• 전기의세계
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• v.18 no.2
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• pp.21-25
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• 1969

This paper shows experimentally the characteristics of raising up the flashover voltage in supension insulators or bushing according to the theoretical results which was gotten by previous study. It was shown theoretically that, if some conducting metallic barriers are inserted into the flashover discharge path, the flashover voltage is found to be increased considerably. In order to verify this theoretical results, some basic experimental study was done, and the results was found to be more or less satisfactory except some problems which must be considered in future study.

• 전기의세계
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• v.18 no.1
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• pp.7-10
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• 1969

This paper shows theoretically the possibility of raising up the flash over voltage in suspension insulators or bushing according to the results which was gotten by previous study done by the Author. If some conducting metallic barriers are inserted into the flash over discharge path, the flash over voltage is forund to be increased condiferablly. Applying this priciple, some methods of improving flash over characteristics are discussed theoretically.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.230-233
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• 1996

In this paper, We intended to evaluate characteristics of XLPE/EPDM interface which exists in the cable joint. Because the fault was mainly occurred in this interface. We investigated breakdown characteristics of XLPE/EPDM double layered insulator as a funtion of temperature, pressure, annealing time, kinds of jointmaterial. It was shown that breakdown strength of XLPE/EPDM insulators is higher that of XLPE/XLPE or EPDM/EPDM

• Electrical & Electronic Materials
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• v.11 no.11
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• pp.17-21
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• 1998

The surface potential distribution on insulating polymers was measured by scanning of the probe of an electrostatic voltmeter. The measurements were done for two measured by scanning of the probe of an electrostatis voltmeter. The measurements were done for two cases. In the first case, it was measured on the free surface of insulating films which had been inserted between plane electodes after the removal of the upper brass disk electrode. In the second case, we measured the charging region between a circular and its opposing concentric ring electrodes after the removal of dc ramp voltage in air and nitrogen gas.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1367-1369
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• 1994

Recently composite insulators have been In the spotlight because they have many good characteristics as a outdoor insulator for high voltage. The long term properties in composite insulator depend on shed materials. Silicone rubber out of some candidates of shed material has been obtaining good credit from the long term test in field.

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.37-40
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• 2001

Aromatic polyimides는 다른 고분자 재료에 비해 고온에서의 열 안정성 및 기계적 물성, 내화학성, 전기 절연성, 난연성 등이 매우 탁월하기 때문에, 최근 들어서 고성능 구조재료, 전자재료(microelectronics devices, electrical insulators of semiconduntor packages), 내열성 접착제, 코팅제 등 그 응용 범위가 점차 확대되고 있는 추세이다. (중략)

• Journal of the Korean Chemical Society
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• v.41 no.8
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• pp.437-441
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• 1997

The acid strngth of cations, determined with ICP (Ionic Covalent Parameter): ICP=log(P)-1.38x+2.07 where P is the polarizing power and X its electronegativity expresses the competition between the covalent and ionic forces. This concept, together with electronegativity, is used to describe the properties of oxides with various electronic properties (insulators, metals, degenerate semiconductors, superconductors).

• The Journal of Information Technology
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• v.7 no.2
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• pp.69-76
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• 2004

This paper presents the results of spectral analysis about waveforms and leakage current waveforms on contaminated silicon insulators under various environment conditions.(salt fog, clean fog, rain). The larger the leakage current during 200ms, the higher the power spectrum at 60Hz. If contaminated insulators suffers from high salt density fog, the leakage current occurs with high crest value intermittently, results in the low spectrum. Analysis of leakage current data showed that this electrical activity was characterized by transient arcing behavior contaminants are deposited on the insulator surface during salt fog tests. This provides a path for the leakage current to flow along the surface of the insulator. It is important to have an indication of the pollution accumulation in order to evaluate the test performance of a particular insulator. If the drop in surface resistivity is severe enough, then the leakage current may escalate into service interrupting flashover that degrade power quality.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.1
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• pp.62-67
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• 2005

Recently, polymer insulators that are used for high voltage applications have some advantages such as light weight, small size, vandalism resistance, hydrophobicity and easy making process. During outdoor service of polymer insulators, the surface of the insulating material is frequently subjected to moisture and contamination that lead to dry band arcing. Their tracking resistance, erosion resistance, end sealing and shed design are very important because dry band arcing causes degradation of polymer surface. Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. Polymer material is also investigated it's tracking resistance by adding surface active agent in IEC 587. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination, STRI guide and thermal image camera.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.6 s.348
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• pp.18-22
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• 2006

The inspection of surface properties under n-octadecyltrichlorosilane treated $SiO_2$ film was carried out by current-voltage characteristic and the scanning electron microscope. The voltage at zero current in low electric field is the lowest at 0.3 % OTS treated $SiO_2$ film with hybrid type. $SiO_2$ films changed from inorganic to hybrid or organic properties according to the increase of OTS content. OTS treated $SiO_2$ films with hybrid properties decreased the leakage currents, and the grain size of pentacene deposited sample was also the most small at the hybrid properties. The perpendicular generation of pentacene molecular was related with the surface of insulators. The surface with hybrid properties decreased the grain size, but that with inorganic or organic properties increased the grain size.