• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.96-100
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• 2001

We have measured the space charge distribution and PD patterns simultaneously in XLPE under AC voltages by modified PEA method in order to investigate the effect of space charge on PD patterns in XLPE with air-gap. From the experimental results, we found that the dynamic space charge accumulated on the surface of XLPE due to the PD dominantly affects the PD pattern in the dielectric-barrier structure and governs the voltage across the air-gap. Moreover, the space charge formed by applying DC voltage still remained after applying AC voltage, which means that the space charge formed during DC strength test is likely to be fatal to the long-time AC insulating characteristics of HV equipments. On the other hand, the PD patterns was much influenced by the pre-formed space charge by DC application. Therefore, it is possible to detect the effects of space charge by monitoring the infinitesimal change of PD patterns before and after DC strength.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2008년도 추계학술대회 논문집
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• pp.319-322
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• 2008

This paper introduces experimental investigates of an accident pattern for the distributing XLPE cable terminations considering PL law environment. The influence of defects such as thickness and length decrease of XLPE, the impurity on XLPE and the gap between stress-con of housing and semi-conductor on insulating properties of the termination have been studied. The thickness and length decrease of XLPE decrease ac breakdown strengths. Dielectric breakdown traces of XLPE that is damaged by knife displayed other shape. The gap of between housing and semiconductor deteriorates dielectric strength of XLPE seriously.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.142-145
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• 2004

In this paper, we researched the dielectric properties and voltage dependence on slice XLPE sheet from 22[kV] and 154[kV] power cable. studied effect for impurities and water for semiconductive shied through a dielectric properties experiment to estimate performance of insulating material in power cable. Capacitance and $tan{\delta}$ of 22[kV], 154[kV] were 52/42 pF and $7.4{\times}10^{-4}$, $2.1510^{-4}$, respectively. In these results, the trend was increased with the increase of temperature. The $tan{\delta}$ of XLPE/semiconductive layer and XLPE/water/semiconductive layer were increased as compared with that of XLPE. dielectric properties reliability of $tan{\delta}$ was small.

• 한국인터넷방송통신학회논문지
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• 제16권5호
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• pp.185-190
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• 2016

국내 발전소에서 운전 중인 XLPE 케이블(또는 CV케이블)은 많은 경우 포설된 지 40년에 이르고 있다. 설치 후 운전 상태에 있는 대부분의 CV 케이블은 6~8년의 기간이 경과하면 열화가 발생하기 시작하고, 근래에 포설한 케이블이라 할지라도 사고가 발생할 수가 있으며, 사고 발생으로 인하여 막대한 손실을 초래하게 된다. 사고를 미연에 방지하기 위하여 케이블의 동작상태를 정기적으로 감시 확인하여야 한다. 우리는 케이블의 사고를 체계적으로 감시 및 예방하기 위한 목적으로 측정 시스템을 개발하였다. 이 장비는 수 년 동안 충남 태안에 소재한 한국서부발전주식회사(Korean Western Power Co. Ltd.)에서 케이블의 동작 상태를 감시하고 있다. 이 논문에서 시스템의 기능 및 동작 원리를 소개하고, 터빈 발전기 부하용 XLPE 고압케이블의 절연층 절연상태와 습도의 상간관계를 제시한다.

• 한국화재조사학회학술대회
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• 한국화재조사학회 2011년도 제20회 추계학술대회
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• pp.63-79
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• 2010

345 kV 케이블의 종단접속부에서는 다수의 아크흔적이 발견된다. 재료분석에 의하면 케이블은 양호한 것으로 판정된다. 제조 및 설계상의 문제점은 없는 것으로 판단된다. 시공상의 결함요인 중 절연유 레벨이 낮은 것으로 추정되었다. XLPE에서는 다수의 Arc trace가 나타난 것을 확인하였다. 그러나 Soots mark가 없고, Yellow band 확인되지 않았으며, 방사형의 spider leg와 연결되지 않은 아크흔적이 없다. 이견사항으로는 XLPE의 내부에 보이드, 이물질 또는 돌기로 의심되는 것은 발견되지 않았다. 따라서 XLPE에서 이물질의 부착에 의한 절연파괴인 것으로 판단된다.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권5호
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• pp.213-221
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• 2002

