• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.224-228
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• 1988

Extensive development work which was carried out by Gold Star Cable Co., Ltd. has led to the optimal design, manufacture and test of fully engineered cable system for 345 kV self- contained oil filled (OF) underground cable. Details of design criteria and of tests are given. development of 345kV OF cable results in sucessful operations for ultra-high voltage power transmission requirement.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1966-1968
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• 2000

Globally, oil-filled paper-insulated cables and cross-linked polyethylene-insulated cables have been mainly applied for a underground power transmission line. The oil-filled cable has the hydraulic system in which insulating oil, expanded and contracted by temperature changes, is absorbed and supplied. This system enable us to detect oil leakages from the cable. But it has some problems such as difficulty in detecting minor leakages and a relatively long period of fault detecting. And so, this paper introduce a new leakage detection system, improved from the current one.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.319-322
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• 2002

Distance relay is operated in calculating line impedance. It can be worked accurately in overhead line. However, power cables or combined transmission lines need compensation for calculated impedance because cable systems have sheaths, grounding wires and sheath voltage limiters(SVLs) Neuro-fuzzy can be viewed either as a fuzay system, a neural network or fuzzy neural network and it can estimate the location of the fault accurately. In this paper, fault section and fault location can be classified and estimated in neuro- fuzzy inference system and neural network.

• 한국정보통신학회논문지
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• 제21권8호
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• pp.1597-1603
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• 2017

지하공동구의 화재 발생 빈도는 다른 화재에 비하여 낮은 편이나 화재로 인한 피해는 경제적 손실 뿐만 아니라 사회운영 마비로 사회적 손실을 초래할 수 있다. 이에 본 논문은 지하공동구 내 설치된 누설 동축케이블을 이용하여 지하공동구의 상태감시시스템 구축에 대한 실증 시험 결과를 제시한다. 이를 위해 지하공동구에 설치된 누설 동축케이블에 삽입손실 특성이 $-6{\pm}2dB$인 유도성 커플러와 200 Mbps급 전력선 통신 모뎀을 연결하여 실증 시험한 결과, 500 m까지 IP 카메라의 송/수신을 확인하였다. 따라서 데이터 전송을 위한 통신선로의 추가 설치 없이도 지하공동구 내 설치된 누설 동축케이블을 이용하여 지하공동구에 상태감시시스템 구축이 가능할 것으로 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1646-1648
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• 1994

In the system of underground transmission line, the rate of electrical failure is very low, but, if once occuring, the failure evolves into a paralysis of the system, the time of restoration is very long, the damage from stopping of power supply is very serious, and the cost of restoration is very great. Because of these problems, you must try to protect the system and equipment from every electrical failure by contributing much carefulness to the design and operation of the underground system. This study summerizes the results of simmulation tests about the effect of installing this protection device on the insulated joint box and the terminal end box.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 A
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• pp.409-411
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• 2003

As power demand increases gradually, the call for underground transmission system increases. But it is very difficult and high in cost to construct new ducts and/or tunnels for power cables in metropolitan areas. HTS (High Temperature Superconducting) cable has the several useful characteristics such as increased power density. Therefore HTS cable can allow more power to be moved in existing ducts, which means very large economical and environmental benefits. In this paper, we carried out investigation for Application of 22kV class HTS cable in Korean utility networks. The results show that the HTS cable is applicable to replace IPB in pumping-up power plant, withdrawal line in distributed generation, withdrawal line in complex power plant, and conventional under ground cable. Finally, as the cost of HTS wire and refrigeration drops, the technical and economical potential of HTS cable is evaluated positively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 C
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• pp.1057-1059
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• 1999

Recently, increased demand of electrical energy caused additional installation of underground power cable, Industrialization of metro makes civil works difficult. So installed ducts became a key of underground power transmission, LG cable set to work development of high stress cable. LG cable stated in 1996, got a certificate of type test in 1998, and applied at domestic site in Nov. 1999. High stress cable has some merit, decrease of civil cost, reduction of work time, by reason of decrease of dia. and weight, and economical system design, so LG cable has a good merit in comparison with competitive company in domestic and foreign market.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전력기술부문
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• pp.383-386
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• 2001

Distance relay is tripped by the line impedance calculated at the relay point. Accordingly the accurate operation depends on the precise calculation of line impedance. Impedance can be accurately calculated in case of overhead line. However, in case of power cables or combined transmission lines, impedance can not be accurately calculated because cable systems have the sheath, grounding wires, and cable cover protection units (CCPUs). There are also several grounding systems in cable systems. Therefore, if there is a fault in cable system, these terms will severely be caused much error to calculation of impedance. Accordingly the proper compensation should be developed for the correct operation of the distance relay. This paper presents the distance calculating algorithm in combined transmission line with power cable using wavelet transform. In order to achieve such purpose, judgement method to discriminate the fault section in both sections was proposed using db1 coefficient summation. And also, error compensation factor was proposed for correct calculation of impedance in power cable.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.248-248
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• 2007

Demands for electricity are growing, whereas the rate of electricity infrastructure's construction declines gradually. To keep the balance of the demand and supply, the share of underground transmission line will be increased from 8.3% to 10.5% in 2020 but it will be accompanied with enormous public expenses. A great concern in high capacity transmission is on the increase so as to maximize the spacial efficiency. High Temperature Superconducting (HTS) cable is in the lime light which has the merits of environment-friendly, low transmission loss and high transmission with low voltage, but the reliability verification as a power system is yet to be solved. KEPCO completed the installation and acceptance of $3{\phi}$, 22.9kV, 1250A class HTS cable system in 2006 and the long term test is in progress. The test results focusing on long term reliability are presented in this paper.

• 한국초전도ㆍ저온공학회논문지
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• 제5권2호
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• pp.20-29
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• 2003

As power systems grow more complex and power demands increase, the need of underground transmission system is increasing gradually. But it is very difficult and high in cost to construct new ducts and/or tunnels for power cables in metropolitan areas. HTS (High Temperature Superconducting) cable can carry very high current densities with strongly reduced conductor loss and allow high power transmission at reduced voltage. Therefore HTS cable can transfer more power to be moved in existing ducts, which means very large economical and environmental benefits. A development project for a 22kV class HTS cable is ongoing at a research centers, and the cable manufacturer in Korea. In this paper, we carried out investigation for application of 22kV class HTS cable in Korean utility networks. The results show that the HTS cable is applicable to replace IPB in pumping-up power plant, withdrawal line in distributed generation, withdrawal line in complex power plant, and conventional under ground cable. Finally, as the cost of HTS wire and refrigeration drops, the technical and economical potential of HTS cable is evaluated positively.