• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.71-73
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• 2006

본 논문은 단상 1MVA 22.9kV/220V 케이블 변압기의 설계, 제작 및 시험 결과를 서술한다. 케이블 변압기는 유입변압기의 폭발위험성과 환경오염 가능성이 없으므로, 인구밀집지역, 지하장소등 설치장소의 제한이 없는 장점이 있다. 제작된 케이블 변압기는 22.9kV급의 XLPE 케이블 전선을 사용하여 1차 권선을 제작하였으며, 2차측 권선은 내 단락시 특성이 우수한 몰드 권선 형태로 제작하였다. 사용된 XLPE 케이블은 도체-내부반도전층-XLPE-외부반도전층으로 구성되어 있으며, 외부반도전층은 접지된 구조이다. 철심은 단상 3각 구조로써 방향성 규소강판을 사용하였으며, 냉각방식은 공기 자연냉각방식이다. 제작된 변압기의 신뢰성을 확보하기 위하여, 특성시험과 절연시험을 실시하였다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권4호
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• pp.161-165
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• 2006

In this paper, we developed HPF (high pass filter) consists of lumped LC components to decrease the noises that are detected in PD (partial discharge) measuring test, and adapted it to field test. We tested it under laboratory circumstances like the fields, and measured the phase change properties of detected signal in UHF sensor with Lemke Probe and oscilloscope (TDS-3054, Tektronix). As a result, we obtained available data showing the decrease of noises in the experiments with the developed HPF from the joint box of 22.9kV distribution line. The result can be adapted to prevent the degeneration of the XLPE power cable, and to observe and diagnosis the underground power transmission cable at the ultra-high voltage.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기설비전문위원
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• pp.97-100
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• 2004

HFPD(High Frequency Partial Discharge) measurement has been widely performed to diagnosis of cable system in the world although Korea just begin. The efficiency of measurement has been reported and proved by many researchers who are engaged in the diagnosis of high power apparatus. LG Cable has investigated the technology of diagnosis for cable system by means of PD measurement for 10 years. In this paper, PD measurement with portable device was performed to evaluate the quality of the 154kV transmission line and the 22.9kV XLPE cable line. Test results are shown that the HFPD detection technology is very attractive for the diagnosis of power cable system by high detection sensitivity at on-site.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권9호
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• pp.628-633
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• 1999

Degradation diagnosis of XLPE insulated URD cables was accomplished through out new method, which was to be analyzed by non-electrical experiments and synthesized by degradation points. To supplement this method, It was also carried out using several electrical analyses. Tan$\delta$ had commonly a different tendency by means oftemperature and frequency and also appeared higher at the outer part rather than innerpart of insulator. PD-q increased generally in proportion to the applied voltage andshowed regular patterns in relation to the thickness of insulator. Breakdown voltageswere measured and breakdown lifetimes were predicted appling for Weibull distribution function. As a result, breakdown lifetime in failure cables was shorter up to$\fraction one-third$ times than that in general cables. It was very available to estimate cable degradation using above method, but it needs further study on XLPE insulated URD cables in order to improve reliability.

• Journal of Electrical Engineering and Technology
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• 제3권4호
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• pp.559-565
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• 2008

This study designed a new type of loop antenna that is able to detect partial discharges based on microstrip line technology. In the diagnosis of power cables, partial discharge signals are generally produced at a frequency range less than 100MHz because high frequency PD signals are lost along a propagation path in such cables. The new type of loop antenna sensor has been studied using simulation software known as CST microwave studio version 5.0. In partial discharge measurement experiments, a commercial HFCT sensor was used as a reference sensor. Several experiments were made over HFCT and loop antenna sensors for detecting partial discharges on 22.9kV MV XLPE cable. In this study, we showed the loop antenna designed in this study that can be applied as a commercial HFCT sensor.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.2020-2022
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• 2000

The cross-linked polyethylene(herein after XLPE) insulated power cable emit the methane($CH_4$)gas in the course of chemical cross-linking process. The general stranded conductor easily discharge this methane gas through the gap of each stranded wires. But the special stranded conductor that filled with semi-conducting rubber compound to prevent water penetration which is applied to water proof type of cable(22.9kV CN/CV-W), disturb the methane gas emission. The pre-mold type cable joint shall be expanded gradually by emit of gas left in XLPE insulation. For example, sometimes the corona problem outbreak on a new power distribution line, resulted from the gap between the sleeve and semi-conductive layer of cable joint. If above mentioned problem especially happened on the way of operating. We have to shut down the line and try to discharge the methane gas in cable joint. In this point, we would like to explain the mechanism of methane gas & cable joint and our test result briefly. At last, we are pleased to introduce the solution for preventing reoccurrence of this problem.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.1449-1452
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• 2007

배전 케이블 부분방전 측정에서는 외부노이즈, 코로나가 동반되어 검출되고 있다. 특히, 단말부의 부분방전측정에서는 부분방전 현상이 크게 발생하여 측정될 경우 다른 상에서도 유입되어 검출되는데 코로나나 외부의 노이즈가 크게 유입될 경우 진단의 어려움이 있다. 더불어 각 상의 위상을 직접검출이 어려운 송배전 케이블의 단말에서는 유기된 신호의 상을 찾는데도 어려움을 주고 있다. 이러한 문제를 반영하여 현장 측정이 용의하도록 이동형 포터블 진단장치를 개발하였다. 3개의 HFCT 센서를 사용하여 3상을 동시 측정할 수 있도록 하였다. 전원 분압 트리거 회로와 전류 변류 트리거 회로를 사용하여 위상 분석을 병행하였다. 실선로의 배전 케이블 부분방전 진단의 효율적 수행을 위해 개발된 본 장비를 현장 적용하였으며 내장된 PRPD 분석법이 가능하였으며 S/W 노이즈 게이팅을 적용하여 다른상에서 유기되는 신호를 제거하여 진단결과의 신뢰성을 높일 수 있었다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 C
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• pp.1805-1807
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• 2004

This simulated partial discharge caused by 22.9[kV] power cable using XLPE(Peroxide Crosslinkable Polyethylene) insulation having the outside damage. Asone of the insulation diagnostic method a radiated electromagnetic waves were measured by an UHF method using a BiconiLog antenna(EMCO-3142) and a spectrum analyzer used to measure EMl, EMC. From results of this study, It was confirmed that discharge progress were possible to be estimated by the proposed method.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1505-1506
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• 2006

XLPE 절연 전력케이블의 제조과정에서 발생하는 가교부산물을 제거할 목적으로 14주기노화를 실시한다. 이 과정에서 가교부산물이 제거되는 효과도 있지만 열에 의한 구조적 결함도 생기게 되며, 이들 모두가 뇌충격파괴전압에 영향을 준다. 22.9kV 트리억제형(TR CNCV-W) 케이블에 대하여 14주기노화 전과 후의 파괴전압을 분석하였으며, 전반적으로 노화과정이 파괴전압을 감소시키는 결과를 보였으나 60 $mm^2$ 케이블은 상승효과와 감소효과가 비슷하게 작용하는 것으로 나타났다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.102-102
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• 2010

A purpose of this paper is to recognize partial discharge pattern for cable insulation. The classification of PD sources was widely studied for two decades. this research sought to use the partial discharge detection method, and to diagnose the interface of cable, which is deemed vulnerable of cable systems. A research abalyzed faults that can occur in the interface of cable joint as well as accident mechanisms, manufactured test 22.9kV CNC cable, invented artificial faults and carried out partial discharge detection experiments. As a result, various PD pattern along defect measured and distinguished.