In order to improve the reliability of XLPE cables, it is necessary to find the useful diagnostic parameter according to long term aging. This paper described the change of partial discharge(PD) phase Properties of XLPE cable insulation with branch type electrical tree degradation. for long term aging. To understand the PD Properties with $\phi$ -q-n distributed shape of XLPE insulation, specimens were prepared by 22.9㎸ distribution cable and made in a type of block(16${\times}$16${\times}$3[mm]). Ogura needles having tip radius of l0${\mu}{\textrm}{m}$ were inserted into each block pieces. The measuring system was consisted of PD detector, digitizer for digital conversion, VXI system for signal processing. The PD properties of the specimens were measured from initiation of tree to breakdown and their characteristics were analyzed. We analyzed the relationship between electrical properties(PD Quantity, PD initiation angle, PD extinction angle, PD occurrence angle : (PD extinction angle - PD initiation angle)) and the normalized aging rate. We found PD parameter, PD initiation angle and occurrence angle, which are a useful diagnostic parameter in estimating the branch type electrical tree for XLPE insulation condition.

• 조명전기설비학회논문지
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• 제18권5호
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• pp.90-95
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• 2004

본 논문은 XLPE(cross-linked polyethylene insulated power Cables)을 절연물로 사용하는 22.9[kV]용 전력케이블에 외부 손상에 의해 발생되는 부분 방전을 모의하였으며, 절연 진단방법 중 하나인 UHF법을 이용하여 부분 방전시 공간으로 전파되는 방사전자파을 EMI, EMC 측정용 BiconiLog 안테나(EMCO 3142)와 스펙트럼 아날라이저를 이용해 측정하는 UHF법을 이용하였다. 본 연구 결과 방전진전과정의 평가가 가능함을 확인하였다.

• 전기학회논문지
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• 제59권9호
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• pp.1644-1651
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• 2010

VLF $tan{\delta}$ diagnosis technology is introduced in IEEE Std 400 and proposed as evaluation criterion in an effective way of detecting water tree which mainly causes the failure of XLPE insulated cables. In order to inspect the accuracy of the VLF $tan{\delta}$ method for XLPE insulated power cables in Korean distribution system, diagnosis for 41 cables which were being serviced in the fields has been carried out and they were removed for AC breakdown voltage test after. Regarding the 41 cables, it was hard to confirm any relation between the VLF $tan{\delta}$ values and AC breakdown voltages and also water tree in the insulation was not detected. However, the other cables were failed several days after the diagnosis of the 41 cables. Water trees were found and their VLF $tan{\delta}$ values were also much higher than the criterion of IEEE standard. It has been ascertained that we need to change the IEEE criteria in order to improve the accuracy of detecting water trees by additional analyzing of field examples of failure and case studies from overseas countries and therefore amended VLF $tan{\delta}$ test voltage and evaluation criteria have been proposed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1393_1395
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• 2009

지중송전라인에서 전압등급의 상승은 선로손실을 줄이면서 밀집된 전력수요에 대응하거나 특별히 고전압 수요를 맞추기 위한 것으로 이것은 XLPE Cable의 제조기술이 향상되면서 지속적으로 진행되어온 초고압송전계통의 일반적 추세이다. 이러한 경향으로 국내에서는 지중송전선로로서 최고전압인 345kV가 시공되어 운전중에 있으며 해외에서는 220kV~275kV급을 넘어서 400kV급 초고압케이블라인의 수요가 증가하고 있는데, 이러한 지중송전라인의 초고압화는 높은 신뢰성이 함께 요구되며 특히 접속재 분야에서 매우 높은 신뢰성이 요구된다. 당사는 UAE 400kV AL TAWEELAH Project에 400kV XLPE 1Cx630SQ 광복합 초고압송전라인을 준공하였는데 본고에서는 여기에 적용된 400kV XLPE 1Cx630SQ 광복합 케이블 부속재의 신뢰성을 높이기 위한 설계방법, 시험 및 시공에 대하여 요약하였다.

• 전기학회논문지
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• 제67권1호
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• pp.75-81
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• 2018

In this study, the simulation of partial discharge pulse waveform have been performed for the typical joints such as EBA and PMJ in the HV underground transmission XLPE cable system in order to improve the understanding of partial discharge pulse waveform and the on-site measurement accuracy of partial discharges. FDTD simulation technique was adopted for the simulation and has been shown to be suitable for partial discharge simulation of power cables in terms of pulse propagation characteristics and waveform formation. The simulation results for the EBA showed that the second not-so-large opposite polarity peak appeared after the first negative polarity peak and the measurement sensitivity was the highest near the bottom of the EBA copper box. In the analysis results for PMJ, the magnitude of the second opposite polarity peak was large enough to compare with the first peak, and the measurement sensitivity at the end of the PMJ copper box was the highest. These simulation results show considerable similarity with the on-site measurement, and it would be very useful for the partial discharge measurement of HV XLPE cable systems.