EPE Association: EPE-PEMC 2004 - Topic 06-1: Modelling, simulation & control in power systems

EPE-PEMC 2004 - Topic 06-1: Modelling, simulation & control in power systems
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 06: POWER SUPPLY > EPE-PEMC 2004 - Topic 06-1: Modelling, simulation & control in power systems

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   Algorithm For Software Agents To Power Supply Modeling In Baltic Region
By Nadezhda Kunicina, Anatoly Levchenkovs, Leonids Ribickis [View]
[Download]

Abstract: The purpose of this paper is to demonstrate a software agent algorithm for power supply in Baltic region. Algorithm for software agent that offers a multi -step problem solving is described.

   Algorithms, Means And Tools Of Fault Location On Transmission Lines
By Antans Sauhats, Marija Bockarjova [View]
[Download]

Abstract: This paper presents a new approach for calculation of fault location on high voltage transmission lines. The proposed fault location scheme simultaneously involves two algorithms: single-ended method based on measurements performed on one end of the power transmission line and method that in addition utilizes information obtained from the remote line end. Two protection and automation terminals provide an appropriate hardware support for proposed algorithms implementation. For data transfer between two terminals a fibre-optic link can be used. The proposed algorithms are based on modelling of the faulted line and the method of Monte-Carlo.

   Analysis Of Quality For The Slightly Turbulent Regime During The Random Oscilations In The System
By Tatjana Loman, Anna Voinovska, Viktorija Belugina [View]
[Download]

Abstract: The development of power systems and their associations creates the increasing variety of structures and conditions of those united power systems. Under these conditions it is necessary simultaneously to achieve coordination of the automatic excitation control (AEC) gains at many stations and to provide the high quality of the transient processes. Practically this becomes possible only upon transfer from the analog regulator to digital, fulfiled on the microprocessor base. In this case the new principles of adaptive regulation in highest degree corresponding to the management tasks in the modern united power systems may be realized. By study of transient processes is understood the estimation of their quality and system stability during different disturbances of its regime. The providing of the best quality of the slightly turbulent regimes due to the selection of the parameters of the automatic regulation devices and first of all, AEC of the generators, is the task of the oscillatory stability analysis.

   Application Of Data Monitoring In Creation Of The Synchronous Generator Model
By M. Miskovic, M. Mirosevic [View]
[Download]

Abstract: Model analysis input data is acquired from fault recorder and SCADA systems. The paper is focused on the identification of generator parameters and nonlinear mathematical model design. Also it demonstrates numeric processing on input data for use in modeling.

   Automatic Generation Control Of Power Systems Of Baltic States In The Conditions Of Electricity Market
By Vaclovas Azubalis, Ramunas Bikulcius, Albertas Nargelas [View]
[Download]

Abstract: Automatic generation control (AGC) is essential factor of electricity market (especially of spot market). It is one of ancillary services that must be provided on the competitive basis. AGC must take into account institutional restrictions (for example laws and interests of different states). Decentralized AGC is preferable in this case. Power system of Baltic States (PSBS) is control block of interconnected power system of Russia, Byelorussia and other systems. At the present time Russian power system performs frequency control. PSBS controls net power flow Baltic States – Russia balance. There is shortage of regulating power reserves in PSBS and exchange of AGC services among the system is urgent problem. The main task of this presentation is examination of new possibilities of implementation AGC in power systems of Baltic States that satisfy requirements of electricity market.

   Comparison Between Pulse Width Modulation Strategies In Terms Of Power Losses In A Three-Phased Inverter - Application To A Starter Generator
By Julien Hobraiche, Jean-Paul Vilain, M. Chemin [View]
[Download]

Abstract: A comparison between Space Vector Modulation and Generalized Discontinuous PWM in terms of power losses in an inverter is presented. Power losses are calculated from PSPICETM simulation results and data sheets. Each strategy is evaluated by the power losses in the inverter and torque ripple of the starter generator as a function of torque and speed.

