This paper presents the software SIMPLEX, designed to assist the planner in the challenge of plan... more This paper presents the software SIMPLEX, designed to assist the planner in the challenge of planning the expansion of electricity distribution systems. The software was developed as part of a research and development project and uses data from various utility legacy systems such as GIS, SCADA and OMS to centralize a range of tools used in the expansion planning process. In addition to the adopted methodology, a case study is presented where all the stages of the planning process are covered with the aid of the software. The case study concludes at the resource optimization stage for multiple planning study regions, one of SIMPLEX's innovative features. Resumo: Esse artigo apresenta um software, denominado SIMPLEX, de auxílio ao planejador no desafio de planejamento da expansão de sistemas de distribuição de energia elétrica. O software foi desenvolvido no âmbito de projeto de pesquisa e desenvolvimento e utiliza dados provenientes de diversos sistemas legados da concessionária,...
This paper presents a specific application of a computational system to model general constrained... more This paper presents a specific application of a computational system to model general constrained decision problems. This application is concerned with the reconfiguration of distribution systems following a fault in a given network section. Once the fault is located one should isolate a minimum part of the system through the switching equipment and try to re-energize the customers - located further to the opened switch(es) - by feeder interconnection switches. This problem is combinatorial in nature and an extremely large number of possible solutions can be identified when dealing with networks of practical size. A heuristic search approach allows the evaluation of optimized/feasible solutions in an efficient way. Uncertainty, imprecision and subjectivity aspects are dealt with by the use of fuzzy sets theory. Multiple objectives regarding minimum number of switching operations and maximization of a technical index - including voltage drop and loading - are also considered in the f...
In power distribution systems, short-circuit events imply long service response time, affecting t... more In power distribution systems, short-circuit events imply long service response time, affecting the quality of service. Although many research works propose fault location methodologies, which are based on meta-heuristics, artificial intelligence and travelling waves, most power utilities do not have the data requested by such approaches. Consequently, maintenance crews locate faults through field searches, considering the operation of protection devices and affected customers' phone calls, characterizing a procedure that may last some hours. This work proposes a practical fault location methodology, considering the current scenario of few metering data concerning the short-circuit events. Based on case studies results, the proposed methodology is considered effective. It may be executed in few seconds and leads to satisfactory results. Resumo: Em sistemas de distribuição, eventos de curto-circuito demandam longos tempos de atendimento, afetando a qualidade do serviço. Embora di...
IEEE Power Engineering Society General Meeting, 2005
This paper proposes a new probabilistic method to evaluate power distribution electrical performa... more This paper proposes a new probabilistic method to evaluate power distribution electrical performance. Electrical performance is assumed to be the evaluation of network congestion parameters, losses and voltage level. The proposed method is suitable for off-line applications and it considers steady state performance only. The electrical performance estimation is formulated as a multiobjective optimization problem where the objective functions correspond
Environmental science and pollution research international, Jan 27, 2018
The present paper proposes a methodology based on the implementation and assessment of autoregres... more The present paper proposes a methodology based on the implementation and assessment of autoregressive (AR) solar radiation models for generating synthetic series and providing guidance on bidding strategies for power purchase agreements. The work considered conventional and periodic AR models with different lag orders, assessing the models against real solar radiation measurements. The synthetic series generation process developed 1000 1-year monthly solar radiation scenarios that were later employed for simulating electric energy production and power purchase agreement models. This application allowed one to evaluate the risk associated with the energy supply security, supporting bidding strategies in energy auctions. A real study case is also illustrated in detail, referring to a spot in the Brazilian best irradiance area.
2016 17th International Conference on Harmonics and Quality of Power (ICHQP), 2016
This paper presents a computerized system for detection of high impedance faults (HIF) in MV dist... more This paper presents a computerized system for detection of high impedance faults (HIF) in MV distribution feeders. This system has been developed in an R&D Project of AES Eletrpaulo. A HIF occurs when an energized conductor makes contact with objects with a high resistance and there are no significant increases in current. It is common to associate HIF to situations in which there is fallen primary conductor, creating risk of fatal accidents due its proximity to people. This is the main focus of this project. This type of fault cannot be detected by traditional overcurrent protection devices. The method developed herein relies on the use of variables obtained from power quality meters installed at the feeders in the substation, measuring quantities such as current harmonics, sequence components amongst others, with which some indices are calculated to detect the occurrence of a HIF event using artificial neural networks (ANN). The proposed system was implemented and installed in an AES Eletropaulo substation.
