• 한국인터넷방송통신학회논문지
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• 제15권3호
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• pp.175-180
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• 2015

산업화의 추세에 따라 수요가 급증하고 있는 고전력을 생산하기 위하여 시설장비 및 부하의 대용량화가 수반되고 있다. 전기설비의 규모는 점차 복잡해 지고, 대규모화 됨으로써 고도 정보화 사회로의 발전에 크게 기여하고 있다. 그러나, 발전 설비에서 불의의 사고가 발생하여 전기의 생산이 중단된다면, 전기에 의존하여 작동 중인 수 많은 장비가 지장을 받게 되고, 산업사회에 막대한 경제적 손실 및 장애를 초래하게 된다. 사고가 발생한 발전설비를 복구하기 위해서는 많은 시간과 비용이 소요되어 국가 산업 활동에 막대한 경제적 피해를 끼치게 된다. 사고를 미연에 방지하기 위하여 케이블의 동작 상태를 정기적으로 감시 확인하여야 하며, 우리는 절연 저항를 측정하기 위한 장비를 개발하여 (주)서부발전의 현장에 설치하여 운용 중인 바, 장비의 설치로 인한 지락 전류의 변동이 없으므로, 정확한 측정 결과를 확인할 수가 있었다. 이를 체계적 응용하여 열화 상태를 구체화하여 구현할 수 있는 사전 예방감시 기술을 연구 중에 있다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.101-105
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• 2001

고압용 가교 Polyethylene 절연 케이블의 도체와 절연체 사이, 절연체와 외부 차폐층 사이에는 계면에서의 부분방전을 방지하고 전기적 스트레스를 완화할 목적으로 반도전층이 설계되어 있다. 이 반도전층의 성질은 케이블의 품질과 신뢰성에 매우 중요한 관련이 있다. 일반적으로 반도전층은 압출 성형하는데 Base Polymer에 다량의 카본블랙을 혼합하여 도전화 한다. 절연층과 반도전층간 계면의 평활도는 전력 케이블의 수명과 깊은 관계가 있는데 만약 평활도가 좋지 않으면 전기적 Stress 가 증가하여 전선 수명이 짧아진다. 계면 평활도를 나쁘게 하는 주 요인은 계면의 Void, 반도전층의 돌기와 이물, 탄화물 등이다. 반도전 Compound 제조에 있어서 Carbon Black의 선택과 분산성은 전선수명을 결정하는 중요한 요소이다.

• 센서학회지
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• 제30권2호
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• pp.105-108
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• 2021

Detection and localization of partial discharge are considered critical techniques for estimating the lifetimes of power cables. High-frequency current transformers (HFCTs) are commonly used for the detection of partial discharge in high-voltage alternating current (HVAC) power cables; however, their applicability is compromised by the limitations of the installation locations. HFCTs are typically installed in cable terminals or insulation joint boxes because HVACs induce strong time-varying magnetic fields around the cables, saturating the ferromagnetic materials in the HFCTs. Therefore, partial discharges near the installation locations can be detected. In this study, the feasibility of partial discharge detection using a HFCT was investigated for high-voltage direct current (HVDC) cables. We demonstrated that the HFCT could be installed at any location in the HVDC power cable to monitor partial discharge along the entire cable length. Furthermore, we showed that the HFCT could detect the location of partial discharge with high accuracy.

• 한국초전도ㆍ저온공학회논문지
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• 제5권1호
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• pp.133-135
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• 2003

Cryogenic systems are requirement for the operation of HTS power cables. In general, HTS power cables require temperature below 77K, a temperature that can be achieved from the liquid nitrogen at latm or sub-cooled LN2 above latm. HTS power cable needs sufficient refrigeration to overcome its low temperature heat loading. This loading typically cones in two forms : (1) heat leaks from the surroundings and (2) internal heat generation. This paper explains the cooling test system of 10m HTS power cable. This system is composed of storage dewar, auto fill system, core cryostat and cold-box. Storage dewar is a LN2 storage tank and auto fill system is a LN2 supply device to the sub-cooler, Core cryostat is a LN2 flow line. Cold box is a control unit of temperature and flow rate. It is composed of control valve, flow meter, sub-cooler and circulation pump, etc..

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.300-301
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• 2006

Korean power system has some problems like as curtailing investment and the NIMBY (Not In My Back Yard) phenomena, because of power demand concentration in downtown area. In this time, superconducting power devices rise as a very attractive solution. This study proposes a basic concept of superconductivity power system with bulk capacity, and identifies the items for technical and economic analysis. The proposed system consists of superconducting cables/transformers/FCLs(fault current limiter). The basic concept is to replace 154kV conventional cables with 22.9kV superconducting cables and to convert a 154kV substation into a 22.9kV switching station in downtown area.

