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05033 Distribution system feeder cold load pickup model
06
Electric power generation and utilisation (scientific, technical)
Design of an artificial neural network for fast line 96105029 flow contingency ranking Ghosh, S. and Chowdhury, B. H. Electrical Power & Energy Systems, Jun. 1996, 18, (S), 271-277. A three-layer perceptron artifical neural network with back propagation learning technique is designed for line flow contingency ranking. Two new indices - a severity index and a margin index for lineflow - are defined. A regression-based correlation technique is used to select training parameters for the neural network. The proposed method has been tested for the IEEE 118-bus test system. Results show that the contivgency rankings by the proposed method are comparable to results obtained by the classical performance index method. An advantage of the proposed method is its applicability in the control centre environment. Development of a graphical user interface for a 96105030 real-time power system simulator Rochefort, M. er al., Electric Power Sysrems Res., Mar. 1996, 36, (3), 203-210. The project presented in this paper began in 1993. It consists primarily in a graphical user interface for the real-time simulator at IREQ. It is based on a single-line schematic display and it uses the paradigm of model-viewcontroller objects. The first phase of the project includes a schematic editor with all the functionality of a generic editor (colour, zoom, connectivity, etc.) combined with the effective control of elements of the real-time simulator. The next phase will include support for three-phase representation and integration to the network database of the real-time simulator at IREQ. This work has permitted the authors to explore and master object concepts that will improve the development and evolution of graphical user interfaces at IREQ. Digital network model for tests of different equip96105031 ment in electric power systems Friedland, R. et al., Electric Power Sysfems Rex, Mar. 1996, 36, (3), 197-202. Describes the interface developed for real-time communication, DlNEMO (Digital Network Model). Is has been used for different applications in the last five years. This digital network model comprises all necessary power system hardware components and communication betaeen different computers and any real equipment. Furthermore it is possible to perform digital real-time simulations for hardware-in-the-loop testing of real equipment. 96/05032
A digital technique for stator winding protection of synchronous generators Sidhu. T. S. er al., Elecrric Power Sjsrems Rex, Jan. 1996, 36, (1). 45-55. The paper describes a digital technique for detecting internal faults in stator windings of synchronous generators. The technique uses positive- and negative-sequence models of the synchronous generator, and voltages and currents measured at the generator terminals. It does not need information concerning the machine parameters and is applicable to all types of generators, irrespective of their size. Fault discrimination characteristics and a digital algorithm based on the proposed technique are described. 96105033 ;;;_ui6;. C.
Distribution system feeder cold load pickup model et al., Elecrric Power Systems Res., Mar. 1996, 36, (3).
In order 10 maintain a balance between the generation and load during service restoration, it is important to have mathematical models that can predict the load that will be present at various locations of the system. A regression approach supported by voluminous feeder load measurement data collected during large-scale rotating interruptions is presented. Regression models are proposed 10 estimate the feeder and substation cold load pickups after scheduled outages. A dynamic interpretation of the load-flow Jacobian 96105034 singularity for voltage stability analysis Bompard, E. er al., Electrical Power & Energy Sysfems, Aug. 1996, 18, (6), 385-395. In voltage stability analysis, both static and dynamic approaches are used to evaluate the system critical conditions. The static approach is based on the standard load-flow equations. For small-disturbance analysis, the dynamic approach is based on the eigenvalue computation of the linearized system, while for large-disturbance analysis a complete time-domain simulation is required. However, both the equilibrium point around which linearization is performed and the initial conditions for the simulation are computed by a procedure which uses the standard load-flow equations. 96105035 Dynamic properties of bulk power interconnections Voropai, N. 1. and Shutov, G. V. Elecrricul Power & Euergy Sysrems, Mar. 1996, 18, (3), 161-165. The paper describes changes in dynamic properties of the present-day bulk electric power systems (EPS) in the course of their development, on the basis of operating experience and numerous studies. The character, reasons and consequences of these changes are analysed. The dynamic properties of EPS are becoming worse loading to a decrease in the reliability of consumer supply. Consideration is given to the emergency control measures that reduce the negative consequences of consumers in such systems.