This paper presents the software SIMPLEX, designed to assist the planner in the challenge of plan... more This paper presents the software SIMPLEX, designed to assist the planner in the challenge of planning the expansion of electricity distribution systems. The software was developed as part of a research and development project and uses data from various utility legacy systems such as GIS, SCADA and OMS to centralize a range of tools used in the expansion planning process. In addition to the adopted methodology, a case study is presented where all the stages of the planning process are covered with the aid of the software. The case study concludes at the resource optimization stage for multiple planning study regions, one of SIMPLEX's innovative features. Resumo: Esse artigo apresenta um software, denominado SIMPLEX, de auxílio ao planejador no desafio de planejamento da expansão de sistemas de distribuição de energia elétrica. O software foi desenvolvido no âmbito de projeto de pesquisa e desenvolvimento e utiliza dados provenientes de diversos sistemas legados da concessionária,...
This paper presents a specific application of a computational system to model general constrained... more This paper presents a specific application of a computational system to model general constrained decision problems. This application is concerned with the reconfiguration of distribution systems following a fault in a given network section. Once the fault is located one should isolate a minimum part of the system through the switching equipment and try to re-energize the customers - located further to the opened switch(es) - by feeder interconnection switches. This problem is combinatorial in nature and an extremely large number of possible solutions can be identified when dealing with networks of practical size. A heuristic search approach allows the evaluation of optimized/feasible solutions in an efficient way. Uncertainty, imprecision and subjectivity aspects are dealt with by the use of fuzzy sets theory. Multiple objectives regarding minimum number of switching operations and maximization of a technical index - including voltage drop and loading - are also considered in the f...
In power distribution systems, short-circuit events imply long service response time, affecting t... more In power distribution systems, short-circuit events imply long service response time, affecting the quality of service. Although many research works propose fault location methodologies, which are based on meta-heuristics, artificial intelligence and travelling waves, most power utilities do not have the data requested by such approaches. Consequently, maintenance crews locate faults through field searches, considering the operation of protection devices and affected customers' phone calls, characterizing a procedure that may last some hours. This work proposes a practical fault location methodology, considering the current scenario of few metering data concerning the short-circuit events. Based on case studies results, the proposed methodology is considered effective. It may be executed in few seconds and leads to satisfactory results. Resumo: Em sistemas de distribuição, eventos de curto-circuito demandam longos tempos de atendimento, afetando a qualidade do serviço. Embora di...
IEEE Power Engineering Society General Meeting, 2005
This paper proposes a new probabilistic method to evaluate power distribution electrical performa... more This paper proposes a new probabilistic method to evaluate power distribution electrical performance. Electrical performance is assumed to be the evaluation of network congestion parameters, losses and voltage level. The proposed method is suitable for off-line applications and it considers steady state performance only. The electrical performance estimation is formulated as a multiobjective optimization problem where the objective functions correspond
Environmental science and pollution research international, Jan 27, 2018
The present paper proposes a methodology based on the implementation and assessment of autoregres... more The present paper proposes a methodology based on the implementation and assessment of autoregressive (AR) solar radiation models for generating synthetic series and providing guidance on bidding strategies for power purchase agreements. The work considered conventional and periodic AR models with different lag orders, assessing the models against real solar radiation measurements. The synthetic series generation process developed 1000 1-year monthly solar radiation scenarios that were later employed for simulating electric energy production and power purchase agreement models. This application allowed one to evaluate the risk associated with the energy supply security, supporting bidding strategies in energy auctions. A real study case is also illustrated in detail, referring to a spot in the Brazilian best irradiance area.
2016 17th International Conference on Harmonics and Quality of Power (ICHQP), 2016
This paper presents a computerized system for detection of high impedance faults (HIF) in MV dist... more This paper presents a computerized system for detection of high impedance faults (HIF) in MV distribution feeders. This system has been developed in an R&D Project of AES Eletrpaulo. A HIF occurs when an energized conductor makes contact with objects with a high resistance and there are no significant increases in current. It is common to associate HIF to situations in which there is fallen primary conductor, creating risk of fatal accidents due its proximity to people. This is the main focus of this project. This type of fault cannot be detected by traditional overcurrent protection devices. The method developed herein relies on the use of variables obtained from power quality meters installed at the feeders in the substation, measuring quantities such as current harmonics, sequence components amongst others, with which some indices are calculated to detect the occurrence of a HIF event using artificial neural networks (ANN). The proposed system was implemented and installed in an AES Eletropaulo substation.
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Papers by Nelson Kagan