• 전기학회논문지
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• 제62권1호
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• pp.143-148
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• 2013

When the fault occurs in power system, the fault-current exceeds breaking capacity of the circuit breaker. So, reliablity of the power system is decreased sharply. Superconducting fault-current limiter (SFCL) is operated without impedance in normal state. The fault-current is limited by its impedance during the fault condition. However, the SFCL has several weak points such as huge size, high-price, liquid-nitrogen operation for the real power system. In this paper, We suggested the high-speed interrupter to limit the fault-current in case of the single line-to-ground fault. In addition, we compared the high-speed interrupter with the SFCL to ensure the operation reliability. The proposed interrupter detected the fault-current through the CT, and the power was supplied by operation of the SCR control system. In this experiment, the power of high-speed interrupter was applied after the 4.8[msec] from fault instant. The on-off operation of the interrupter was started after half-cycle from the fault. The fault-current was flowed into the impedance element by the switching operation of the high-speed interrupter. So, the fault current was limited within one cycle, and then it didnt exceed the capacity of a circuit breaker. We confirmed that there was slight difference between the SFCL with high-speed interrupter in terms of limiting-time of the fault-current and switching speed of the SCR. The high-speed interrupter was considered to be more efficient than the SFCL in size, cost or reliability.

• Journal of Electrical Engineering and Technology
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• 제12권1호
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• pp.182-188
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• 2017

An arc eliminator allows a surge current bypass rapidly into the earth to facilitate the circuit breaking process and increase the stability of the load circuit. Thomson coil actuator (TCA) is a type of actuator that can function as an arc eliminator. The TCA has a simple structure and significantly rapid speed compared to the other types of actuators. In this paper, significant variables, which have a dominant effect on the performance of the TCA, are investigated in detail. Using these variables and an optimization algorithm, an optimal design strategy for the TCA is proposed in this research. The efficacy of the proposed optimal design strategy and the feasibility of the application of the designed TCA for a high power circuit breaker as the arc eliminators are validated through the experiment.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.417-422
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• 2008

The DC high speed circuit breaker used in Seoul Metro for line no.1.2 is Japan HITACHI and FUJI breaker, and for line no.3.4 is Whipp & Bourne MM74 breaker from UK. The years that each breakers made are 1973(line no.1), 1984(line no.3.4), So that equipments are superannuated. Nowday the for equipment exchanging is executing, equipment for exchanging were used the Secheron breaker from Swiss. but now the Intec breaker made in Korea is used. The RTU of supervisory control and data acquisition system have the capabilities that can observe, control and work the installation efficiently. In this paper, as summarizing the solving process of problem that happened the SCADA system when old-equipment exchange and concerned point for logical supervision and control of reservation factors and equipment, I'll provide the direction that can do receiving-process of control-equipment, progressed with the exchange of old-electronic equipment.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제50권7호
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• pp.331-337
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• 2001

With the increasing reliability of analysis schemes and the dramatically increased calculating speed, the computer simulation has become and indispensable process to predict the interruption capacity of circuit breakers. Generally, circuit breakers have to possess both the small current and large current interruption abilities and the circuit breaker designers need to evaluate its capacities to save the time and the expense. The analysis of small current and the large current interruption performances have been considered separately because the phenomena occurring in a interrupter are quite different. To analyze the dielectric recovery after large current interruption many physical phenomena such as heat transfer, convection and arc radiation, the nozzle ablation, the ionization of high temperature SF(sub)6 gas, the electric and themagnetic forces and so forth mush be considered. However, in the analysis of small current interruption performance only the cold gas flow analysis needs to be carried out because the capacitive current is to small that the influence from the current can be neglected. In this paper, an empirical equation which is obtained from a series of tests to estimate the dielectric recovery strength has been applied to a real circuit breaker. The results of analysis have been compared with the test results and the reliability has been investigated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.524-526
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• 1997

High speed DC circuit breakers (HSCB) are indispensable for protection of DC electric subway substations from fault current. However, the HSCB has mechanical contact to wear, which requires rather frequent maintenance, we have succeeded in developing and manufacturing a GTO DC circuit breaker using GTOs and ZnO varistors. In this paper, we describes the outline of the system itself, its characteristics and test data.

