• 조명전기설비학회논문지
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• 제24권8호
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• pp.48-54
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• 2010

교류 전기철도 시스템은 비선형 단상 부하인 차량의 부하특성으로 인해 고조파 왜곡, 무효전력 발생, 3상 불평형과 같은 전기품질 문제를 가지고 있다. 이 같은 전기품질 문제는 철도 시스템뿐만 아니라 철도와 연계된 다른 건전한 계통에도 악영향을 미치게 된다. 따라서 본 논문에서는 이와 같은 전기철도 급전시스템의 전기품질 문제를 보상하기 위해 철도용 전기품질 보상장치(RPQC; railway power quality conditioner)를 적용하고, SRF(synchronous-reference-frame) 제어를 이용한 RPQC의 제어방법을 제안한다. 제안하는 제어방법을 통해 RPQC는 고조파 왜곡, 무효전력, 부하 불평형과 같은 전기품질 문제를 순시적으로 보상할 수 있으며, 시뮬레이션을 통해 이를 검증한다. 시뮬레이션 결과는 제안한 RPQC 제어방법의 타당성을 보여주고 있다.

• 전기학회논문지P
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• 제58권4호
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• pp.579-584
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• 2009

This paper describes a power quality analysis of a photovoltaic generating systems. Prior to the power measurement, domestic and foreign codes related to the photovoltaic generating systems were briefly summarized. After constructing about 5 kW photovoltaic systems, input/output voltages and currents were measured to compare and analyze the power quality by the module type. Based on the measured values, a couple of factors such as active power, power factor, total harmonic distortion(THD) was calculated and analyzed.

• 대한전기학회논문지:전력기술부문A
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• 제55권2호
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• pp.53-58
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• 2006

This paper proposes a small low-cost power quality compensator to be installed at the electricity supply inlet of residential customer. The compensator is composed of a single-phase active power filter with a simple controller using analog electronics, which can correct the power factor and damp out the harmonics. The operation and performance of proposed compensator was verified through simulations with PSCAD/EMTDC and experimental works with hardware prototype. The proposed compensator can offer reduction of power loss and improvement of power quality to the residential customer.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.148-150
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• 2003

A meaning of power quality has changed, which affects on an environmental change of existing electricity supply markets. Today, it should take both consumers and suppliers into consideration to develop information and communication technology and to increase the use of power and electronic equipments. As a result, it is necessary to develop a system to monitor power quality and to display data. In this paper, a system, as a power quality monitoring equipment, which can use protective replays with progress of microprocessor technology and provide information in the intranet/internet circumstances using web-based architecture is described.

• Journal of Power Electronics
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• 제13권3호
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• pp.458-468
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• 2013

Large capacity reactive power compensation and harmonic control in the low-voltage grid of an enterprise, are important technical means to improve power quality and reduce power loss. In this paper, the principle of an efficient power quality controller is analyzed. Then, key application technologies of the HPQC which would influence the performances of the HPQC are studied. Based on an analysis of the harmonic shunt problem, a frequency dividing control strategy of the HPQC continuous subsystem is proposed. A parameter design method of the HPQC discrete subsystem and its installation method are also proposed to ensure the system compensation effect. HPQC systems have been designed for a copper foil plant. The effectiveness of this paper has been verified by the simulation and application results.

• 한국산학기술학회논문지
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• 제8권3호
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• pp.444-453
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• 2007

최근에 전기 아-크로의 보급과 그 운전으로 전력계통에 전압플리커 및 유효전력변동과 같은 전력품질상의 문제가 발생될 가능성이 높은 것으로 보고되고 있다. 이 문제를 해결할 수 있는 방법에는 대표적으로 무효전력보상방법이 있는데, 이것은 유효전력변동의 전력품질문제해결에는 한계가 있다. 따라서, 본 논문에서는 이의 해결책으로서 X/R 비율에 근거한 유효전력보상 개념과 그 최적앨고리즘을 제안하여 이의 타당성을 모델링과 시뮬레이션을 통하여 검증하였다.

• 조명전기설비학회논문지
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• 제19권4호
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• pp.91-97
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• 2005

산업화로 인버터, 컨버터, 스위칭 전원공급기, 모터와 같은 비선형 장치들이 늘어가고 있다. 그러나 컴퓨터와 전기장치 등과 같은 전력품질에 민감한 부하의 사용이 빠르게 확산되어 왔다. 게다가 전력품질 문제와 실시간 전력품질 모니터링은 산업과 빌딩에서 시스템의 지능제어로써 관심이 증대되고 있는 문제 중에 하나이다. 그중 하나인 전력선통신을 이용한 전력품질 모니터링 시스템은 새로운 선로가 없이도 전력품질 정보를 보내고 받을 수 있는 큰 장점을 가지고 있다. 본 논문에서는 IEEE Std. 1159의 분류에 따라 전력품질 문제를 측정하는 알고리즘의 개발과 보드를 제작하고 이를 전력선통신을 이용하여 모니터링하는 시스템을 구현하였다.

• 산업경영시스템학회지
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• 제24권63호
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• pp.89-99
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• 2001

This paper proposes assessment of quality management activities based on cost of quality. Cost of quality is considered prevention cost, appraisal cost, internal failure cost, external failure cost in this paper. This paper shows quality cost magement system in thermal power site devision according to activity analysis. Cost of quality in power industries provides a valuable method of both proving the need for improvement and giving a starting point for projects.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.164-168
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• 2005

In this paper a statcom is developed to improve the power quality in a dc traction system. The proposed statcom can be used as both inverter and active filter. As an active filter, it can compensate harmonic distortion and reactive power and as an inverter, it can recycle regenerative energy caused by decelerating trains. The simulation results are carried out by using PSCAD/EMTDC software.

• 대한전기학회논문지:전력기술부문A
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• 제53권11호
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• pp.581-588
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• 2004

Power qualify monitoring system is devoted to more concern than before, because the innovation of industrial technology needs more accurate instruments and more advanced power quality. This paper was studied on using data of the protective relay by Power Quality Monitor. This paper was proposed the wave storage condition and monitoring clauses of the protective relay as a power quality monitoring device. The protective relay will have problem to save data for PQM analysis because the protective relay memory is limited. Therefore this paper was proposed new a data compression of data got from the protective relay. This method is wave compression comparison algorithm using the DFT. The compression rate is higher than any other established method. This method can be real time storage. This algorithm is verified using the comparison among other compression rate and proved by Real Time Digital Simulator (RTDS).