• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.648_649
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• 2009

직류내전압시험기는 접속재 등의 절연 성능을 평가하는 시험 설비로, 설비의 측정시스템은 성능평가를 주기적으로 실시하여 시험 신뢰성의 유지하여야 한다. 본 논문에서는 직류내전압시험기의 측정시스템을 교정용 표준기를 사용하여 비교 측정을 실시하고, 그 결과를 시험시 반영하고자 한다.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.318-319
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• 2008

국내 지중배전선로에 XLPE 절연체를 사용한 전력케이블이 1980년대 중후반부터 사용되기 시작하여 20년 이상 사용경험이 축적되고 있다. 현재 국내는 전기설비기술기준에 의하여 직류내전압시험을 사용하여 준공시험을 수행하고 있다. 그러나 최근 20여년의 국제적 연구결과는 직류내전압시험이 XLPE 절연체의 결함을 발견하지 못하며 절연체 내에 장기 공간전하를 형성함으로써 케이블의 수명을 단축하는 역효과가 발생한다고 보고되고 있다. 2000년대에 XLPE 절연체를 사용한 전력케이블의 준공시험으로 초저주파(VLF) 내전압시험이 CENELEC과 IEEE 규격으로 제정되었다. 국내에도 전력케이블의 준공시험으로 초저주파 내전압시험을 도입하여 적용하는 것이 적절하며, 초저주파전압을 이용한 열화진단기술을 적용하는 것이 XLPE 절연 케이블의 고장예방에 효과적일 것으로 기대된다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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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

• Fire Science and Engineering
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• v.28 no.4
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• pp.21-28
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• 2014

This study obtained the following results by analyzing the standards related to a $1{\phi}$ 2W MCCB and evaluating its heat resistance characteristics. Since KS C 8321 corresponds to IEC 60947-2 standards, most of the related regulations are similar. The NFPA, which presents the user oriented safety regulations, contains no details about tests or inspections, etc., but it does specify in detail the regulations directly related to safety. It can be seen that KS C 8321 classifies in detail the items about tests and inspections. However, IEC 60947-2 and IEEE C37.51 simplified the test and inspection items or omitted some of them. When applying thermal stress to an MCCB for 6 hours at $180^{\circ}C$ using a heat resistant experimental device, it was found that the actuator lever was transformed and moved in the tripped state. In addition, most of the fixing hanger was melted down, losing their function. When applying thermal stress to the MCCB at $90^{\circ}C$, it showed nothing peculiar, but the fixing hanger was partly deformed at $105^{\circ}C$ and $120^{\circ}C$. It was found that the fixing hanger was deformed and the name plate was discolored at $150^{\circ}C$. It can be seen from the analysis of the internals of the MCCB that the trip bar has been melted away and that the up and down operator has moved up. The experiment performed by applying a withstanding voltage of 6 kV for 60 s showed that all items remained intact. In addition, the evaluation of the insulation performance performed by applying DC 500 V using an insulation-resistance tester showed good insulation performance.

• Fire Science and Engineering
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• v.30 no.4
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• pp.121-127
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• 2016

This study analyzed the structural and electrical characteristics of an iron fittings type Corrugated Stainless Steel Tubing (CSST) damaged by the Primary Current Injection Test System (PCITS). CSST consists of cladding, tube, nuts, clamp ring, flare cap, socket, and ball valve. For an evaluation of the dielectric withstand voltage, the area between the live part and non-live part of the CCST shall withstand a voltage of 220 V AC for one minute. For an evaluation of the insulation performance by 500 V DC, it is required that the insulation exceed more than $1M{\Omega}$ before the temperature rise test, $0.3M{\Omega}$ after the test. Although the average resistance of the product was $11.5m{\Omega}$, that of the product damaged at a current of 130 A by the PCITS was $11.50m{\Omega}$. Furthermore, parts of the cladding were melted and black smoke appeared when a current of 130 A applied for 10 s. After 60 s, most parts were heated and turned red. At 120 s, the parts that turned red had widened. Although it did not form a normal distribution because the P value was 0.019 with a confidential interval of 95%, it revealed outstanding characteristics with an AD (Anderson-Darling) value of 0.896 and a standard deviation of 0.5573.