354
Fuel and Energy
Abstracts
September
1996
An efficient approach to identi 96105036 and integrate demand-side management on electric ut7 lity generation planning Osareh. A. R. et al., Electric PowerSystems Res.. Jan. 1996. 36. (1). 3-11. The electric utility .planning environment has changed dramatichljy over the last few years. Utilities now need to include a wider variety of resources to meet the demand growth and increasing technical, economic, and environmental constraints. As a result, demand-side management (DSM) is widely implemented as part of the generation planning process. Since DSM programmes have immediate benefits with respect to system reliability and financial performance, it is necessary that probabilistic production costing and reliability analysis be performed for the available DSM options. An efficient approach is presented which utilizes the eigenvector method and a new load duration curve. Experiences on using a workstation cluster to 96105037 implement a real-time digital transient network analyzer Barretta, L. er al., Electric Power Systems Res., Mar. 1996, 36, (3), 175-180. A feasibility study of a real-time digital simulator, capable of analyzing electrical transients in generation, transmission and distribution systems, led to the identification of a cluster of high-end workstations, interconnected by means of a high-performance communication and I/O system, as the most promising architectural solution. To evaluate the possibility of matching the real-time requirements of such a simulator, a testbed has been set up, constituted by two workstations sharing an external VME bus through suitable bus adapters. Fast contingent evaluation by means of the 96105030 improved adjoint network met t: od Gubina, F. er al., Electrical Power & Energy Systems, Aug. 1996, 18, (6), 377-383. In this paper, an improvement of the adjoint network (AN) method based on the Tellegen theorem for calculation of power system variables following various contingencies is presented. A new model of PV nodes is developed and the response of PV Modes to line as well as generator outages is modelled accordingly. Furthermore, an improved computational scheme is derived that enables a first single step evaluation of post contingency power system variables. Example cases of test and practical systems show that the improved adjoint network (IAN) method offers an efficient tool for on-line contingency analysis due to its improved accuracy and computational effort in comparison with the widely accepted 1PlQ approach based on fast decoupled power flow. 96105039
Fast distribution power flow using multiprocessors Fukuyama. Y. et al., Electrical Power & Energy Systems, Jun. 1996, 18, (S), 331-337. The paper develops a parallel method for fast distribution power flow studies using multi-processors. The method belongs to the class of coursegrain and exhibits good convergence characteristic over a wide range of r/x ratio of distribution lines. The method can be applied to radial distribution systems. It uses only active and reactive power injections at the main feeder and at laterals as state variables; thus reducing the number of state variables. Radial distribution networks are mapped into the tree structure of a multi-processor system for allocating processes. The forward/backward sweep approach is realized by communication between the root processor and leaf processors. The proposed method is evaluated on various distribution systems including an actual system with promising results. 96105040
Fibre optics standardisation Barden, L. Lfg., Feb. 1996, 16, (l), 16-20. Discusses the standardisation of fibre optic lighting, hollow light guides and filled guides. Describes the efforts by IALD at standardisation, including agreeing on a title for the technology, identification of the technologies and agreement on universal definitions.
Fuel cells look good under pressure 96105041 MPS, Modern Power Systems, Jun. 1996, 16, (6), 23, 25-26. Describes the development of a programme being co-sponsored by Westinghouse and the US Department of Energy which has recently demonstrated enhanced prospects for the ultimate commercial success of the ‘tubular’ solid oxide fuel cell. The DOE reported that recent improvements in this configuration have boosted the electrical output of the all-solid-state ceramic fuel cell by more than a third. Generating interest 96/05042 Mill, A. er al., Bldg. Serv. ClBSE J., Feb. 1996, 18, (2), 38-39. A review of two papers given at the 1995 In-Power Conference. The hire of generation capacity in the form of medium-term hire of large plant to meet short-term generation needs is discussed. The second paper discusses the technical issues involved in connecting embedded power plants to their associated industrial electrical networks. 96105043
A guiding light Littlefair, P. Bldg. Serv. CIBSE J., Mar. 1996, 18, (3), 4.546. Discusses the use of innovative daylighting systems in buildings.
