst case scenario, if all customers on a line had regulators and a system event caused a momentary voltage reduction, the regulators would maintain constant power by increasing their current demand. Since system losses are largely current dependent, the load would actually increase, and the system voltage could eventually collapse or go into slow oscillation. In practice, it is unlikely that enough of the system would be on customer regulation to cause such problems, but if the technology is widely adopted within parts of the system, the impact on stability should be assessed. Power Quality Since current technology is relatively slow to respond, customer voltage regulation is unlikely to have much impact on most aspects of power quality. Transients would be largely unaffected, as would outages. Sags and surges of relatively long duration (seconds to minutes) might be corrected by these voltage regulators, with two consequences. Customers equipped with voltage regulators would see very little change, as the regulators would correct the voltage at their main panel. For other customers on the same line, however, the impact would be negative. If a 10% sag occurred on a line where half the customers had regulators, the regulated customers would draw10% more current to compensate for the reduced voltage, which would make the sag worse This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 7 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. for other customers. With normal system impedances this is unlikely to have a severe impact. Perhaps a more serious concern is the possibility of introducing frequent voltage changes that could result in light flicker. Depending on the step size and frequency, voltage regulators could introduce periodic voltage fluctuations that might cause flicker problems, especially if a situation occurs where different regulators interact with each other to cause ‘hunting’ or oscillation. CONCLUSIONS Customer voltage regulation at the service entrance may have some application in the BC Hydro system. It can provide energy savings, with the average ranging from about 1.1% for electrically heated residential customers to about 3.4% for commercial customers. The most economic applications would be for commercial customers with a high percentage of incandescent lighting and a higher than average line voltage. The absolute best case for a customer with a load consisting only of incandescent lighting load and a service entrance voltage of 125 V would provide an energy saving of about 22%. For a customer served at 125 V with a more typical 45% lighting load, all incandescent, the energy saving would be about 10%. Customer voltage regulation is unlikely to be cost-effective for residential customers, but may be cost-effective for some commercial applications. Another opportunity for application is in cases where a small number of customers are affected by distribution line voltage variations, where it could be considered as an alternative to installing distribution line voltage control. These estimates of energy savings are based on theoretical analysis of load characteristics and are in reasonable agreement with measured results from a BC Hydro load test. There are some possible side effects on system stability and power quality, but unless the technology is widely adopted or concentrated on individual distribution lines these side effects are unlikely to have a significant impact. RECOMMENDATIONS A cost-benefit analysis study should be done to estimate the cost of installation and determine whether some form of BC Hydro support is justified for commercial applications of customer voltage regulation or voltage reduction. A cost-benefit analysis should be done to determine whether customer voltage regulation could be a viable alternative to tap changers or switched capacitors. This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 8 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. BIBLIOGRAPHY Title: Integrating engineering and economic analysis for conservation voltage reduction Author: Fletcher, R.H.; Saeed, A. Author Affiliation: Snohomish County, Everett, WA, USA Source: 2002 IEEE Power Engineering Society Summer Meeting (Cat. No.02CH37376) Part vol.2 p. 725-30 vol.2 Publisher: IEEE , Piscataway, NJ, USA Publication Date: 2002 Conference Date: 21-25 July 2002 Conference Location: Chicago, IL, USA Abstract: This paper presents a new process, which combines and automates engineering and economic analysis of distribution systems to determine feasibility of conservation voltage reduction (CVR) system efficiency projects. Distribution system improvements are evaluated with the use of a new engineering analyses tools which use annual feeder load profiles; customer load characteristics; topological data provided by GIS, capacitors, and regulating equipment and controls. The results of these analyses provide an estimate of annual kWh savings and economic evaluation for each proposed system improvement. This new engineering tool includes an 8760- hour load flow simulation of distribution system operation including customer load characteristic, voltage regulating equipment; and line drop compensation and switched capacitor control modeling. Performance and economic analyses of proposed system improvements are calculated and reported. Distribution system voltage can be designed as low as possible within acceptable limits. Project feasibility comparisons can be made using economic and performance indices. ( 21 Refs) Title: California voltage cuts saved 2.9 billion kWh in '77: PUC Source: Electr. Light Power (Boston) (United States) v 56:3. Coden: ELLPA Publication Date: Mar 1978 p 6 Abstract: The California Public Utilities Commission claims a year-old program to lower voltage has saved 2.9 billion kilowatt hours (or four million barrels of oil) and can increase that saving to 3.5 billion kWh by 1985. There was little capital investment by the