• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1822-1824
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• 1996

Damage and upset of control and communication equipment due to transient overvoltages which occur due primarily to internal switching surge and external lightning surge are an important problems in electromagnetic compatibility(EMC). In this paper, we analyzed operation characteristic of metal oxide varistor widely used low voltage AC line using the electromagnetic transients program(EMTP) and compare it with experimental results and also, we modeled combination generator producing $1.2/50{\mu}s$ open circuit voltage and $8/20{\mu}s$ short circuit current as a source which is critical in calculating operation characteristic. Simulation results showed that most of Transient energy consumes at MOV located in service entrance side than load side, and it showed similar to experimental results. Therefore, entrance side MOV should be selected more energy capacity than that of load side MOV.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 추계종합학술대회
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• pp.490-493
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• 1999

Due to the miniaturization of electrical components and assembles on signal and telecommunication circuits, transient overvoltages caused by switching operation or lightning surge has become more interesting concern to the field of electrical engineering. This paper describes the development of transient voltage blocking devices (TBDs) that can protect sensitive signal and telecommunication devices from overvoltages. Two kinds of TBDs are designed and tested by using a combination surge generator which can produce the standard impulse current of 8/20${\mu}$s 2.1kA according to the IEC 1000-4-5 standard. From the simulation and experimental reults, it is confirmed that the proposed TBD has an enough protection performance in low insertion loss and tight clamping voltage.

• 조명전기설비학회논문지
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• 제14권6호
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• pp.18-25
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• 2000

본 논문에서는 과도전압과 전원선 방해파로부터 가전기기틀 안전하게 보호할 수 있는 전자파 대용 단위세대 분전반의 설계 및 제작에 대하에 기술하였다. 제안한 분전반은 바리스터, 캐패시터 및 간선도채의 인덕턴스로 구성한 과도전업 차단장치와 전자파 필터를 내장하고 있다. 시제작한 분전반은 IEC 규격의 조합형 서지 발생장치와 회로밍 분석키를 이용하여, 과도전압에 대한차단특성과 전원선 방해파의 감쇠특성을 평가하였다. 실험 결과로부E] 본 연구에서 제안한 분전빈은 IEC 61000-4-5에 규정한 서지내생기준을 만족하였으며, 150[kHz]-30[MHz] 대역의 전원선 방해파에 대해 20[dB] 이상의 감소효과를 나타내었다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2000년도 춘계종합학술대회
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• pp.489-492
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• 2000

This paper describes a new transient voltage suppressor(TVS) with a low insertion loss and a very wide frequency bandwidth to protect antenna circuit from transient voltages. Conventional protection devices have some problems such as low frequency bandwidth and high insertion loss. In order to improve these limitations, a coaxal type TVS, which consists of a gas tube is developed. The performance of the proposed transient voltage suppressor is tested by using a combination surge generator specified in IEC 61000-4-5 standard and by using a network analyzer of 40 MHz ∼ 5GHz bandwidth. From the experimental results, it is confirmed that the proposed TVS has an enough protection performance in low insertion loss and in wide frequency bandwidth

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.1166-1169
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• 2005

This paper describes a new transient voltage suppressor(TVS) with a low insertion loss and a high cut-off frequency to protect antenna circuit from transient voltages. Conventional protection devices have some problems such as a low frequency bandwidth and a high insertion loss. In order to improve these limitations, a coaxal type TVS, which consists of a gas tube is developed. The performance of the proposed transient voltage suppressor is tested by using a combination surge generator specified in IEC 61000-4-5 standard and by using a network analyzer of 40 MHz ${\sim}$ 5 GHz bandwidth. From the experimental results, it is confirmed that the proposed TVS has an enough protection performance in a low insertion loss and a high cut-off frequency.