Electric power generation and utilisation (scientific, technical)
Design of an artificial neural network for fast line 96105029 flow contingency ranking Ghosh, S. and Chowdhury, B. H. Electrical Power & Energy Systems, Jun. 1996, 18, (S), 271-277. A three-layer perceptron artifical neural network with back propagation learning technique is designed for line flow contingency ranking. Two new indices - a severity index and a margin index for lineflow - are defined. A regression-based correlation technique is used to select training parameters for the neural network. The proposed method has been tested for the IEEE 118-bus test system. Results show that the contivgency rankings by the proposed method are comparable to results obtained by the classical performance index method. An advantage of the proposed method is its applicability in the control centre environment. Development of a graphical user interface for a 96105030 real-time power system simulator Rochefort, M. er al., Electric Power Sysrems Res., Mar. 1996, 36, (3), 203-210. The project presented in this paper began in 1993. It consists primarily in a graphical user interface for the real-time simulator at IREQ. It is based on a single-line schematic display and it uses the paradigm of model-viewcontroller objects. The first phase of the project includes a schematic editor with all the functionality of a generic editor (colour, zoom, connectivity, etc.) combined with the effective control of elements of the real-time simulator. The next phase will include support for three-phase representation and integration to the network database of the real-time simulator at IREQ. This work has permitted the authors to explore and master object concepts that will improve the development and evolution of graphical user interfaces at IREQ. Digital network model for tests of different equip96105031 ment in electric power systems Friedland, R. et al., Electric Power Sysfems Rex, Mar. 1996, 36, (3), 197-202. Describes the interface developed for real-time communication, DlNEMO (Digital Network Model). Is has been used for different applications in the last five years. This digital network model comprises all necessary power system hardware components and communication betaeen different computers and any real equipment. Furthermore it is possible to perform digital real-time simulations for hardware-in-the-loop testing of real equipment. 96/05032
A digital technique for stator winding protection of synchronous generators Sidhu. T. S. er al., Elecrric Power Sjsrems Rex, Jan. 1996, 36, (1). 45-55. The paper describes a digital technique for detecting internal faults in stator windings of synchronous generators. The technique uses positive- and negative-sequence models of the synchronous generator, and voltages and currents measured at the generator terminals. It does not need information concerning the machine parameters and is applicable to all types of generators, irrespective of their size. Fault discrimination characteristics and a digital algorithm based on the proposed technique are described. 96105033 ;;;_ui6;. C.
Distribution system feeder cold load pickup model et al., Elecrric Power Systems Res., Mar. 1996, 36, (3).
In order 10 maintain a balance between the generation and load during service restoration, it is important to have mathematical models that can predict the load that will be present at various locations of the system. A regression approach supported by voluminous feeder load measurement data collected during large-scale rotating interruptions is presented. Regression models are proposed 10 estimate the feeder and substation cold load pickups after scheduled outages. A dynamic interpretation of the load-flow Jacobian 96105034 singularity for voltage stability analysis Bompard, E. er al., Electrical Power & Energy Sysfems, Aug. 1996, 18, (6), 385-395. In voltage stability analysis, both static and dynamic approaches are used to evaluate the system critical conditions. The static approach is based on the standard load-flow equations. For small-disturbance analysis, the dynamic approach is based on the eigenvalue computation of the linearized system, while for large-disturbance analysis a complete time-domain simulation is required. However, both the equilibrium point around which linearization is performed and the initial conditions for the simulation are computed by a procedure which uses the standard load-flow equations. 96105035 Dynamic properties of bulk power interconnections Voropai, N. 1. and Shutov, G. V. Elecrricul Power & Euergy Sysrems, Mar. 1996, 18, (3), 161-165. The paper describes changes in dynamic properties of the present-day bulk electric power systems (EPS) in the course of their development, on the basis of operating experience and numerous studies. The character, reasons and consequences of these changes are analysed. The dynamic properties of EPS are becoming worse loading to a decrease in the reliability of consumer supply. Consideration is given to the emergency control measures that reduce the negative consequences of consumers in such systems.
