• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1210-1212
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• 2005

High temperature superconducting(HTS) power cable system consists of HTS cable, termination and cryogenic system. And the HTS cable consists of the former, HTS phase conductor, electric insulation, HTS shield and cryostat. Taking the advantage of HTS shield, the cold dielectric has been adopted. The phase conductor and the shield have been designed to minimize the AC loss below 1W/m/phase. The former has been designed to transport the fault current of 25kA, at fault condition. This paper describes the design process of 22.9kV HTS cable considering AC losses at normal state and the stability at fault condition.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 A
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• pp.24-26
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• 2004

The growing demand for electricity has result in a corresponding increase in power generated and transmitted. As the increase in installed capacity of power system, the fault currents of 345kv system will be increased beyond the interrupting duty of the circuit breakers. The current limiting reactors are used to limit the fault current. The paper presents the result of the transient stability and voltage stability due to install 345kV current limiting reactor to suppress the fault currents.

• 한국산학기술학회논문지
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• 제15권7호
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• pp.4494-4499
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• 2014

약한 계통은 단락비가 작고 임피던스가 크므로 과도 안정도 여유도가 매우 낮다. 약한 계통에 사고가 발생하면 보호 시스템은 사고 선로를 개방함으로써 사고를 제거하는데 이것은 시스템의 안정도를 더욱 약하게 만든다. 그러므로 약한 계통의 안정도 여유를 증가시키기 위한 하나의 방법은 시스템에 추가적인 발전기를 연결하는 것이다. 본 논문에서는 약한 계통의 안정도 여유도를 증가시키기 위하여 기존의 동기발전기를 추가하는 경우와 풍력발전기의 를 추가하는 경우의 안정도 여유도를 비교한다. PSSE를 이용한 과도안정도 시뮬레이션 결과 풍력발전기가 충분한 제동력을 제공하고 안정도 여유를 증가시킴을 확인할 수 있었다. 풍력발전기를 추가할 때 안정도 여유도는 CCT 기준으로 5배까지 향상되었다.

• Journal of Electrical Engineering and Technology
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• 제11권5호
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• pp.1070-1076
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• 2016

• 한국초전도ㆍ저온공학회논문지
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• 제5권2호
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• pp.1-7
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• 2003

Nowadays, one of the serious problems in KEPCO(Korea Electric Power Co-Operation) system is the more higher fault current than the SCC(Short Circuit Capacity) of circuit breaker. There are many alternatives to reduce the increased fault current such as isolations of bus ties, enhancement of SCC of circuit breaker, applications of HVDC-BTB(High Voltage Direct Current-Back to Back) and FCL(fault current limiter). But, these alternatives have some drawbacks in viewpoints of system stability and cost. As the superconductivity technology has been developed, the HTS-FCL(High Temperature Superconductor -Fault Current Limiter) can be one of the attractive alternatives to solve the fault current problem. Under this background, this paper presents the EMTDC(Electro-Magnetic Transient Direct Current) model for resistance type HTS-FCL considering the nonlinear characteristic of final resistance value when quenching phenomena occur.

• 대한전기학회논문지:전력기술부문A
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• 제53권2호
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• pp.73-79
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• 2004

Nowadays, one of the serious problems in KEPCO system is the larger fault current than the SCC(Short Circuit Capacity) of circuit breaker. There are many alternatives to reduce the increased fault current such as isolations of bus ties, enhancement of SCC of circuit breaker, applications of HVDC-BTB(Back to Back) and FCL(fault current limiter). However, these alternatives have some drawbacks in viewpoints of system stability and cost. As the superconductivity technology has been developed, the HTS-FCL(High Temperature Superconductor-Fault Current Limiter) can be one of the attractive alternatives to solve the fault current problem. Under this background, this paper presents the EMTDC model for resistive type HTS-FCL considering the nonlinear characteristic of final resistance value when quenching Phenomena occur.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
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• pp.16-18
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• 1993

Recently, the scale of distribution system is being enlarged by increasing power demand. When system fault occurs, fault currents and damage power facilities increase, so system stability decreases. Effective prevention of system from fault extention becomes influential as a subject in distribution system operation. In this study, exact settings of relays are obtained from program for fault calculation and coordination of relays in distribution system. In order to make smooth coordination between relays even when power system conditions vary, operation time and sensitivity of relays are optimized. As a result, reliability of distribution system is increased with rapid and exact operation of relays when fault occurs.

• 한국군사과학기술학회지
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• 제12권5호
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• pp.667-675
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• 2009

Faults can be generated at electric power systems by variety of both certain and uncertain reasons, which may cause harmful effects on electrical apparatuses under operation and stability of electric power system operations, and may also lead to great confusions and inconveniences to individual livings, public works, industrial activities, services, military affairs, etc.. In some cases, intentional inductions of faults are committed for specific purposes, and it is necessary to understand the procedures of fault by some foreign materials. In this paper, compositions and operations of electric power systems, summaries of electrical fault phenomena and fault protection, and restrictions to power system operation were outlined. And the analogies on the procedure of faults from former papers were introduced, and test results that revealed the validity of those analogies were also introduced.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.321-325
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• 2005

These days, it is needed that more stability and reliability of Diesel engine. So it is essential that a systematic and comprehensive fault diagnosis analysis technology. this technology makes fault diagnosis analysis system more efficient. Expert System is required to make fault diagnosis analysis system. In this paper, fault and early diagnosis system is implemented to use Expert System development tools.

• 한국초전도ㆍ저온공학회논문지
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• 제7권2호
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• pp.35-38
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• 2005

One of the most serious problems in KEPCO system operation is higher fault current than the SCC(Short Circuit Capacity) of circuit breaker. There are many alternatives to reduce the increased fault current such as isolations of bus ties, enhancement of SCC of circuit breaker, applications of HVDC-BTB(Back to Back) and FCL(fault current limiter). But, these alternatives have some drawbacks in viewpoints of system stability and cost. As the superconductivity technology has been developed, the resistance type HTS-FCL(High Temperature Superconductor Fault Current Limiter) can be one of the most attractive alternatives to solve the fault current problem. To evaluate the accurate transient performance of resistance type HTS-FCL, it is needed that the dynamic simulation model considering transient characteristics during quenching and recovery state. Under this background, this paper presents the EMTDC model for resistance type HTS-FCL considering the nonlinear characteristic of final resistance value when quenching and recovery phenomena by fault current injection and clearing occurs.