• 전기학회논문지
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• 제57권5호
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• pp.755-760
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• 2008

The increase of fault current due to larger power demand has caused the capacity of power machines in grid to increase. To protect the power system effectively from the larger fault current, several countermeasures have been proposed. Among them, the superconducting fault current limiter (SFCL) has been expected as one of the most effective solutions. Therefore, to introduce SFCL into power distribution system, the analysis on protection in power distribution system with SFCL is essential. In this paper, the problems of the protective coordination in power distribution system with SFCL were described.

• 전기학회논문지
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• 제61권9호
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• pp.1226-1231
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• 2012

The demand for electrical power has been significantly increased to satisfy the customers. As a result, a power distribution system have been advanced by power system's interconnection, installation of distributed generator(DG) and so on. The improvable power distribution system included the problem of increasable fault current. Superconducting fault current limiter (SFCL) is one of the solutions to limit a fault current. Therefore, to solve the problem of fault current by SFCL, simulation was progressed and the simulation used a PSCAD/EMTDC.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권2호
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• pp.73-73
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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.

• 대한전기학회논문지
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• 제39권12호
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• pp.1239-1245
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• 1990

With the rapid growth of power system capacity, fault current levels approach the maximum capacity of circuit breakers. In this paper, a superconducting current limiter (SCL) is proposed to reduce the fault current to an appropriate level. Superconductor for SCL has been examined and design criterion of each triggering method has been shown. Thin film SCL has been fabricated and switching characteristics are shown, where thermal and current triggering methods are adopted. Experimental result shows that fault current is reduced to one-half.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2003년도 학술대회 논문집
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• pp.182-185
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• 2003

Temperature distribution and cooling load in binary current lead are analized, occurring fault current at DC Reactor type superconductor fault current limiter. It is assumed that Normal operating current is 300 A and fault current is 3000 A. Unsteady-state temperature distribution and cooling load of brass current lead optimized for 300 A and 1000 A are calculated by numerical method with TDMA. In the result of calculation, temperature increase in the brass current lead optimized for 300 A is higher than that in the brass current lead optimized for 1000 A, but the temperature increase in the brass current lead optimized for 300 A is not serious. Moreover, increase of cooling load in the brass current lead optimized for 300 A is higher than that in the brass current lead optimized for 1000 A, but normal cooling load in the brass current lead optimized for 300 A is lower than that in the brass current lead optimized for 1000 A. Therefore, designing current lead in superconductor fault current limiter had better to optimize for normal operating current.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.790-792
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• 2002

The resistive type superconducting fault current limiter(SFCL) is a current limiter using the Quench mechanism of superconductors. When Quench occurs in superconductors, the resistance of superconductors increases abruptly. In order to increase SFCL capacity, current limiting elements were connected in series. If the Quench current of each element was different, voltage distribution was imbalanced. This imbalance could be removed by arrangement including series and parallel connection of elements. Based on this result, an SFCL of 1.8kV/50A was designed and experimented, expecially, in terms of increasing the voltage rating.

• 한국초전도ㆍ저온공학회논문지
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• 제5권1호
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• pp.60-65
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• 2003

An effective modeling and simulation scheme of a resistive type Superconducting fault Current Limiter (SFCL) using PSCAD/EMTDC is proposed in this paper. In case of High Temperature Superconducting (HTS) resistive type fault current limiter current limiting is implemented by the ultra-fast transition characteristics from the superconducting (non-resistive) state to the normal (resistive) state by overstepping the critical current density. The states can generally be divided into three sub-states: the superconducting state the quench state and the recovery state respectively. In order to provide alternative application schemes of a resistive type SFCL, an effective modeling and simulation method of the SFCL is necessary. For that purpose, in this study, an actual experiment based component model is developed and applied for the simulation of the real resistive type SFCL using PSCAD/EMTDC. The proposed simulation scheme can be implemented to the grid system readily under various system conditions including sort of faults and the system capacity as well. The simulation results demonstrate the effectiveness of the proposed model and simulation scheme.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 추계학술대회 논문집 전력기술부문
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• pp.154-155
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• 2007

Increase of fault current due to larger power demand has increased the possibility of the breakdown of the power system. To protect the power system effectively from the larger fault current, several countermeasures have been proposed. Among them, the superconducting fault current limiter (SFCL) has been expected as one of the most effective solutions. In this paper, the fault current limiter, which consists of a ideal switch as a trigger part and the limiter as the limiting part, has been applied into the distribution system. From the analysis for the fault current limiting operation of SFCL, the inserting resistance's magnitude has been confirmed to affect OCR trip time in a short-circuit of distribution system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.339-342
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• 2001

In this paper, the characteristics of the shielded inductive superconducting fault current limiter(FCL) were simulated and analyzed to search for the parameter to determine FCL operation, Fault current limiting operation can be executed as resistive or inductive type, which is determined by iron-core radius and the number of the primary coil turns. It was considered through this paper that the operation of each was compared and examined about the merit of each mode.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 B
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• pp.1368-1370
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• 2005

Satellite is operated only with internal battery when separated from rocket. Internal battery is charged only from SAR(solar Array Regulator), solar cell. So battery will be exhausted and purpose of satellite will be failed if load module is out of order or short. This paper proposed real time current limiter which operated by telemetry of outer processor. This current limiter operates by control signal simultaneously cuts off over current by self over current sensing circuit. So it can reduce waste of battery energy and over load of outer processor.