   Description Of A State-Space Oriented Transient Network Simulation Methodology For Power Systems With Semiconductor Based Devices
By Ch. Weindl, G. Herold [View]
[Download]

Abstract: In last decade, greater changes were introduced into the structure of electrical power utilities e.g. to raise the efficiency in the operation of the power system by means of deregulating the industry and/or opening it to private competition. This trend and similar structural changes have also occurred in other industries, like the telecommunication, airline and transportation industries. The net effect of these changes necessitates that the transmission, generation and distribution systems must now adapt to a new set of rules dictated by open markets. Additionally the development of new power semiconductors has opened up novel possibilities in the field of high-power applications. The power industry has responded to these challenges in different ways. One tendency of the recent years is the development of the new power semiconductor based devices to control e.g. the active and reactive power flow. The so-called FACTS (flexible ac transmission systems) together with different structural changes in the production and transmission of electrical energy reinforce the necessity to develop new simulation and computation methods. One of the possible solutions is the state-space approach suggested in this paper.

   Development Of The Earth-Fault Indicators And Integration Into The Scada System Of Distribution Networks
By Dzintars Baranovskis, Janis Rozenkrons [View]
[Download]

Abstract: This work represents a developed universal earthfault indicator (UEI), which is allowed to detect the earth-faults at the compensated neutral cable networks and the fault detection with the fault indicators, which is connected into distribution network SCADA system by the radio signals. A pilot project “Integration of the fault indicators into the distribution network SCADA system” has reviewed which was carried out at Jelgava cable and overhead distribution networks in the year 2003.

   Distribution System And Transmission Network Power Supply Reliabilitys Estimation Software
By Antons Kutjuns, Irina Oleinikova [View]
[Download]

Abstract: Transmission and distribution networks determine the electrical energy quality, which is delivered to the costumers. This leads to the unique situation, that the shipping agent and not the producer of energy determine the quality of the product in terms of voltage quality and availability. The Laboratory of Power System Simulation (EMML) worked in the project “The Network Reliability Optimization under Liberalized Electricity Market”. New software is elaborated in this project. The software is provided for the following problems decision: 1) selection of 330, 110, 20, 10 and 6 kV switchyard type, 2) distribution network structure’s and configuration’s selection, 3) transmission network structure’s and configuration’s selection. In paper discusses methodical questions of software establishment.

   Generator-Converter Set For Mobile Power Sources
By J. Leuchter(cz), P. Bauer(nl), O. Kurka(cz), H. Polinder(nl) [View]
[Download]

Abstract: The feasibility of the mobile power source for speed with diesel generator (~3000 rpm) and high speed with gas generator (~30000 rpm) and permanent magnet synchronous generator is investigated. Three different configurations of power converter are considered. The natural question arises: should be a full controlled rectifier employed or a version with diode rectifier is satisfactory? Does the high speed generation change anything in the investigation? Different current forms for the three defined configurations with their harmonics and influence on generator are given. The efficiency of the overall system is here investigated and an optimal topology is selected. Since the EGS operates very often under low load which does not exceed in average more than 20 % of the rated permanent load, a new hypothetical topology of converter of EGS with high efficiency and low cost is suggested and studied theoretically and experimentally in the paper.

   Generators Of Independent Electric Power Plants: Electromagnetic Loads Increase And The Problems Of Generators Sustain At Dynamic Modes Of Operation.
By I. Z. Boguslawsky, Ya. B. Danilevich [View]
[Download]

Abstract: It was obtained in this work that the modern trends of independent power plants weight and overall dimensions reduction come into conflict with modern operation requirements, such as voltage drop limitation by a sudden load increase (load surge). Practical methods for solution of this problem by creation of the generator as well as in the process of its operation were suggested. Some recommendations for generator reactances XD’ and XD” reduction are also given in the article. The problem of induction motor starting by means of independent power plant generator was investigated in the work in addition.

   Linear Model Of Electrical Three-Phase Network To Desing Robust Controller
By C. Dewez, L. Rambault, J. P. Gaubert [View]
[Download]

Abstract: The aim of this paper is the modelization of a three-phase electrical network. This model is interesting from a control theory point of view. Different features of the model allow the use of tools developed for linear control theory. With the same tools, physical uncertainties due to physical parameters can be taken into account. This paper proposes to explain the model with some mathematical developments and to design a controller with simulation results.

