• Proceedings of the KIEE Conference
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• 2003.11a
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• pp.367-369
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• 2003

최근까지 낙뢰에 의한 과전압으로 인해 배전설비뿐만 아니라 수용가 설비의 피해가 적지 않게 발생하고 있다. 특히 낙뢰는 호우를 동반하는 경우가 대부분이기 때문에 수용가에 미치는 피해의 파급효과는 아주 크게 나타나고 있다. 따라서 배전급 내뢰설비의 시설효과를 실제 배전계통상에서 실증적 방법으로 분석하여 최적의 운영방안을 도출함으로써 효과적인 내뢰대책을 제시할 필요성이 크다. 본 논문에서는 수용가와 직결된 주상변압기 2차측 저압선로의 내뢰설비인 저압피뢰기(Secondary Arresters, SA)의 설치효과를 특고압측 및 저압측에서의 임펄스 전압 발생을 모두 고려하여 실증시험을 수행하고, 그 시험결과를 통해 배전급 저압피뢰기의 설치효과를 분석하였다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.212-216
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• 2000

ZnO varistors for distribution surge arrester (18kV, 5kA) were developed and tested microstructure and electrical characteristics. Microstructure of ZnO varistor was consisted of ZnO grain, spinel phase and Bi-rich phase. Average grain size of ZnO varistor was $\mu\textrm{m}$ Reference voltage and lightning impulse residual voltage of ZnO varistor exhibited a good haracteristics above 5.5kV and below 11.56kV, respectively. Consequently, discharge capacity which is the most important characteristics of ZnO varistor for surge arrester exhibited excellent properties above 70kA at twice high-current impulse test. Moreover, variation rate of reference voltage and lightning impulse residual voltage showed below 5% and 2% after high-current impulse test, respectively. Leakage current and watt loss of ZnO varistor will not increase during accelerated aging test at stress condition, such as 3.213kV/$115^{\circ}C$/1000h.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.2118-2119
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• 2008

The paper introduces a new Distribution Class ground lead disconnector design that not only extends the claimable detonation range well below the 20 amps specified in industry standards, but is very durable when exposed to severe arrester durability tests. Finally, this paper shows how this next generation disconnector interacts with the connected arrester to improve the overvoltage withstand capability of the arrester assembly.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.07b
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• pp.744-746
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• 2003

A ZnO varistor with reference voltage 250V/mm was fabricated through the control of particle size in slurry and the variation of sintering conditions. It was found that to measure the flatness of the V-I characteristic curve in the small-current region and the flatness of the V-I characteristic curve in a large-current region was improved nonlinearity of the fabricated ZnO varistor. According to the IEC 60099-4 was measured the accelerated aging test and high current test of the distribution class surge varistor which is excellent in respect to the property of ZnO varistor.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1980-1981
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• 2007

This paper introduces performance characteristics of existing distribution class arrester ground lead disconnecting devices. The paper also introduces a new distribution class ground lead disconnector design that not only extends the claimable detonation range well below the 20 amps specified in industry standards, but is very durable when exposed to severe arrester durability tests. Finally, this paper shows how this next generation disconnector interacts with the connected arrester to improve the overvoltage withstand capability of the arrester assembly.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.3
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• pp.44-50
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• 2005

This paper deals with the characteristics and reduction methods of the plasma luminosity caused between the ZnO surge arrester block and metal electrodes. In this study, the impulse current generator that can generate $8/20[{\mu}s]$ impulse currents with a peak short-circuit of 10[kA] is designed and fabricated. Plasma luminosity phenomena for fine and used ZnO blocks were observed as a function of the contact states between the ZnO block and electrodes and the polarity of applied impulse voltages. As a result, discharge luminous events are produced near the contact edges between the ZnO block and metal electrodes. The discharge plasma luminosity between the ZnO surge arrester block and low potential electrode is more intensive than that between the ZnO surge arrester block and high potential electrode. Surface flashover of ZnO blocks are mainly caused by plasma generation near the edge of metal electrode. Also, plasma luminosity for the fine ZnO blocks is less than that for the used ZnO blocks. Plasma luminosity at the contact of the ZnO block and ring-type electrode is more intensive than that at the contact of ZnO block and disk electrode. It is desirable to use the disk electrode with the proper contact area to reduce the plasma luminosity caused at the contact point between the ZnO block and electrodes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.541-542
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• 2007

The paper also introduces a new Distribution Class ground lead disconnector design that not only extends the claimable detonation range well below the 20 amps specified in industry standards, but is very durable when exposed to severe arrester durability tests. Finally. this paper shows how this next generation disconnector interacts with the connected arrester to improve the overvoltage withstand capability of the arrester assembly. The interaction of the disconnector grading capacitor with the series-connected arrester metal oxide disc elements actually improves the arrester assembly temporary overvoltage withstand capability, making the design less vulnerable to TOV failures. Since the vast majority of distribution class arresters are sold domestically with ground lead disconnectors, this design improvement in the disconnector to improve detonation reliability also translates into a significantly improved distribution class arrester design.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.295-297
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• 2004

The overvoltage generated by the lightning strokes has been doing considerable damage to the distribution network as well as the consumer facility until now. Because most of the lightning strokes are accompanied by a storm, the aftermath of damage to the consumer is so serious. Therefore it is very important to survey the optimal operation plan by the field test of distribution lightning facilities. In this paper we have accomplished the field test to verify the impulse characteristic of Secondary Arrester(SA), and analyzed the effect of the SA in power distribution system.