• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2361-2363
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• 1999

The conventional SiC-type of lightning arresters in distribution systems has been replaced by ZnO-type because the ZnO-type has characteristics such as outstanding non linearity, high energy absorption capability, surge suppressing performance, and excellent response to abrupt wave. Out of the various types of lightning arrester failures, some which have been often reported could be prevented in advance. Therefore, the preventive countermeasures which can cope with the failures are strongly required. This paper summed up and analyzed the lightning arrester failures which occurred, from 1983 to 1992, in distribution systems in order to provide fundamental data, classified by year, to make countermeasures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 C
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• pp.1342-1344
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• 1997

Zinc oxide varistors which contain rare earth metal oxides have been developed. These Varistors are widely used for low voltage surge-protection devices and high voltage arresters for electric power stations. The characteristics of varistors with praseodymium oxide as a principal additive are discussed. A two-phase microstructure with an intergranular phase between the ZnO grains.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.497-499
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• 2003

This paper analyses the lightning overvoltage with earth of grounding wire and installation types of arresters in double circuits distribution systems. First, the model for analysis is selected severer case between upper line and lower line when the direct lightning surge strikes on the overhead grounding wire. The lightning overvoltage is variously calculated with earth distance between overhead grounding wires. This paper also analyses the effect of the installation distance between arrestors and the earth resistance of overhead grounding wire. From these results, authors examine the rationality of BIL that is applied in distribution system.

• 조명전기설비학회논문지
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• 제21권1호
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• pp.75-81
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• 2007

본 논문은 가스절연변전소에 설치되어 있는 피뢰설비의 감시와 진단이 가능한 전문가 시스템의 선계 및 구현에 대하여 기술하였다. 제안한 전문가 시스템은 마이크로프로세서 기반의 데이터 취득 모듈과 진단 알고리즘으로 구성되며, 피뢰기 진단에 필요한 계통전압, 누설전류성분 및 온도 등을 검출하고 분석한다. 또한 서지전류의 발생시각, 극성 및 크기를 기록할 수 있는 지능형 서지 카운터를 내장하고 있다. 측정된 모든 데이터는 IEEE 802.15.4에 규정된 저속 무선망을 통해 원격지의 컴퓨터로 전송되며, 이로 인해 고전압 대전류 환경에서도 전자계 간섭을 피할 수 있다. 전문가 시스템에서 피뢰기의 진단은 지식 베이스와 추론 엔진, 그리고 그래픽 사용자 인터페이스로 구성된 JESS(Java Expert System Shell)를 이용하여 결정한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.501-503
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• 2000

Since an arrester has been generally used at the distribution line and abroad for the protection of electrical equipments against overvoltage (or abnormal surge) taking place in or from an electrical system, a fault, especially, in the distribution line is very likely to result in the destruction of insulation of other protection devices to cause an overall paralysis of a power system, a chaos. Considering the importance of arresters, its earlier replacement than its proposed life cycle causes an economical loss, and a negligence not to replace or repair it in time gives rise to a crucial accidence. The purpose of this paper is to invent an electric leakage current detector and to solve such problems by the continuous and regular inspection of an arrester.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.48-50
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• 2004

The energization of high voltage transmission lines and transformers, that is an inevitable process in most countries as the first restorative action for wide-area blackout, may induce overvoltages such as sustained overvoltage, transient overvoltage and harmonic resonant overvoltage. And these may cause damages to power system equipments or failure of surge arresters. The harmonic resonant overvoltage originates in switching operations and nonlinear characteristics of equipments. Actually it is difficult to predict the occurrence of harmonic overvoltage, since they result from nonlinear characteristics of transformers and other equipments. This paper describes the analysis of domestic primary restorative transmission system using PSCAD/EMTDC. The harmonic resonance is verified and the solution to prevent harmonic resonance is proposed in this paper. As a result, the PSCAD/EMTBC simulation showed slightly conflictive results that had been presented by IEEE Power System Restoration Working Group report.

• 조명전기설비학회논문지
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• 제21권10호
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• pp.59-65
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• 2007

최근 유비쿼터스 센서네트워크 기술이 전력설비관리에 적용되어 오고 있다. 본 연구에서는 가공배전선로에서 전력용변압기와 피뢰기를 관리할 수 있는 유비쿼터스 센서의 설계 및 제작에 대해 기술하였다. 이 센서들은 8-[bit] 마이크로프로세서, IEEE 802.15.4기반 무선통신모듈과 주변 전자회로로 구성되어 있다. 변압기의 부하 및 서지전류 측정에는 1000[A]까지 포화되지 않고 선형성을 유지할 수 있도록 공심형 로고우스키 코일을 제작하여 적용하였다. 피뢰기를 흐르는 $50[{\mu}A]{\sim}1[mA]$의 미소누설전류를 측정하기 위하여 180[Hz]에서 $10^5$의 고투자율을 갖는 영상변류기를 사용하였으며, 피뢰기 감시모듈의 -3[dB] 주파수 대역은 12[Hz]에서 1.24[kHz]이다.