• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.8_9
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• 2009

This paper shows us the analysis of the Recloser-Fuse coordination in power distribution system. Recloser has been installed with fuse to coordinate in power distribution system to protect against fault current efficiently. However, in power distribution system with SFCL, fault current couldn't be clear if occurred it as the operation of the Recloser-Fuse coordination couldn't be done. Therefore, this paper analysed the operation of the Recloser-Fuse coordination and found the method of the Recloser-Fuse coordination in power distribution system with SFCL using PSCAD/EMTDC.

• 산업기술연구
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• 제31권B호
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• pp.17-21
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• 2011

Since the railway passenger services have been recognized as important factor for success in railway, electrical energy consumption in railway station for high quality service has greatly increased. Furthermore, the number of the private railway station has gradually increased. Therefore, the operation conditions for railway power distribution system is dramatically changed in comparison with the past. So, this paper proposes the optimal construction method for railway power distribution system considering economical efficiency and the reliability of power supply to establish the railway power distribution system standard for the future railway industry.

• 전기학회논문지
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• 제65권11호
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• pp.1800-1805
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• 2016

The micro-grid designed as bipolar ${\pm}750V$ low-voltage DC power distribution system demonstrated by KEPRI, demands interconnection of a number of small decentralized power source including variable renewable generator. Therefore, variable researches for the influence of interconnection with the bipolar typed DC grid and these variable power sources are required for superior quality of power distribution. Renewable power generation simulators for the bipolar ${\pm}750V$ low-voltage DC power distribution system are necessary for such researches. In this paper, we carry out a research on the photovoltaic simulator that be actually able to interconnect with a bipolar ${\pm}750V$ low-voltage micro-grid. Simulator for this research is not only able to simulate photovoltaic generation according to weather informations and PV modules characteristics, but also contribute to stabilization of bipolar ${\pm}750V$ low-voltage of the system. Therefore, the simulator was designed to develop a system that can situationally respond to variable control algorithms such as the MPPT control, droop control, EMS power control, etc.

• 전기학회논문지
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• 제64권3호
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• pp.365-369
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• 2015

In this paper, geographic information system(GIS) for an intelligent power distribution network was implemented with location informations acquired from automatic meter reading system, where the location informations of power line communication(PLC) modems installed at customer side were collected at data concentration units(DCUs) of headend equipment via PLC and then were transmitted to front end processor server. By displaying the connection status of the power distribution network on GIS map, operation of advanced metering infrastructure(AMI) or management of power grid system could be performed intuitionally and in real time, because the configuration state of the power grid could be easily monitored. The feasibility of the proposed system was confirmed with the especially constructed laboratory-level test bed and the verification test of the system will be carried out for a real power distribution network.

• Journal of Power Electronics
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• 제17권5호
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• pp.1317-1326
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• 2017

The cascaded H-bridge (CHB) multilevel converter is a promising topology for large-scale photovoltaic (PV) systems. The output voltage over-modulation derived by the inter-module active power imbalance is one of the key issues for CHB PV systems. This paper proposed a dynamic power distribution strategy to eliminate the over-modulation in a CHB PV system by suitably redistributing the reactive power among the inverter modules of the CHB PV system. The proposed strategy can effectively extend the operating region of the CHB PV system with a simple control algorithm and easy implementation. Simulation and experimental results carried out on a seven-level CHB grid-connected PV system are shown to validate the proposed strategy.

• 조명전기설비학회논문지
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• 제21권3호
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• pp.117-124
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• 2007

요즈음과 같은 고유가 시대에 대두되고 있는 분야인 에너지 절감과 관련하여, 본 논문에서는 대단위 전력 수용가 내부의 저압배전 시스템을 특고압으로 변경할 때의 전기에너지의 손실절감에 대해 논하였다. 현재 대수용가에서는 특고압을 수전하여 저압으로 강압하여 각 부하에 전압선로로 전력을 공급하는데, 그 대신에 본 논문에서는 수전한 특고압을 수용가내의 개별 부하 근방까지 직접 가져오고 여기서 저압으로 변환하여 짧은 거리에 위치한 부하들에 전력을 공급할 때 소요되는 대략적인 설비비, 공사비의 증가금액과 선로의 전력손실 감소에 의한 절감 금액을 계산하였다. 또한 초기투자비의 회수 기간을 산정함으로 특고압 배전시스템의 경제성에 대하여 간략히 평가하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.231-233
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• 2001

Nowadays, small scale DGS(Distributed Generation System), as a wind power generation or photovoltaic generation, becomes to be introduced into the power distribution system. But in that case, it is difficult to properly maintain the terminal voltage of low voltage customers. So, it is necessary to determine the permissible operation limit of the introduced DGS for proper voltage in distribution system. In this paper computes permissible operation limit of DGS when the DGS is connected to power distribution system using fixed tap(without LDC operation). For this simulation, KEPCO distribution system is used.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.199-201
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• 2004

KEPCO, has been made a lot of efforts for computerization for distribution planning system since 1980's, And as a results, DISPLAN (Distribution PLANning System) for systematic and effective planning was developed in 2003 and is being used for feeder and substation planning of KEPCO branch office. In this paper the distribution load forecasting algorithm in DISPLAN is represented and the application was showed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1438-1440
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• 2005

A power control and distribution unit(PCDU) plays roles of protection of battery against overcharge by active control of solar array generated power, distribution of unregulated electrical power via controlled outlets to bus and instrument units, distribution of regulated electrical power to selected bus and instrument units, and provision of status monitoring and telecommand interface allowing the system and ground operate the power system, evaluate its performance and initiate appropriate countermeasures in case of abnormal conditions. In this work, we perform the preliminary design of a PCDU scheme for the small LEO Satellite applications. The main constitutes of the PCDU are the battery interface module, the auxiliary supply modules, solar array regulators with maximum power point tracking(MPPT) technology, heater power distribution modules, internal converter modules for regulated bus voltage generation. and instrument power distribution modules.

• 조명전기설비학회논문지
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• 제29권2호
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• pp.47-53
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• 2015

The study concerning about the grid connection of the large-capacity energy storage system(ESS) is increasing. However, the transient study such as lightning or switching surge necessarily occurred at power system with ESS has been hardly performed. Therefore, this paper performs the analysis of lightning surge in distribution system with ESS using electromagnetic transient program(EMTP). The battery model in Matlab/Simulink is modeled by EMTP, which is the specialized software for power system transient study. Also, the bi-directional power electronics for interconnection of the battery and distribution system are modeled by EMTP. When the lightning is occurred at interconnection point of ESS, this paper simulates the existence of ESS and operation conditions of ESS and analyzes the surge in distribution system and ESS according to the various conditions.