• 전기학회논문지
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• 제59권11호
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• pp.2089-2092
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• 2010

There are many cases that interrupt the production process because of malfunctions caused by electronic circuit boards which control equipment, but it is difficult to distinctly identify the causes in many cases. Especially, CMOS devices with the control logic circuit return automatically to normal state after their own faults. Therefore it is not easy to analyze the problems with electronic circuit boards. Recently, nuclear power plant experienced a failure due to the malfunction of electronic circuit boards and it was identified that the reason of the malfunction was because of latch-up phenomenon caused by external surge in electronic devices. This paper presents the causes and the phenomenon of latch-up by experiment and also a way using counter EMF diodes, noise filters and surge protective devices to prevent latch-up phenomenon from electronic circuit boards, finally confirms the effectiveness of the result by experiment.

• 전자공학회논문지C
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• 제36C권7호
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• pp.17-26
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• 1999

본 논문에서는 접속된 주변장치와 데이터를 비동기로 교환 할 수 있는 접속 비트 전환식 양방향 접속 장치 설계에 대하여 기술한다. 특히 인터럽트 발생기를 설계하기 위해서 제시된 펄스형 순차회로 파형을 합성할 수 있는 진리치 비교 알고리즘을 제안하고 이를 인터럽트 레지스터 설계에 적용한 것에 대하여 상술하였다. 또한 개별 비트 출력 신호들의 클럭 스큐 현상을 없애기 위한 최종 출력 핀 제어 기법을 시스템에 적용하였으며 나머지 블록들을 설계한 기법에 대하여도 상술하였다. 이러한 기법을 사용함으로써 본 논문의 접속 포트들은 0.7ns 이내의 지연시간을 나타내었다.

• 전력전자학회논문지
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• 제9권4호
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• pp.390-396
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• 2004

최근 설비에 대한 고 역률과 저고조파의 요구가 증가하고 있어 국제적으로 고조파에 대한 규제가 강화되고 있다. 고조파를 줄이고 규제에 적합하기 위하여 역률 개선(PFC) 회로가 일반적으로 사용되어지고 있다. 이러한 역률개선 (PFC)회로의 제어방법으로 중, 대용량 스위칭 전원장치에 가장 적합한 것으로 알려진 평균 전류 제어방식이 가장 많이 사용되어지고 있다. 그러나 순시 정전이 된 후 복전 시 역률개선회로의 스위칭 소자가 빈번하게 파손이 되고있다. 본 논문에서는 이러한 문제점의 원인을 규명하고 해결 방법을 제안하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.144-146
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• 2002

The latest development flow of MCCB(Molded Case Circuit Breaker) is largely separated from which are high capability of interrupting compact of size and multi-ability in functions. As follow of development of industrial system. MCCB which are including communication function and having a ultimate interrupting capability is required in electrical system. to attain an effective limitation of the peak let-through current and the let-through energy, the arc has to move rapidly off the contacts and has to increase the arc voltage which mainly effect to interrupt. In this paper. we made high performance circuit breaker which including current limiting unit which is attached to the main which is simulated by CAE tool that are repulsion force and mechanical dynamics after that we tested and finally selected optimized for circuit breaker.

• 대한전자공학회논문지
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• 제14권5호
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• pp.1-6
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• 1977

synchronizer의 입력단에 비동기된 두 신호가 인가되었을 때 일어나는 Metastable 현상에 대한 회로의 해석과 Metastable point에서 stable state로 천이되는 과정에서 일어나는 현상을 해석하였으며, 이러한 mishappen 상태에 의해 기인하는 logic failure를 개선하기 위한 방법으로써, Inverter Method, open collector Method를 사용하여 올바른 논리를 이론과 실험을 통하여 구현하였다.

• Journal of Power Electronics
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• 제17권1호
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• pp.272-281
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• 2017

The DC circuit breaker is essential for supplying stable DC power with the advent of DC transmission/distribution and sensitive loads. Compared with mechanical circuit breakers, which must interrupt a very large fault current due to their slow breaking capability, a solid-state circuit breaker (SSCB) can quickly break a fault current almost within 1 [ms]. Thus, it can reduce the damage of an accident a lot more than mechanical circuit breakers. However, previous DC SSCBs cannot perform the operating duty, and are not economical because many SCR are required. Therefore, this paper proposes a new DC SSCB suitable for DC grids. It has a low semiconductor conduction loss, quick reclosing and rebreaking capabilities. As a result, it can perform the operating duties of reclosing and rebreaking. The proposed DC SSCB is designed and implemented so that it is suitable for home dc distribution at a rated power of 5 [kW] and a voltage of 380 [V]. The operating characteristics are confirmed by simulation and experimental results. In addition, this paper suggests design guidelines so that it can be applied to other DC grids. It is anticipated that the proposed DC SSCB may be utilized to design and realize many DC grid systems.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.105-105
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• 2010

Voltage circuit breakers are widely used in power distribution systems to interrupt fault current rapidly and to assure the reliability of the power supply. Power distribution system requires the transformer with higher capacity than ever, but this ever, but this may be the cause. of the increasing of short circuit current in contrast to conventional one when short-circuit accident is occurred. Therefore molded case circuit breaker improved in aspects of interrupting capacity of short circuit current in this system is needed. By using the proposed methods in this paper, such as new arc quenching structure of grid would contribute to minimizing the MCCB, realization of high interrupting performance and reducing the design time and development cost.

• 대한전기학회논문지:시스템및제어부문D
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• 제55권5호
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• pp.220-225
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• 2006

Arc Fault Current is an electric discharge which is occurred in two opposite electrode. In this paper, AFCI(arc fault circuit interrupter) is designed for the interruption of arc fault current which is occurred in the local electric network. This arc is one of the main causes of electric fire. Arc fault in electrical network has the characteristics of low current, high impedance and high frequency. Conventional arc fault circuit interrupter does not have the arc current interrupt function. Hence, Arc current controller is designed for the interruption of arc fault current which has the modified arc characteristics.

• 동력기계공학회지
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• 제3권2호
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• pp.64-69
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• 1999

The paper shows a result for development of BLDC motor drive by using a resolver as position detection sensor. The developed drive use a method detecting rotor position based on HSI interrupt function of microprocessor without a specialized counting circuit. The algorithm generating three-phase PWM wave to change switching voltage and current is realized based on single chip microprocessor. The PWM generating part and position counting circuit are realized by software technique without usage of conventional analogue circuit or object-oriented chips. So the drive system become compact. The effectiveness of the developed drive is verified by experimented results of speed response for step reference input.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 춘계학술대회 논문집 유기절연재료 전자세라믹 방전플라즈마 연구회
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• pp.51-54
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• 2001

This Paper is described basic principles of arc quenching in Molded Case Circuit Breaker. We analyzed magnetic blowout forces acting on the arc in contact system when circuit breakers interrupt fault currents in different three models by 3-D FEM(Finite Element Method). The interrupting time simulated is compared with that of short circuit tests. The results of this study derive valid of the simulation method and present the techniques to improve arc quenching performance.