utilities or awareness by the consumers. Substation voltage regulators were recalibrated so that voltages range between 120 and 114 instead of the usual 126 and 114. Adjustments to each circuit were based on a utility's criteria rather than on system-wide reductions. Besides saving money, the voltage cuts have increased the quality and length of service of electrical equipment without jeopardizing performance. Voltages had been lowered before during drought periods and for testing, when it was learned that voltage drops below 114 led to customer complaints. Title: Voltage regulation algorithm for a bi-phase distribution system feeding residential customers using a Beta p.d.f. load model Author: Herman, R.; Maritz, J.S. Author Affiliation: Dept. of Electr. & Electron. Eng., Stellenbosch Univ., South Africa Source: Electric Power Systems Research vol.43, no.2 p. 77-80 Publisher: Elsevier , Publication Date: Nov. 1997 This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 9 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. Country of Publication: Switzerland Abstract: This paper gives an analysis of the voltage regulation in a phase-anti-phase distribution network feeding residential customers. Grouped customer load currents are modeled using a Beta probability density function. The approach is complementary to the analysis that has been performed on conventional three-phase networks. The centre-tapped distribution topology promises to be an economic alternative in rural situations. A voltage regulation calculation algorithm is developed for the secondary circuit using the statistical moments of the load model. ( 3 Refs) Title: Innovative volt/VAr management provides payback Author: Dixon, Mark Source: Proceedings of the IEEE Power Engineering Society Transmission and Distribution Conference Atlanta, GA, United States. Conference Date: 2001/10/28 v 1 2001. p 461-468 (IEEE cat n 01CH37294) Publication Year: 2001 Abstract: Switched pole-top capacitor bank applications and their controls used to offset the varying VAr requirements on a daily basis were discussed. An auto adaptive volt/VAr management system enabling interaction between the pole-top capacitor bank controls and voltage regulation controls on the load tap changer transformer or tap change line regulator in the distribution system was described. The system was found to be capable of improving voltage, VAr and power factor profiles and power delivery to the end customer. (Edited abstract) Title: Voltage stability studies with PSS/E Author: Anon Source: Doktorsavhandlingar vid Chalmers Tekniska Hogskola, n 1397 1998. p A-1-A-26 Publication Year: 1998 Abstract: A study of simulations of voltage stability phenomena using the PSS/E program (Power System Simulator) is presented. The objective is to explain how the interaction of different components, such as on-load tap changers, field and armature current limiters and dynamic loads, can endanger the voltage stability of a system. Special attention is given to the user-written models that have been implemented in PSS/E. A computer model has been designed for a voltage regulator combined with field and armature current limiters. This combination is used for nuclear power plant generators in Sweden. Two different models for an on-load tap changer control unit commonly used have also been implemented in the program. The dynamic load model with load recovery is based on field measurements. Furthermore, some problems in using simulation tools are discussed, as well as the importance of parameter determination for some of the models implemented. The simulations highlight the importance of the generator current limiter and its interaction with the on-load tap changer and the type of load model chosen. (Author abstract) 16 Refs. Title: Advanced voltage regulation method of power distribution systems interconnected with dispersed storage and generation systems (revised) Authors: Choi, Joon-Ho ; Kim, Jae-Chul Source: IEEE Transactions on Power Delivery v. 16 no2 (Apr. 2001) p. 329-34 Abstract: A multiple line-drop compensation voltage regulation method for power distribution systems, interconnected with dispersed storage and generation (DSG) systems, is discussed. The This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 10 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. method determines the tap positions of under-load tap changer transformers to maintain customer voltage within permissible limits. Case studies indicate that the method can be applied effectively to practical power distribution systems having DSGs and/or severely unbalanced load diversity on different feeders. Title: New switching regulator's unique compensation scheme assures design simplicity Author Scolio, J. Author Affiliation: Nat. Semicond. Corp., Santa Clara, CA, USA Source: Official Proceedings of the Sixteenth International PCI '88 Conference, 3-6 Oct. 1988, Dearborn, MI, USA p. 101-11 Publisher: Intertec Commun , Ventura, CA, USA Publication Date: 1988 Country of Publication: USA 307 pp. ISBN: 0 931033 11 X Abstract: The author discusses the newly-designed LM1575 step-down switching voltage regulator, developed to supply the simplicity of use needed to coax the would-be user of a switching regulator away from linear regulators and their inherent inefficiency. The author looks at the design process (i.e. selection of inductor, capacitors), illustrating its relative ease. Key design notes are discussed. The fact is highlighted that the engineer will know all the key performance specifications of his circuit before he applies power to it. A discussion of a unique oscillator circuit developed to reduce the regulator's loop gain for the higher range of input voltages (and to eliminate the need for external compensation) is featured. (0 Refs) Title: Distribution capacitor automation that controls voltage and saves energy Author(s): Williams, B.R. Source: Fourth international symposium