• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1145-1148
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• 1999

This paper is introducing a newly developed spark gap switch with dual trigger system, into which the current from the voltage source is injected along wi th the test sequence during the synthetic testing of high voltage circuit-breaker.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1810-1812
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• 1996

This paper deals with the surge protective devices to minimize damages of communication equipments in signal data lines. The basic circuit consists of zener diodes, spark gap and series impedances. Therefore the hybrid circuit using bipolar zener diodes as clamps and a three-electrode spark gap as crowbars was proposed. The surge suppression performances and the characteristics of frequency response were investigated experimentally. Consequently, it was found that the frequency bandwidth and surge suppression performances are excellent.

• Journal of Electrical Engineering and Technology
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• 제8권1호
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• pp.150-155
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• 2013

A high voltage and nanosecond Blumlein pulse generator has been developed to produce an output pulse whose voltage level is greater than 250 kV and pulse duration 5 ns. The generator consists of various components such as a charging circuit, a pulse transformer, and a spark gap switch. As a heart of the generator, a Blumlein pulse forming line has been constructed in the cylindrical form using three cylindrical aluminum electrodes that are placed concentrically. Unlike the ideal Blumlein line, the output pulse of an actual Blumlein line may be affected by stray inductances and capacitances of switching and charging components, thereby degrading the performance of the generator. In this paper, PSPICE simulations have been performed to examine effects of stray inductances and capacitances on waveforms of output pulses. Simulation results show that the pulse waveform is significantly distorted mainly by the stray inductance of the spark gap switch.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1766-1768
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• 2002

The current density in the IPS(Inverse Pinch Switch) is 1/62 times less than that in the spark gap. It was shown that in comparison with the spark gap, the switch inductance of the IPS is largely reduced and the useful lifetime is significantly increased. In the paper, the design technology of a closing switch, especially IPS triggered by electrical signal for pulsed power system with a very high voltage and current is presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 전력전자학술대회 논문집
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• pp.153-154
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• 2013

고전압, 대전류를 갖는 뇌서지는 전원회로에 유입되었을 때 소자 파손 및 회로 오동작 등의 문제를 일으킨다. 이에 대한 보호대책으로 SPD(Surge Protection Device)소자와 스파크-갭(Spark-gap)을 주로 사용한다. 이 때, 기존의 스파크-갭은 뇌서지 유입 시 방전현상 이후에 발생된 스파크-갭의 패턴 마모로 패턴의 복구가 불가능하고, 불규칙하고 변칙적인 방전으로 인하여 발생되는 서지주요 예측경로의 소자 및 패턴 파괴와 같이 2차적인 문제를 발생시킨다. 이를 해결하기 위해 본 논문에서는 초기 유입 시부터 스파크-갭의 방전을 통해 에너지를 우회시킴으로서 전원회로의 뇌서지 부담을 줄여 전원회로의 안전성 및 안정적인 정상동작을 확보하는 대책을 제안하고, 스파크-갭의 구조에 따른 효과를 실험을 통해 검증한다.

• 한국광학회지
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• 제1권2호
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• pp.169-177
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• 1990

레이저관내에 별도의 전극을 설치하지 않고 레이저전극 자체만으로 선전리 효과를 얻을 수 있는 질소레이저를 연구하였다. 이를 위하여 펄스형 전원과 고속고전압 방전간극을 사용하는 레이저를 제작하였으며, 레이저관 양단에는 저항 또는 인덕터를 연결하여 이들이 레이저 동작특성에 미치는 영향과 자체 선전리 효과를 함께 연구하였다.

• 한국공작기계학회논문집
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• 제15권6호
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• pp.15-21
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• 2006

This work deals with the electrical conductivity of dielectric on output parameters such as metal removal rate and surface roughness value of a carbon steel(SM25C) and sintered carbides cut by wire electrical discharge machining (WEDM). Dielectric has several functions like insulation, ionization, cooling, the removal of waste metal particles. The presence of minute metal particles(debris) in spark gap contaminates and lowers the breakdown strength of dielectric. And it is considered that too much debris in spark gap is generally believed to be the cause of arcing. Experimental results show that increases of cobalt amount in carbides affects the metal removal rate and worsens the surface quality as a greater quantity of solidified metal deposits on the eroded surface. Lower electrical conductivity of the dielectric results in a lower metal removal rate because the gap between wire electrode and workpiece reduced. Especially, the surface characteristics of rough-cut workpiece and wire electrode were analyzed too. Debris were analyzed also through scanning electron microscopy(SEM) and surface roughness tester. Micro cracks and some of electrode material are found on the workpiece surface by energy dispersive spectrometer(EDS).

• 대한기계학회논문집
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• 제17권2호
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• pp.380-384
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• 1993

In precision wire electrode discharge machining by CAD/CAM, it is the most important problem on machining method to determine the wire electrode offset amout from the accurate calculation of discharge gap in order to increase the machining accuracy, after fixing the main machining conditions such as machining speed, wire tension, coolant conductivity, gap vlotage. The present study shows the relationships between discharge gap and main machining conditions by means of a series of experiment concerned with the gap using the workpiece of STD 11, and suggests the experimental eguation to calculate the accurate wire electrode offset amount under the given machining conditions for spot workers.

• 한국가스학회지
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• 제1권1호
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• pp.1-6
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• 1997

가연성 가스가 존재하는 위험 분위기에서 전기기기를 사용할 경우 전기 스파크에 의한 폭발위험성이 존재하기 때문에 점화원을 격리시키거나 고립시키는 것이 필요하지만 현실적으로 점화원의 고립이 불가능하므로 폭발을 방지하기 위한 일반적인 방법으로 내압 방폭형전기기기를 사용하고 있다. 따라서 내압방폭기기의 내부에 침투한 가연성 가스가 폭발하여도 화염이나 열이 틈새를 통과하여 외부의 가연성 분위기를 점화시킬 수 없는 최대 틈새크기를 찾아야 할 필요가 있다. 본 논문에서는 수소-공기 혼합기와 메탄-공기 혼합기에 대하여 실험적 최대틈새크기(MESG)를 찾아내어 기존의 결과와 비교하고, MESG에 영향을 미치는 요인들을 찾아내고자 하였다. 실험장치는 내용적 8${\iota}$의 구형용기를 사용하였으며 실험 변수들로는 전화위치, 혼합기의 농도, 초기압력 등이었다. 실험결과 각각의 변수들에 의해 영향을 받으며 특히 농도와 초기압력에 크게 영향을 받는 것을 알 수 있었으며, 당량 농도 가까이에서 최소값을 나타내었으며 초기압력의 상승과 함께 MESG는 감소하였다.

• 한국분무공학회지
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• 제14권4호
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• pp.171-177
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• 2009

This study proposes a new stratified charge system for low emission and ultra lean burn. In order to examine combustion characteristics of the new system, sparkplug with a hole at positive pole and a common CNG injector for injecting fuel were used in this study as injector-type spark plug. The new stratified charge system injects fuel of extremely small quantities and ignites mixture around sparkplug gap. Also, the system was fitted in a visualized constant volume chamber. Then, for analysis of the combustion characteristics, we examined combustion pressure, lean inflammable limit, and visualized combustion flame according to equivalence ratio by comparison with homogeneous charge (HC) method and the new stratified charge (SC) method. As results of this study, in the case of using this system, the propagation speed of initial flame was increased and total combustion period was reduced in the ultra lean burn in the same equivalence ratio. These phenomena occurred clearly under the conditions of lean equivalence ratio. Furthermore, the lean inflammable limit of mixture was extended by using the injector-type spark plug.