   New Method For Complicated Automation Systems Simulation Test
By Antans Sauhats, Marija Bockarjova, Aleksandrs Dolgicers, Martins Silarajs [View]
[Download]

Abstract: This paper describes a new method for complicated automation systems testing, particularly, power systems protective relays hardware and real-time software. Test platform is based on Monte-Carlo utilization. A simulator produces voltage and current levels and protection device settings. A control program performs test case generation, waveform production, event identification, and result comparison. This paper will discuss the advantages of stochastic approach and determination of test case number necessary to achieve the desirable level of confidence.

   New Possibilities For Monitoring And Control Of Instabilities In Power Systems
By Antans Sauhats, Inesa Svalova, Andrejs Svalovs [View]
[Download]

Abstract: This paper discusses the problem of transient stability of generators connected to the transmission or distribution networks. A protection system for prevention and elimination of loss of stability in the networks are presented and new algorithms for this type of systems are proposed. The discussed methods were tested by modelling the asynchronous condition for two cases — high-voltage transmission network and distribution network that contains distributed generation. Case studies are based on commercially available power system simulation software. The coordination between the modelled devices is examined using specially designed software.

   Optimization Methods Of Low Voltage Power Networks Development Process
By Anna Mutule, Zigurds Krishans [View]
[Download]

Abstract: Newly built equipment constructions and scheduled scope of replacement works to be performed are based upon technical and economic estimations and calculations that create the background of objective necessity and rational utilization of financial resources. The major item of the study is optimal initial states method application opportunities in low voltage networks development process optimization problems and their solutions. The development of low voltage network mainly is determined by the technical criteria. In LV networks, two additional criteria are applied for limits violation estimation.

   Restoration Of Power System With Predominant Nuclear Power Generation
By V. Azubalis, A. Jonaitis, A. Nargelas, D. Virbickas [View]
[Download]

Abstract: Power system with predominant nuclear power generation restoration after the blackout is analyzed. The system with sufficient thermal power cold reserve could be restored as thermal power system with cold starting of the main part of the units. Power system restoration transients are studied. Maximum power increase rate evaluation and permissible switch on load blocks characteristics estimation is presented.

   The Analysis Of Oscillations In Models Of Heat-Hydraulic Systems
By I. A. Zolotukhin [View]
[Download]

Abstract: In this work, we examine the questions of diagnostics of heat-hydraulic systems of nuclear power stations with the purpose of revealing of the oscillatory modes, which represent danger to the equipment. On the basis of analogies between hydraulic and electric processes, the electric models of elements of hydraulic system are made. Heat-hydraulic systems are simulated with the help of multi-circuit electric systems with variable parameters. Nonlinear nature of real systems is taken into account. During the research work it was determined that oscillations have parametric nature. We examine three-contour electric circuit with variable capacity. For the analysis of oscillations the special programs realized in LabVIEW is created. The threshold characteristic is received and the conditions of stimulation of the parametrical oscillations arising in multi-circuit models are determined. It is registered that the parametric oscillations arise at the frequencies of capacity’s variation close to heterodyne frequencies of the system (doubled resonance frequencies, sum of resonance frequencies). The twocontour nonlinear electric model of heat-hydraulic system is worked out. We consider the mode of nonlinear restriction of amplitude of oscillations. The special program in LabVIEW for the analysis of the oscillations’ dynamic is created. The frequency characteristics of multi-circuit systems are constructed, and spectral structure of the oscillations is analyzed. It is registered that the nonlinear nature of the system brings positive effect to the appearing events. It reduces the probability of damage of expensive equipment at power stations and consequently reduces the probability of accident at nuclear power plants.

   Three-Level SVC Circuit With Partial Active Filter Functions For Lower Order Harmonics
By K. Matsui, H. Kojima, I. Yamamoto, M. Hasegawa, H. Mori, F. Ueda [View]
[Download]

Abstract: In this paper, various harmonic characteristics of SVC’s (Static Var Compensators) are discussed, comparison being made between symmetrical and asymmetrical modulation strategies. It is found that an extremely large scale SVC, a symmetrical modulation strategy is superior. Harmonics such as the fifth can be suppressed using the proposed SVC scheme.

