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DC 배전용 반도체차단기의 EMC 시험기준 및 방법에 대한 연구
조영만(Young-maan Cho),이예나(Ye-na Lee) 대한전기학회 2021 대한전기학회 학술대회 논문집 Vol.2021 No.11
The circuit breaker uses to protect the load from inrush of the over-current. And various type of circuit breakers are installed in the power transmission and distribution system according to required specifications. With the recent increase in interest in d.c. power distribution, research on d.c. circuit breaker is also actively progressing. Among them, the solid stated circuit breaker has the advantage of high lifespan because no arc occurs between contacts during the interruption precess and easy adjustment of current setting with operation time. In this paper, the difference between the interruption process of the conventional circuit breaker and the solid state circuit breaker are analyzed, and the test items and criteria required for the electromagnetic compatibility test of the solid state circuit breaker are proposed.
복합소호형 고압차단기 O-CO 동작 차단특성 분석 연구
송태헌(Tae-hun Song),조영만(Young-Maan Cho),고광철(Kwang-Cheol Ko) 한국조명·전기설비학회 2016 조명·전기설비학회논문지 Vol.30 No.4
The function of high voltage circuit breaker is to clear the fault current and protect the equipment in a power network when the overload or short circuit is generated in the network. High voltage circuit breaker should interrupt short circuit currents not only under Open operation for minimum arcing time but also under Open-CloseOpen operation for maximum arcing time. Self-blast type high voltage circuit breaker often fails to interrupt the short circuit current under the Open-CloseOpen operation condition. In this study, analysis of arc extinction characteristics under the Open-CloseOpen operation for maximum arcing time has been conducted for the self-blast type high voltage circuit breaker. Arc extinction phenomena were analyzed by simulation that was developed based on computational fluid dynamics. Arc simulations for high voltage circuit breaker use compressible gas dynamic equations(e.g. Navier-Stokes equations) including Ohmic input, Lorentz force and radiation transport. Relevant Maxwell’s equations are included for the calculation of electromagnetic fields. The simulation results show that the arc extinction performance of the Open-CloseOpen operation is severely affected by the conditions of remaining thermal gas in the thermal expansion chamber after the first Open operation.
이성근(Sung-Gyen Lee),조영만(Young-Maan Cho),고광철(Kwang-Cheol Ko) 한국조명·전기설비학회 2013 조명·전기설비학회논문지 Vol.27 No.12
In high-speed train, the EMI is generated by pantograph detachment and switching device of motor-block. Especially, the conductive noise flows through rail as return feeder influences unintended results to sub-station, transformer, etc. These phenomena were investigated by PSIM circuit analysis tool and each part of railway system is modeled by circuit elements and switching devices. Consequently, the distorted wave in return feeder current occurs by the high speed switching frequency, and the overvoltage is applied by the pantograph detachment. Also the distortion of return current is high in starting point and it decreases from the proximity of a starting point ro the end of terminal.