on distribution automation and demand side management (DA/DSM 94) Conference Title: International symposium on distribution, automation and demand-side management Conference Location: Orlando, FL (United States) Conference Date: 17-20 Jan 1994 Publisher: San Francisco, CA (United States) DSM 94, 3915 24th Street, Suite A, San Francisco, CA 94114 (United States) Publication Date: 1994 p 1-9 (747 p) Abstract: The Electric Distribution Business Line of Southern California Edison Company (SCE) has begun a program to improve the distribution system operations and electrical efficiency. The program, called the Distribution System Efficiency Enhancement Program (DSEEP), consists of five principal projects: Automated Switching, Circuit Lock-Out Alarming, Substation Monitoring and Control, Outage Management, and Distribution Capacitor Automation Project (DCAP). DCAP is the largest and most sophisticated of the projects being implemented. The project takes advantage of fine-tuning customer voltages for conservation voltage regulation (CVR) benefits as well as minimizes line losses by reducing unnecessary reactive power flow. DCAP can also help to increase transmission line and substation capacity by improving system power factor. The DCAP system takes advantage of the distributed processing capability of meters, capacitor controllers, radios, and substation processors. DCAP uses two-way packet radios and new electronic meters that read real-time customer voltages as well as energy consumption. The radios transmit customer meter voltage information and This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 11 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. capacitor status to substation processors, where a control algorithm runs to determine which capacitors should be turned on or off. The objective of DCAP is to reduce over-all net energy transfer from the substation to the customer and meet system VAR requirements. SCE has tested the system on 66 circuit capacitors (including 3 substation capacitors) on 18 circuits served from two substations. The positive results of the DCAP demonstrations has led to an aggressive roll- out plan for system-wide implementation of automating over 7600 switched capacitors by year- end 1995. Title: Design leadership for a distribution management system architecture Author(s): Green, T.A. Source: Fourth international symposium on distribution automation and demand side management (DA/DSM 94), Orlando, FL (United States) Conference Date: 17-20 Jan 1994 Publication Date: 1994 p 286-292 (747 p) Abstract: Distribution Automation (DA) as a concept has existed for more than a decade. However, it has only been recently through technological advancements and pilot projects by pioneering utilities that it has become an economic practicality. A number of leading utilities have contributed to the evolution of this technology. The performance goals to be achieved in implementing DA technology have been evolved through previous DA projects and have been established for ongoing projects. These goals establish a clear focus for defining implementation plans for DA technology and include the following: (1) Reduced Customer Outages; (2) Commercial Customer Retention Constant Voltage Regulation; (3) Capital Expenditure Reductions; and (4) Personnel Productivity. In the past decade, many Utilities have initiated a number of pilot projects, each designed to improve some aspect of the company's service to its customers. Each of these projects will impact the way the distribution system is operated and introduce new technology that must be mastered. Without a coordinated effort, these systems will be implemented in scattered locations using equipment, software, communication interfaces, and user interfaces that differ for each application. The distribution dispatchers would be required to interact with each of these ‘islands of automation’ separately, resulting in an increased level of complexity and an increase in the burden of their duties. A Distribution management System (DMS) architecture is needed to provide the infrastructure for coordinated implementation of DA technology. Using this broad company-wide model for automation, each pilot project can be viewed as part of a broader set of functions that will be supported by the DMS. Title: Mixed electric energy supply system including utility and non-utility generation Author(s): Toyoda, J.; Saitoh, H.; Sasaki, A. (Tohoku Univ., Sendai (Japan)) Source: New electricity 21: power industry technology and management strategies for the twenty-first century Corporate Source: Nuclear Energy Agency, 75 - Paris (France) Conference Title: International Energy Agency international conference on power industry technology and management strategies for the 21st century Conference Location: Tokyo (Japan) Conference Date: 12-14 May 1992 Publisher: Paris (France) Organisation for Economic Co-Operation and Development Publication Date: 1993 p 313-318 (922 p) Report Number(s): CONF-920551— ISBN: 92-64-14073-5 This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 12 of 13 Customer Voltage Regulation - Project 14418-23 Powertech Labs Inc. Abstract: The present status and some key issues of the interconnection guideline for the small scale non-utility generation are briefly introduced. Demand-side indices are proposed for establishing the future flexible guideline. Margin and cost of reachable power, ability of voltage regulation and dispatchability at demand-side are discussed. Based on those demand-side indices, decision making models of utility, non-utility generation and customer are developed for supporting better realization of future flexible interconnection requirement. The Petri-Net model is applied for describing the decision making process. (authors). 6 refs. This report shall not be reproduced except in full without the written approval of Powertech Labs Inc. Report #: 14418-03-REP1 1 Oct 2003 Page 13 of 13