EPE-PEMC 2004 - Topic 06-1: Modelling, simulation & control in power systems
You are here: EPE Documents > 04 - EPE-PEMC Conference Proceedings > EPE-PEMC 2004 - Conference > EPE-PEMC 2004 - Topic 06: POWER SUPPLY > EPE-PEMC 2004 - Topic 06-1: Modelling, simulation & control in power systems
	[return to parent folder]

	Algorithm For Software Agents To Power Supply Modeling In Baltic Region By Nadezhda Kunicina, Anatoly Levchenkovs, Leonids Ribickis	[View] [Download]
Abstract: The purpose of this paper is to demonstrate a software agent algorithm for power supply in Baltic region. Algorithm for software agent that offers a multi -step problem solving is described.

	Algorithms, Means And Tools Of Fault Location On Transmission Lines By Antans Sauhats, Marija Bockarjova	[View] [Download]
Abstract: This paper presents a new approach for calculation of fault location on high voltage transmission lines. The proposed fault location scheme simultaneously involves two algorithms: single-ended method based on measurements performed on one end of the power transmission line and method that in addition utilizes information obtained from the remote line end. Two protection and automation terminals provide an appropriate hardware support for proposed algorithms implementation. For data transfer between two terminals a fibre-optic link can be used. The proposed algorithms are based on modelling of the faulted line and the method of Monte-Carlo.

	Analysis Of Quality For The Slightly Turbulent Regime During The Random Oscilations In The System By Tatjana Loman, Anna Voinovska, Viktorija Belugina	[View] [Download]
Abstract: The development of power systems and their associations creates the increasing variety of structures and conditions of those united power systems. Under these conditions it is necessary simultaneously to achieve coordination of the automatic excitation control (AEC) gains at many stations and to provide the high quality of the transient processes. Practically this becomes possible only upon transfer from the analog regulator to digital, fulfiled on the microprocessor base. In this case the new principles of adaptive regulation in highest degree corresponding to the management tasks in the modern united power systems may be realized. By study of transient processes is understood the estimation of their quality and system stability during different disturbances of its regime. The providing of the best quality of the slightly turbulent regimes due to the selection of the parameters of the automatic regulation devices and first of all, AEC of the generators, is the task of the oscillatory stability analysis.

	Application Of Data Monitoring In Creation Of The Synchronous Generator Model By M. Miskovic, M. Mirosevic	[View] [Download]
Abstract: Model analysis input data is acquired from fault recorder and SCADA systems. The paper is focused on the identification of generator parameters and nonlinear mathematical model design. Also it demonstrates numeric processing on input data for use in modeling.

	Automatic Generation Control Of Power Systems Of Baltic States In The Conditions Of Electricity Market By Vaclovas Azubalis, Ramunas Bikulcius, Albertas Nargelas	[View] [Download]
Abstract: Automatic generation control (AGC) is essential factor of electricity market (especially of spot market). It is one of ancillary services that must be provided on the competitive basis. AGC must take into account institutional restrictions (for example laws and interests of different states). Decentralized AGC is preferable in this case. Power system of Baltic States (PSBS) is control block of interconnected power system of Russia, Byelorussia and other systems. At the present time Russian power system performs frequency control. PSBS controls net power flow Baltic States – Russia balance. There is shortage of regulating power reserves in PSBS and exchange of AGC services among the system is urgent problem. The main task of this presentation is examination of new possibilities of implementation AGC in power systems of Baltic States that satisfy requirements of electricity market.

	Comparison Between Pulse Width Modulation Strategies In Terms Of Power Losses In A Three-Phased Inverter - Application To A Starter Generator By Julien Hobraiche, Jean-Paul Vilain, M. Chemin	[View] [Download]
Abstract: A comparison between Space Vector Modulation and Generalized Discontinuous PWM in terms of power losses in an inverter is presented. Power losses are calculated from PSPICETM simulation results and data sheets. Each strategy is evaluated by the power losses in the inverter and torque ripple of the starter generator as a function of torque and speed.

