• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기물성,응용부문
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• pp.14-15
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• 2006

제조공정상에서 발생하는 공정 변수에 의한 제품의 수준별 제품에 대하여 인가 전압별 절연저항 측정 및 내전압 측정 결과 내전압이 낮은 제품군에서 절연저항이 낮게 나타났으며 산포도 크게 나타남을 확인 할 수 있었다. PCT 시험 후의 유전 특성은 경우 용량의 변화율은 상승한 반면 제품군에 따른 용량 변화율의 크기는 작은 반면에 유전손실의 경우 PCT 실험후 변화율이 크게 나왔으며 이와같은 결과는 신뢰성 측면에서 취약할 수 있음을 보여주고 있다.

• Transactions on Electrical and Electronic Materials
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• 제8권4호
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• pp.153-156
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• 2007

Structural and electrical properties of the fully crystallized-bismuth magnesium niobate ($Bi_2Mg_{2/3}Nb_{4/3}O_7$, BMN) films with 15 mol% excess bismuth deposited on Pt bottom electrode by pulsed laser deposition are characterized for various deposition temperatures. The BMN films were crystallized with a monoclinic structure from $300^{\circ}C$ and the surface roughness slightly decreases with increasing deposition temperature. The capacitance density of the films increases with increasing deposition temperature and especially, films deposited at $400^{\circ}C$ exhibit a capacitance density of approximately $620nF/cm^2$. The crystallized BMN films with approximately 170 nm thickness exhibit breakdown strength above 600 kV/cm (${\leq}10V$) irrespective of deposition temperature and a leakage current density of approximately $2{\times}10^{-8}A/cm^2$ at 590kV/cm (at 10 V).

• 한국초전도ㆍ저온공학회논문지
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• 제14권1호
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• pp.20-24
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• 2012

This paper proposes an insulation coordination and surge arrester design for superconducting power system with SFCL(Superconducting Fault Current Limiter) in Icheon substation. In the aspect of the economic analysis, since the superconducting devices are very expensive, the insulation coordination to prevent the dielectric breakdown caused by the lightning surge should be considered carefully. In this paper, the insulation coordination for real grid including SFCL and the design of the protection devices against lightning surge is verified using PSCAD/EM TDC.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.613-616
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• 1999

Polyehtylene[PE] in polymer insulation materials of used power cable have carried out in abundance of experiment and study for electrical conduction, insulation breakdown, dielectric character and so on. when apply to field for power cable to make PE, application of DC withstand test to put in practice for inspection is get to effect accumulated space charge. In this paper, to make use of Pulsed Electro-Acoustic(PEA), It is analysis to take shape space charge under AC and DC, clear up the point at issue for DC withstand test impressing

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 추계학술대회 논문집
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• pp.516-519
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• 1999

XLPE (Cross-Linked Polyethylene) which has good electric and physical characteristic is ideal material for Insulating material with force high volumetric resistance arid high dielectric constant. We study abort electric characteristics of XLPE by DCP and TMPTA content ration. DCP (Dicumylperoxide), which was used cross-linked agent contest, was changed from 1.0 to 0.5phr. TMPTA (Trimethyl-olpropane), which was used co cross-linked agent content, was changed from 0.5 to 1.5phr. Thermal analysis by DSC in order to observe tendency of Tg according to DCP and TMPTA content. Specimen 3 that content DCP 2.0phr and TMPTA 0.5phr has the highest value Breakdown strength cf specimen 3 (DCP 2.Ophr, TMPTA 1.0phr) is the highest, value and it increased in specific inductive capacity. This due to difference from cross-linked state by DCP and TMPTA content ratio.

• 대한전기학회논문지
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• 제40권12호
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• pp.1242-1251
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• 1991

This paper is to investigate the tree growth phenomena and the characteristics of $\varepsilon$' and tan$\delta$ for the effect of ultrasonic wave on polymer insulation material. The conclusions are as follows. 1) As the pressure amplitude of ultrasonic wave is larger and its irradiated time is longer, tree inception voltage and its breakdown voltage in specimen are smaller, and tree growing is faster. 2) As the irradiated quantity of ultrasonic wave is more increased, the value of tan$\delta$ is larger, but the value of $\varepsilon$' is almost constant. 3) The effect by the pressure amplitude of ultrasonic wave is greater than that by its irradiated time on the insulation characteristics of polymer material.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1997년도 추계학술대회 논문집
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• pp.480-483
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• 1997

This paper describes dielectric characteristics and discharge development mechanisms of SF$_{6}$ gas stressed by very fast transient overvoltages in inhomogeneous electric field. Predischarge phenomena of SF$_{6}$ gas in non-uniform fields are statistically investigated with positive and negative very fast trannsient overvoltages. It was confirmed that all of the predischarges of the positive and negative polarities develop in a regime of stepwise leader extension. i.e, the predischarge developments leading to breakdown against very fast transient overvoltages are similar to the non-oscillating impulse voltages.ges.

• 전기학회논문지
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• 제66권12호
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• pp.1745-1750
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• 2017

Starting from the distribution transformer, the insulation oil for the oil immersed power transformer is being used to convert the vegetable oil from the existing mineral oil. Vegetable oil is better in temperature characteristics and insulation performance, is not toxic, and has better biodegradable characteristic than that of mineral oil. In order to investigate the corona inception voltage and dieclectic charateristics of the two insulating oils, three oil immersed transformers using mineral oil and vegetable oil were made and thermal cyclic aged. In this paper, the changes in the corona discharge inception voltage, chemical and electrical properties of the two sampled insulating oils from the transformers had been studied.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.207-208
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• 2007

Epoxy resin insulators show a lot of advantages for electrical power apparatus. Because epoxy resin provide electrical and mechanical characteristic which is excellent, it is desirable to apply epoxy resin as a spacer and post insulation in Gas Insulated Switchgear (GIS). In this study, we have investigated the influence of surface electric field attached particle contaminated spacer surfaces under SF6 gas. Also, we performed analysis of electric field. As a result, when the particle was attached on spacer, we found out a surface electric field of characteristics.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.243-247
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• 2003

The effect of accelerated weathering(UV) on three type of ethylene propylene diene monomer(EPDM) composite used for higher voltage insulator were investigated by weather-emoter. For weatherability of EPDM composite, surface resistance, dielectric breakdown strength, change of contact angle, surface composition were measured according to UV accelerated weathering time. From the resort of the measurement of surface resistivity, contact angle of EPDM composite decreased and showed chalking and cracking phenomenon when UV weathweing time was for 1500 h and 2000 h. The analysis of surface atomic composition indicated that surface aluminiu(Al) content was detected due to chalking phenomenon after 1500 h of UV weathering, Oxygen content of all composite increased due to the oxidation.