• 전기학회논문지
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• 제57권1호
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• pp.8-13
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• 2008

This paper presents auto-reclosing algorithms with reference to power system stability based on MAS(Multi-Agent System). And this paper shows auto-reclosing algorithms considering power system stability. It includes the variable dead time, optimal reclosing, sequential reclosing, emergency extended equal-area criterion(EEEAC) algorithm, and modified EEEAC algorithm. This paper divides Auto-reclosing algorithms into respectively agents according to their tasks. A separated agent is merely a software entity that is situated in some environment and is able to autonomously react to changes in the environment. And all the simulations in this parer were tested by EMTP MODELS.

• International Journal of Control, Automation, and Systems
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• 제6권5호
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• pp.651-659
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• 2008

Autoreclosing techniques have been used in power systems to maintain system stability and continuity of supply. Environmental and economical issues have driven significant increases in the development of distributed generation (DG). DG connected to distribution systems, however, may impose negative influences with respect to power quality, protection, and stability, because DG can cause some challenges to protection, especially to reclosing. For this reason, in order to improve the reliability and safety of the distribution system, the rules and guidelines suggest that the DG system needs to be rapidly disconnected from the system before reclosing. We present, in this paper, an adaptive reclosing algorithm considering the DG. The algorithm consists of an angle oscillation's judgment, the emergency extended equal-area criterion (EEEAC), the calculation of an optimal reclosing time, and a reconnection algorithm. Our simulation results for three different DG technologies with Electromagnetic Transient Program (EMTP) indicate that we can maintain transient stability while the DG is protected against disturbances.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.270-271
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• 2006

This paper presents the reclosing algorithm considering the DG(Distributed Generation). The algorithm consists of angle oscillation's judgment, EEEAC(Emergency Extended Equal-Area Criterion), calculation of optimal reclosing time and reconnection algorithm. The simulation is implemented for the three different DG technologies by using EMTP MODELS.

• 전기학회논문지
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• 제56권2호
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• pp.227-232
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• 2007

The autoreclosing is applied to power system for maintaining system stability and continuity of supply. Developments on distributed generation(DG) grows significantly by environmental issues and economical issues. If the DG is connected to distribution system, the DG influences the technical aspects such as power quality, protection and stability. It causes the challenges to protection, especially to reclosing. In order to achieve reliability and safety of the distribution system, the rules and guidelines suggest that the DG units should be rapidly disconnected from the network before the reclosing. If the DG is disconnected whenever the fault occurs, it cannot be utilized effectively. This paper presents the adaptive reclosing algorithm considering the DG. The algorithm consists of angle oscillation's judgment, EEEAC(Emergency Expanded Equal-Area Criterion), calculation of optimal reclosing time and re-connection algorithm. The simulation is implemented for the DG technology by using EMTP MODELS. The simulation results show that the transient stability is maintained and the DG is protected against disturbance.

• Journal of Electrical Engineering and Technology
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• 제1권1호
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• pp.8-15
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• 2006

Since the power swing depends on the operating time of the relay, the swing's magnitude can be reduced by an autoreclosure relaying system with an optimal reclosing algorithm. This paper proposes a method for stability improvement using optimal reclosure relaying. An optimal reclosure algorithm is applied to identify both temporary and permanent faults, and to predict system stability by applying WAM and high speed communication technology. It provides optimal control by predicting and determining the degree of stability, considering the real time transient stability using EEEAC. For temporary faults, the algorithm determines the system's stability and either recloses optimally for stable systems, or inserts series capacitance before optimal reclosure for unstable systems. It also applies an optimal reclosure algorithm to minimize shock and damage to the power system when reclosure fails due to permanent faults.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.795-803
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• 2015

Autoreclosure provides a means of improving power transmitting ability and system stability. Conventional reclosure adopts the fixed dead time interval strategy, where the reclosure is activated after a time delay to restore the system to normal as quickly as possible without regard to the system conditions. However, these simple techniques cannot provide optimal operating performance. This paper presents an adaptive autoreclosure algorithm including variable dead time, optimal reclosure, phase-by-phase reclosure and emergency extended equal-area criterion (EEEAC) algorithm in order to improve system stability. The reclosure algorithm performs the operations that are attuned to the power system conditions. The proposed adaptive reclosure algorithm is verified and tested using ATP/EMTP MODELS, and the simulation results show that the system oscillations are reduced and the transient stability is enhanced by employing the proposed adaptive reclosure algorithm.

• 대한전기학회논문지:전력기술부문A
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• 제52권12호
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• pp.698-704
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• 2003

Autoreclosure provides a mean of improving power transmitting ability and system stability. The conventional reclosure adopts the fixed dead time interval strategy, that is, the reclosure is activated after a time delay to restore the system to normal as quickly as possible without regard to the system conditions, however, these simple techniques cannot give the optimal operating performance. For this reason, various adaptive reclosure algorithms have been proposed recently, This paper presents an adaptive autoreclosure algorithm including the variable dead time, optimal reclosure, sequential reclosure and emergency extended equal-area criterion (EEAC) algorithm in order to improve the system stability. The reclosure algorithm performs out the operations that are attuned to the power system conditions. The proposed adaptive reclosure algorithm is verified and tested by using EMTP MODELS, and the simulation results show that the system oscillations are reduced and the transient stability is enhanced by employing the proposed adaptive reclosure algorithm.

• 한국전자통신학회논문지
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• 제17권3호
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• pp.417-422
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• 2022

선로를 따라 흐르는 전력흐름은 장기간에 걸쳐서 차단되지 않는 연속성을 갖는 것이 바람직하다. 배전선로에서 재폐로기의 최적 기준은 전력계통의 신뢰성을 개선하는 것으로 알려져 있으며, 배전계통에서 보호기능은 이러한 재폐로기의 수량과 위치가 매우 중요하다. 본 연구에서는 배전망 사고 동안 발생되는 손실을 줄이기 위하여 재폐로 동작 횟수를 포함한 보호기법의 사용 효과를 검토한다. 본 연구의 최종 목적은 표준 배전망에 대한 PSCAD/EMTDC의 모의데이터를 기반으로 사고전류 조건과 재폐로 동작 횟수를 결정하는 것이다. 피더의 보호기능인 재폐로기에서 동작횟수 결정은 배전망의 최적 운영과 신뢰성 확보에 도움이 된다.