	Description Of A State-Space Oriented Transient Network Simulation Methodology For Power Systems With Semiconductor Based Devices By Ch. Weindl, G. Herold	[View] [Download]
Abstract: In last decade, greater changes were introduced into the structure of electrical power utilities e.g. to raise the efficiency in the operation of the power system by means of deregulating the industry and/or opening it to private competition. This trend and similar structural changes have also occurred in other industries, like the telecommunication, airline and transportation industries. The net effect of these changes necessitates that the transmission, generation and distribution systems must now adapt to a new set of rules dictated by open markets. Additionally the development of new power semiconductors has opened up novel possibilities in the field of high-power applications. The power industry has responded to these challenges in different ways. One tendency of the recent years is the development of the new power semiconductor based devices to control e.g. the active and reactive power flow. The so-called FACTS (flexible ac transmission systems) together with different structural changes in the production and transmission of electrical energy reinforce the necessity to develop new simulation and computation methods. One of the possible solutions is the state-space approach suggested in this paper.

	Development Of The Earth-Fault Indicators And Integration Into The Scada System Of Distribution Networks By Dzintars Baranovskis, Janis Rozenkrons	[View] [Download]
Abstract: This work represents a developed universal earthfault indicator (UEI), which is allowed to detect the earth-faults at the compensated neutral cable networks and the fault detection with the fault indicators, which is connected into distribution network SCADA system by the radio signals. A pilot project “Integration of the fault indicators into the distribution network SCADA system” has reviewed which was carried out at Jelgava cable and overhead distribution networks in the year 2003.

	Distribution System And Transmission Network Power Supply Reliabilitys Estimation Software By Antons Kutjuns, Irina Oleinikova	[View] [Download]
Abstract: Transmission and distribution networks determine the electrical energy quality, which is delivered to the costumers. This leads to the unique situation, that the shipping agent and not the producer of energy determine the quality of the product in terms of voltage quality and availability. The Laboratory of Power System Simulation (EMML) worked in the project “The Network Reliability Optimization under Liberalized Electricity Market”. New software is elaborated in this project. The software is provided for the following problems decision: 1) selection of 330, 110, 20, 10 and 6 kV switchyard type, 2) distribution network structure’s and configuration’s selection, 3) transmission network structure’s and configuration’s selection. In paper discusses methodical questions of software establishment.

	Generator-Converter Set For Mobile Power Sources By J. Leuchter(cz), P. Bauer(nl), O. Kurka(cz), H. Polinder(nl)	[View] [Download]
Abstract: The feasibility of the mobile power source for speed with diesel generator (~3000 rpm) and high speed with gas generator (~30000 rpm) and permanent magnet synchronous generator is investigated. Three different configurations of power converter are considered. The natural question arises: should be a full controlled rectifier employed or a version with diode rectifier is satisfactory? Does the high speed generation change anything in the investigation? Different current forms for the three defined configurations with their harmonics and influence on generator are given. The efficiency of the overall system is here investigated and an optimal topology is selected. Since the EGS operates very often under low load which does not exceed in average more than 20 % of the rated permanent load, a new hypothetical topology of converter of EGS with high efficiency and low cost is suggested and studied theoretically and experimentally in the paper.

	Generators Of Independent Electric Power Plants: Electromagnetic Loads Increase And The Problems Of Generators Sustain At Dynamic Modes Of Operation. By I. Z. Boguslawsky, Ya. B. Danilevich	[View] [Download]
Abstract: It was obtained in this work that the modern trends of independent power plants weight and overall dimensions reduction come into conflict with modern operation requirements, such as voltage drop limitation by a sudden load increase (load surge). Practical methods for solution of this problem by creation of the generator as well as in the process of its operation were suggested. Some recommendations for generator reactances XD’ and XD” reduction are also given in the article. The problem of induction motor starting by means of independent power plant generator was investigated in the work in addition.

	Linear Model Of Electrical Three-Phase Network To Desing Robust Controller By C. Dewez, L. Rambault, J. P. Gaubert	[View] [Download]
Abstract: The aim of this paper is the modelization of a three-phase electrical network. This model is interesting from a control theory point of view. Different features of the model allow the use of tools developed for linear control theory. With the same tools, physical uncertainties due to physical parameters can be taken into account. This paper proposes to explain the model with some mathematical developments and to design a controller with simulation results.

