• Proceedings of the KIEE Conference
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• summer
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• pp.409-411
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• 2004

The need for Fault Current Limiters (FCL) is associated with the continuous growth and interconnection of modem power systems and increase in dispersed generation facilities, which result in progressive increase in the short circuit capacity far beyond their original design capacity. Fault Current Limiters (FCL) clips the fault currents and reduces the electromechanical stresses on the network and the need to handle excessive fault currents. In addition, the reduction of the fault duration Provided by the limiter should increase the power transmission capability and improve the dynamic stability. This paper proposes the model of resistive type superconducting fault current limiter using EMTDC(Electromagnetic transients for DC analysis program). In order to verify the effectiveness of the SFCL, in this paper, the analysis of fault current in a transmission system through the EMTDC based simulation by using the modeled component of a resistive type SFCL is peformed and the detailed results are given.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.04b
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• pp.61-62
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• 2009

This paper describes the characteristics of lightning impulse current of ZnO block for transmission line arrester with external gap. The ageing parameters of lightning arresters ate impulse current, moisture ingress, temperature ageing and so on. Especially it is important to estimate the change of electrical characteristics by impulse current. Total energy applied to the ZnO arrester each time is $4/10{\mu}s$, 30kA and $2/20{\mu}s$, 10kA impulse current. Before and After the test, the residual voltage variation of varistors passed was below 5%. According to the test, it is thought that the ZnO arrester shows good stability with impulse current test.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.2
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• pp.179-183
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• 2008

In case of a line-to-ground fault at transmission lines, a portion of fault current will flow into the earth through the footings of the faulted tower causing electrical potential rise nearby the faulted tower footings. In this situation, any buried pipelines or structures nearby the faulted tower can be exposed to the electrical stress by earth potential rise. Although many research works has been conducted on this phenomena, there has been no clear answer of the required separation distance between tower footings and neary buried pipeline because of its dependancy on the soil electrical charactersics of the concerned area and the faulted system. In this paper, an analytical formula to calculate the requried sepeartion distance from the faulted tower has been derived.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.347-348
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• 2008

This paper presents the use of Line Surge Arresters on 154kV double circuit lines. The ouatge rate which is highly related to the tower footing resistance is showed during the last a few year. The general methods that have been adopted at lines also are introduced. Lightning performance of lines without and with line surge arrester is studied and compared. The characteristics between air-gap type and gapless type LSA also compared. Line surge arrester installation strategy is presented.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.329-330
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• 2008

제주-해남간 HVDC 변환설비는 제주 전력수요의 약 40%를 담당하는 주요 설비로, 국내에서는 처음으로 도입되어 상용 운전중인 직류송전 설비이다. 10년간의 변환설비 운전중에 크고 작은 고장이 많이 발생하였으며 PCB Card에 의한 고장은 전체 고장의 약 30%를 차지하고 있다. 본 논문에서는 해남변환소에서 사용중인 VBE (Valve Base Electronics : Thyristor 점호 제어반) Cubicle에 설치된 Databack PCB Card 점검장비 개발내용을 설명하였다. 이 장비 사용시 설비사고 및 고장의 원인을 줄일 수 있고, 카드의 연도별 이력관리를 할 수 있다. 또한 Card의 경년열화 특성을 파악하여 교체시기를 판단할 수 있고 Card 시험시간의 단축이 가능하다. 상기 이외에 점검기술에 대하여 기존 방식과 비교하고 시험기 개발 및 운영사항에 대하여 기술하고자 한다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1442-1443
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• 2015

42년간 장기사용해온 소양강 수력은 옥외 철구형 송변전 설비 노후화로 설비의 안정성과 신뢰성이 저하되었고 관련설비의 국내 제품생산 중단으로 사고발생 시 장기간의 발전정지가 우려됨에 따라 조속한 시설대체가 요구되었다. 본 논문은 소양강수력발전을 사례로 수력발전소의 전력공급 신뢰도를 확보하는 옥외변전설비 현대화사업의 주요 공정에 대하여 분석한다. 변압기 및 GIS 제조구매 설치, 154kV 송전용 철탑공사, 모선보호반 설치공사를 세가지 주요공정으로 구분하고, 각 공정별로 현장여건, 필요설비, 공정상의 이슈 해결 등 시공과 관련한 제반 사례 연구결과를 기술, 공유하고자 한다.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1104-1105
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• 2015

Recently, electric power demand increase due to the rapid industrial development. As a result, a power system has been expanded and fault currents are raised. Fault current is detriment effect on protective equipment. Superconducting fault current limiter(SFCL) is one of the solution to solve the fault current reduction. This paper analyzed operating characteristics according to applied location of SFCL in a transmission power system through the PSCAD/EMTDC simulation.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.447-454
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• 1998

This paper describes a modeling and current control techniques of Distribution static condenser (D-STATCON) for power factor compensation. The current control is based on the predictive and the space vector PWM scheme. The predictive current controlled PWM D-STATCON can maintain its performance with power factor compensation and fixed switching frequency. By using the space vector control low ripple and offset in the current and the voltage as well as fast dynamic responses are achieved with a small DC link capacitance employed.

• 전기의세계
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• v.22 no.6
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• pp.19-23
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• 1973

본고에서는 우리나라 전력공급설비의 정지율 및 신뢰도수준에 대해서 알아보았으며 내용은 다음과 같다. 1. 아직 충분한 자료분석이 되어있지 않으며, 금후의 보다 충실한 자료정비가 기대된다. 2. 발전설비는 화력단위기당의 3-6% 사고정지율을 예상하고 있으며, 수력의 경우에는 무시할 수 있을 정도이다. 3. 154kV 송전설비에 대해서는 변압기가 3대에 1대, 차단기는 14대에 1대, 단로기는 36대에 1대, 그리고 모선은 약 30회선에 1회선이 매년 사고에 의한 정지를 경험하고 있다. 5. 배전설비는 100kM에 대해서 년 17건의 사고정지와 사고지속시간 3시간이며, 수용가 평균신뢰도는 대략 99.6%(30시간 공급지장)으로 추측된다. 6. 공급신뢰도는 스스로 적정한 수준이 존재하는것이며, 무조건 높은것이 타당한 것은 아니다. 7. 공급지장비용의 평가가 금후에 해결되어야 한다.

• Proceedings of the KIEE Conference
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• 2001.07a
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• pp.491-493
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• 2001

This paper describes the effect of lightning current on combination transmission line. In the paper, an lightning current which can generate 2/80[${\mu}s$]. 20[kA] - 40[kA] waveform is modeled in ATPDraw. The lightning current invaded to the overhead power transmission line propagates to the underground power cable. The simulation was performed to analyze the effect of arrester location and overvoltage occurred in power cable.