• 대한전기학회논문지:전력기술부문A
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• 제55권12호
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• pp.522-528
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• 2006

Korean power system has some problems like as curtailing investment and the NIMBY (Not In My Back Yard) phenomena, because of power demand concentration in downtown area. In this time, superconducting power devices rise as a very attractive solution. This study proposes a basic concept of superconductivity power system with distributed switching station, and identifies the items for technical and economic analysis. The proposed system consists of superconducting cables/ transformers/FCLs(fault current limiters). The basic concept is to replace 154kV conventional cables with 22.9kV superconducting cables and to convert a 154kV substation into 22.9kV distributed switching stations in downtown area.

• Journal of Electrical Engineering and Technology
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• 제9권2호
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• pp.628-634
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• 2014

This paper investigates the transient characteristics of grounding systems used in under-ground distribution power cables. Recently, two kinds of grounding system are used for underground distribution cables in Korea. The first one is conventional multi-point grounding system, the other is newly proposed non-bundled common grounding system. The non-bundled common grounding system has an advantage the decreasing the power loss due to decrease of the shield circulation current. In this paper, the lightning overvoltage induced in neutral wire (in case of non-bundled common grounding system, overvoltage between opened neural wires and grounding in each phase) of these two kinds of grounding systems are estimated and compared by field tests and EMTP simulations. The EMTP simulation methods are firstly verified by comparison of measurement and simulation. Finally, the insulation level against lightning is expected by EMTP simulation results using verified model.

• 한국인터넷방송통신학회논문지
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• 제17권3호
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• pp.189-195
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• 2017

발전소의 발전기에서 생산된 전기를 외부 단자로 공급하기 위하여 유일하게 사용되는 수단은 6 kV CV 단심 cable이다. 발전소에서 발생하는 여러 종류의 사고들 중에서 cable의 열화로 인한 화재 사고는 막대한 사회 경제적 손실을 초래한다. 설계부터 시공 및 관리를 더욱 철저히 해야 한다. 설치환경 및 사용 조건 부하량 등에 따라 차이가 있겠지만, 증설과정, 부적절한 설계 등으로 인하여 cable의 단면적이 부족할 경우가 발생하며, 운전 전류에 의하여 초과된 허용온도는 cable의 열화 상태를 초래한다. 우리는 cable의 사고를 체계적으로 감시 및 예방하기 위한 측정 장비를 개발, 한국서부발전 주식회사(Korea Western Power Co., Ltd.)에 설치하여 활선 cable을 진단하였다. 이 논문에서 우리는 cable이 설치되어 있는 주위환경 특히, 주위 온도에 따라 변동하는 cable의 피복표면의 온도를 측정하고 이에 따른 부하 전류를 검토한 결과를 제시한다. 실제 예로서 주위 온도가 $40^{\circ}C{\sim}10^{\circ}C$의 경우에 피복의 표면 온도와 부하전류의 특성을 연구한 결과를 제시한다.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.295-297
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• 2003

Cryogenic systems is requirement for the operation of HTS power cables. In general, HTS power cables require temperature below 77K, a temperature that can be achieved from the liquid nitrogen or sub-cooled LN2. HTS power cable is needed for sufficient refrigeration to overcome its low temperature heat loading. This loading typically comes in two forms : (1) heat leaks from the surroundings and (2) internal heat generation. This paper is a explanation for the cooling test of 10m HTS power cable.

• 한국의류산업학회지
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• 제20권5호
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• pp.616-620
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• 2018

Recently, many researches have been conducted to improve the performance and wearability of smart wearables. In this study, we designed and fabricated the signal and power transmission textile cables for smart wearables which have excellent wearability, durability and reliability. For the signal transmission textile cables, conductive yarns for the signal line and the ground line were developed. Three types of signal transmission textile cables have been developed using the conductive yarns. Linear density, tensile properties, electrical resistance and RF characteristics were tested to characterize the physical and electrical properties of three signal transmission textile cables. The conductive yarns have the very low resistance of $0.05{\Omega}/cm$ and showed excellent uniformity of electric resistance. Therefore, the electrical resistance of the signal transmission fiber cable can be reduced by increasing the number of conductive yarns used in signal and ground lines. However, the radio frequency (RF) characteristics of the signal transmission textile cables were better as the number of strands of the conductive yarns used was smaller. This is because the smaller the number of strands of conductive yarn used in signal transmission textile cables, the narrower and more parallel the distance between the signal line and the ground line. It is expected that the signal and power transmission textile cable for signal and power transmission will be utilized in smart wearable products.