• 한국철도학회논문집
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• 제19권2호
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• pp.117-123
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• 2016

철도차량용 직류 고속도 차단기(HSCB)는 주 회로에 흐르고 있는 전류를 정상 차단시 아크 슈트 내부에서 발생아크를 소호하여 접지사고를 방지하는 기능으로 사용되고 있다. 선로에 사용되는 접촉기의 개방시에 발생하는 아크를 연구하기 위하여 아크 구현, 외부자계 등에 의한 효과적인 아크 소호의 방식 정립 및 아크 자기 구동력의 해석이 필요하다. 본 논문은 전자접촉기의 정상 차단시 발생하는 아크를 자속밀도 차와 로렌츠력을 통하여 소호능력을 예측하였다. 아크 슈트 내부의 그리드 개수와 형상은 내부 자계 형성에 영향을 미치므로, 유한 요소법을 이용하여 그리드의 변화에 따른 아크 소호능력을 연구하였으며 정격전압에 따른 그리드의 소호능력 평가와 그리드 형상 특성을 해석하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 B
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• pp.1362-1364
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• 2000

This paper presents the control algorithm verification process for VCB (Vacuum Circuit Breaker) of Korean High Speed Train. In order to enhance the reliability of the control algorithm, the verification process must be performed. The verification is conducted by comparing the pre-designed control algorithm with the pre-planned scenario by simulation tools such as SDL and MSC. This verification process will be applied to the other control algorithms of various control units of Korean High Speed Train.

• 한국기계가공학회지
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• 제21권9호
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• pp.78-84
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• 2022

An air circuit breaker (ACB) is an electrical protection device that interrupts abnormal fault currents that result from overloads or short circuits in a low-voltage power distribution line. The ACB consists of a main circuit part for current flow, mechanism part for the opening and closing operation of movable conductors, and arc-extinguishing part for arc extinction during the breaking operation. The driving mechanism of the ACB is a spring energy charging type. The faster the contact opening speed of the movable conductors during the opening process, the better the breaking performance. However, there is a disadvantage that the durability of mechanism decreases in inverse proportion to the use of a spring capable of accumulating high energy to configure the breaking speed faster. Therefore, to simultaneously satisfy the breaking performance and mechanical endurance of the ACB, its driving mechanism must be optimized. In this study, a dynamic model of the ACB was developed using the MDO(Mechanism Dynamics Option) module of CREO, which is widely used in multibody dynamics analysis. To improve the opening velocity, the Taguchi design method was applied to optimize the design parameters of an ACB with many linkages. In addition, to evaluate the improvement in the operating characteristics, the simulation and experimental results were compared with the MDO model and improved prototype sample, respectively.

• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.569-575
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• 2022

This is a research thesis on the development of a monitoring and diagnosis device that prevents the risk of an accident through monitoring and diagnosis of a modular Main Circuit Breaker (MCB) using Vacuum Interrupter (VI) for Korean high-speed rolling stock. In this paper, a comprehensive MCB monitoring and diagnosis was performed by converging vacuum level diagnosis of interrupter, operating coil monitoring of MCB and environmental temperature/humidity monitoring of modular box. In addition, to develop an algorithm that is expected to have a similar data processing before the actual field test of the MCB monitoring and diagnosis device in 2023, the cluster analysis and factor analysis were performed using the WEKA data mining technique on the big data of Korean railroad transformer, which was previously researched by Tae Hee Evolution with KORAIL.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.777-781
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• 1997

One of the spring-link mechanisms, the air circuit breaker(ACB), was studied to improve the shock-proof characteristics of it. The low-cycle fatigue fracture phenomenon was occurred on the critical link, called h-link, of ACB for the repeated rapid closing and opening operations. To analyze the cause of failure, dynamic FE-analysis on the h-link part of ACB was accomplished with considered the velocity and acceleration of the links per time as boundary conditions, which were obtained by using ADAMS. Then, to reduce the maximum tensile stress on the h-link, three types of h-link were suggested and one of them was selected. Fmm this study, we suggested the process of analysis on the high-speed motion behavior part related low-cycle fatigue fractures.