	New Method For Complicated Automation Systems Simulation Test By Antans Sauhats, Marija Bockarjova, Aleksandrs Dolgicers, Martins Silarajs	[View] [Download]
Abstract: This paper describes a new method for complicated automation systems testing, particularly, power systems protective relays hardware and real-time software. Test platform is based on Monte-Carlo utilization. A simulator produces voltage and current levels and protection device settings. A control program performs test case generation, waveform production, event identification, and result comparison. This paper will discuss the advantages of stochastic approach and determination of test case number necessary to achieve the desirable level of confidence.

	New Possibilities For Monitoring And Control Of Instabilities In Power Systems By Antans Sauhats, Inesa Svalova, Andrejs Svalovs	[View] [Download]
Abstract: This paper discusses the problem of transient stability of generators connected to the transmission or distribution networks. A protection system for prevention and elimination of loss of stability in the networks are presented and new algorithms for this type of systems are proposed. The discussed methods were tested by modelling the asynchronous condition for two cases — high-voltage transmission network and distribution network that contains distributed generation. Case studies are based on commercially available power system simulation software. The coordination between the modelled devices is examined using specially designed software.

	Optimization Methods Of Low Voltage Power Networks Development Process By Anna Mutule, Zigurds Krishans	[View] [Download]
Abstract: Newly built equipment constructions and scheduled scope of replacement works to be performed are based upon technical and economic estimations and calculations that create the background of objective necessity and rational utilization of financial resources. The major item of the study is optimal initial states method application opportunities in low voltage networks development process optimization problems and their solutions. The development of low voltage network mainly is determined by the technical criteria. In LV networks, two additional criteria are applied for limits violation estimation.

	Restoration Of Power System With Predominant Nuclear Power Generation By V. Azubalis, A. Jonaitis, A. Nargelas, D. Virbickas	[View] [Download]
Abstract: Power system with predominant nuclear power generation restoration after the blackout is analyzed. The system with sufficient thermal power cold reserve could be restored as thermal power system with cold starting of the main part of the units. Power system restoration transients are studied. Maximum power increase rate evaluation and permissible switch on load blocks characteristics estimation is presented.

	The Analysis Of Oscillations In Models Of Heat-Hydraulic Systems By I. A. Zolotukhin	[View] [Download]
Abstract: In this work, we examine the questions of diagnostics of heat-hydraulic systems of nuclear power stations with the purpose of revealing of the oscillatory modes, which represent danger to the equipment. On the basis of analogies between hydraulic and electric processes, the electric models of elements of hydraulic system are made. Heat-hydraulic systems are simulated with the help of multi-circuit electric systems with variable parameters. Nonlinear nature of real systems is taken into account. During the research work it was determined that oscillations have parametric nature. We examine three-contour electric circuit with variable capacity. For the analysis of oscillations the special programs realized in LabVIEW is created. The threshold characteristic is received and the conditions of stimulation of the parametrical oscillations arising in multi-circuit models are determined. It is registered that the parametric oscillations arise at the frequencies of capacity’s variation close to heterodyne frequencies of the system (doubled resonance frequencies, sum of resonance frequencies). The twocontour nonlinear electric model of heat-hydraulic system is worked out. We consider the mode of nonlinear restriction of amplitude of oscillations. The special program in LabVIEW for the analysis of the oscillations’ dynamic is created. The frequency characteristics of multi-circuit systems are constructed, and spectral structure of the oscillations is analyzed. It is registered that the nonlinear nature of the system brings positive effect to the appearing events. It reduces the probability of damage of expensive equipment at power stations and consequently reduces the probability of accident at nuclear power plants.

	Three-Level SVC Circuit With Partial Active Filter Functions For Lower Order Harmonics By K. Matsui, H. Kojima, I. Yamamoto, M. Hasegawa, H. Mori, F. Ueda	[View] [Download]
Abstract: In this paper, various harmonic characteristics of SVC’s (Static Var Compensators) are discussed, comparison being made between symmetrical and asymmetrical modulation strategies. It is found that an extremely large scale SVC, a symmetrical modulation strategy is superior. Harmonics such as the fifth can be suppressed using the proposed SVC scheme.