• Journal of Advanced Marine Engineering and Technology
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• 제23권2호
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• pp.159-167
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• 1999

This paper presents a new transient voltage blocking device(TOBD)which low power and high frequency bandwidth to protect info-communication facilities from transient voltages. Conventional protection devices have some problems such as low frequency bandwidth low ener-gy capacity and high remnant voltage. in order to improve these limitations a hybrid type TOBD which consists of a gas tube avalanche diodes and junction type field effect transistor (JFETs) is developed. The TOBD differs from the conventional protection devices in configuration and JFETs are used as an active non-linear element and a high speed switching diode with low capacitance limited high current. Therefore the avalanche diode with low energy capacity are protected from the high current and the TOBD has a very small input capacitance. From the performance test using combination surge generator which can produce $1.2/50{\mu}m$ 4.2 kV/max, $8/20{\mu}m$ 2.1 kAmax it is confirmed that the proposed TOBD has an excellent protection per-formance in tight clamping voltage and limiting current characteristics.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 추계종합학술대회
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• pp.486-489
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• 1999

This paper deals with the design rule and performance results of the transient voltage blocking devices (TBD) for low-voltage mains on shipboard. The proposed TBD consists of metal oxide varistors (MOV) and L-C filter to improve noise-elimination performance. Three kinds of TBDs are fabricated and tested by using a combination surge generator which can produce the standard impulse current of 8/20${\mu}$s 2.1kA. As a reults, the proposed TBD with series L-C filter has more excellent transient blocking and noise reduction performance than the conventional TBDs.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권1호
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• pp.51-56
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• 1999

This paper presents a new transient overvoltage blocking device (TOBD) for info-communication facilities with low power and high frequency bandwidth. Conventional protection devices have some problems such as low frequency bandwidth, low energy capacity and high remnant voltage. In order to improve these limitations, thehybrid type TOBD, which consists of a gas tube, avalanche diodes and junction typefield effect transistors (JFETs), was designed and fabricated. The TOBD differs from the conventional protection devices in configuration, and JFETs were used as an active non-linear element and a high speed switching diode with low capacitance limits high current. Therefore the avalanche dilde with low energy capacity are protected fromthe high current, and the TOBD has a very small input capacitance. From the performance test using combination surge generator, which can produce $1.2/50\mus\;4.2kV_{max}\; 8/20\mus\; 2.1kA_{max}$, it is confirmed that proposed TOBD has an excellent protection performance in tight clamping voltage and limiting current characteristics.

• Journal of Biosystems Engineering
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• 제12권1호
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• pp.45-52
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• 1987

엔진의 점화시기(點火時期)를 제어(制御)하는 데에 마이크로컴퓨터를 이용(利用)하고자 여러 종류(種類)의 제어장치(制御裝置)를 설계(設計) 제작(製作)하여 가동시험한 결과를 요약하면 다음과 같다. 가. 제어장치(制御裝置)의 제작시(製作時) 고압방전(高壓放電)에 의한 잡음(雜音), 서어지, 전자파(電磁波)로부터 디지탈회로와 컴퓨터의 기능(技能)이 교란되는 것을 방지하기 위하여는 고압회로(高壓回路)와 여타 회로와의 분리 및 고압회로의 기생발진 억제와 차폐가 완전하여야 할 것이며, 또한 양질의 점화용(點火用) 도선(導線)을 사용하여야 할 것으로 생각된다. 나. 본 실험의 범위내에서는(컴퓨터시스템) (써어보 기구에 의한 점화신호발생(點火信號發生) 및 제어(制御) - (트랜지스터 스위칭) - (고압회로) 로 구성(構成)시킨 점화시기제어장치가 컴퓨터 등의 기능교란을 일으키지 않고 가장 잘 작동(作動)되었다. 다. 본 실험의 결과(結果)를 기초(基礎)로 마이크로컴퓨터를 이용한 엔진의 최적점화진각제어(最適點火進角制御)에의 응용(應用)이 가능(可能)할 것으로 사료(思料)된다.