354
Fuel and Energy
Abstracts
September
1996
An efficient approach to identi 96105036 and integrate demand-side management on electric ut7 lity generation planning Osareh. A. R. et al., Electric PowerSystems Res.. Jan. 1996. 36. (1). 3-11. The electric utility .planning environment has changed dramatichljy over the last few years. Utilities now need to include a wider variety of resources to meet the demand growth and increasing technical, economic, and environmental constraints. As a result, demand-side management (DSM) is widely implemented as part of the generation planning process. Since DSM programmes have immediate benefits with respect to system reliability and financial performance, it is necessary that probabilistic production costing and reliability analysis be performed for the available DSM options. An efficient approach is presented which utilizes the eigenvector method and a new load duration curve. Experiences on using a workstation cluster to 96105037 implement a real-time digital transient network analyzer Barretta, L. er al., Electric Power Systems Res., Mar. 1996, 36, (3), 175-180. A feasibility study of a real-time digital simulator, capable of analyzing electrical transients in generation, transmission and distribution systems, led to the identification of a cluster of high-end workstations, interconnected by means of a high-performance communication and I/O system, as the most promising architectural solution. To evaluate the possibility of matching the real-time requirements of such a simulator, a testbed has been set up, constituted by two workstations sharing an external VME bus through suitable bus adapters. Fast contingent evaluation by means of the 96105030 improved adjoint network met t: od Gubina, F. er al., Electrical Power & Energy Systems, Aug. 1996, 18, (6), 377-383. In this paper, an improvement of the adjoint network (AN) method based on the Tellegen theorem for calculation of power system variables following various contingencies is presented. A new model of PV nodes is developed and the response of PV Modes to line as well as generator outages is modelled accordingly. Furthermore, an improved computational scheme is derived that enables a first single step evaluation of post contingency power system variables. Example cases of test and practical systems show that the improved adjoint network (IAN) method offers an efficient tool for on-line contingency analysis due to its improved accuracy and computational effort in comparison with the widely accepted 1PlQ approach based on fast decoupled power flow. 96105039
Fast distribution power flow using multiprocessors Fukuyama. Y. et al., Electrical Power & Energy Systems, Jun. 1996, 18, (S), 331-337. The paper develops a parallel method for fast distribution power flow studies using multi-processors. The method belongs to the class of coursegrain and exhibits good convergence characteristic over a wide range of r/x ratio of distribution lines. The method can be applied to radial distribution systems. It uses only active and reactive power injections at the main feeder and at laterals as state variables; thus reducing the number of state variables. Radial distribution networks are mapped into the tree structure of a multi-processor system for allocating processes. The forward/backward sweep approach is realized by communication between the root processor and leaf processors. The proposed method is evaluated on various distribution systems including an actual system with promising results. 96105040
Fibre optics standardisation Barden, L. Lfg., Feb. 1996, 16, (l), 16-20. Discusses the standardisation of fibre optic lighting, hollow light guides and filled guides. Describes the efforts by IALD at standardisation, including agreeing on a title for the technology, identification of the technologies and agreement on universal definitions.
Fuel cells look good under pressure 96105041 MPS, Modern Power Systems, Jun. 1996, 16, (6), 23, 25-26. Describes the development of a programme being co-sponsored by Westinghouse and the US Department of Energy which has recently demonstrated enhanced prospects for the ultimate commercial success of the ‘tubular’ solid oxide fuel cell. The DOE reported that recent improvements in this configuration have boosted the electrical output of the all-solid-state ceramic fuel cell by more than a third. Generating interest 96/05042 Mill, A. er al., Bldg. Serv. ClBSE J., Feb. 1996, 18, (2), 38-39. A review of two papers given at the 1995 In-Power Conference. The hire of generation capacity in the form of medium-term hire of large plant to meet short-term generation needs is discussed. The second paper discusses the technical issues involved in connecting embedded power plants to their associated industrial electrical networks. 96105043
A guiding light Littlefair, P. Bldg. Serv. CIBSE J., Mar. 1996, 18, (3), 4.546. Discusses the use of innovative daylighting systems in buildings.