• 조명전기설비학회논문지
• /
• 제29권3호
• /
• pp.81-87
• /
• 2015

In order to effectively protect electrical and electronic circuits which are extremely susceptible to lightning surges, multi-stage surge protection circuits are required. This paper presents the operational characteristics of the two-stage hybrid surge protection circuit in extra-low voltage DC power lines. The hybrid surge protective device consists of the gas discharge tube, transient voltage suppressor, and series inductor. The response characteristics of the proposed hybrid surge protective device to combination waves were investigated. As a result, the proposed two-stage surge protective device to combination wave provides the tight clamping level of less than 50V. The firing of the gas discharge tube to lightning surges depends on the de-coupling inductance and the rate-of-change of the current flowing through the transient voltage suppressor. The coordination between the upstream and downstream components of the hybrid surge protective device was satisfactorily achieved. The inductance of a de-coupler in surge protective circuits for low-voltage DC power lines, relative to a resistance, is sufficiently effective. The voltage drop and power loss due to the proposed surge protective device are ignored during normal operation of the systems.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
• /
• pp.616-619
• /
• 2004

Lightning surge damages of low voltage equipments in building are increasing due to increase in electrical and communication networks in the information-oriented society. And electronic equipments contained electrical circuits with semiconductor are very weak against lightning surge. The surge protective devices for electronic circuit in electronic equipments and AC power lines are becoming more widely. To achieve effective method of surge protection, there are needs for correlation between lightning surge protective effect of electronic equipment and installation method of surge protective device. This paper describes as a result of experiments for correlation between lightning surge protective effect and installation method of surge protective device.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2005년도 추계학술대회 논문집 전기물성,응용부문
• /
• pp.90-92
• /
• 2005

Lightning surge damages of low voltage equipments in building are increasing due to increase in electrical and communication networks in the information-oriented society. And electronic equipments contained electrical circuits with semiconductor are very weak against lightning surge. The surge protective devices for electronic circuit in electronic equipments and AC power lines are becoming more widely. To achieve effective method of surge protection, there are needs for correlation between lightning surge protective effect of electronic equipment and installation method of surge protective device. This paper describes as a result of experiments for correlation between lightning surge protective effect and installation of surge protective device and Earth Leakage Breaker.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 추계학술대회 논문집 전기설비전문위원
• /
• pp.40-42
• /
• 2004

Electronic equipments made from electrical circuits with small-sized semiconductor are very weak against lightning surge. So, electronic equipments is protected by SPD(surge protective devices) such as Zno varistor. The SPD protect electronic circuit in electronic equipments and AC power lines from the lightning surge. Therefore to achieve effective method of surge protection, there are needs for correlation between lightning surge protective effect and installation method of surge protective device. Therefore this paper describes as a result of experiments for correlation between lightning surge protective effect and installation method of surge protective device.

• 한국조명전기설비학회지:조명전기설비
• /
• 제11권4호
• /
• pp.109-116
• /
• 1997

I본 논문은 교류 전원용 바리스터와 LC필터를 조합한 서지 보호장치에 대해서 기술하였다. 지금까지 교류 전류용 서지 보호장치로써 바리스터만이 주로 사용되어 왔으나, 이것은 급상승하고 높은 잔류전압 때문에 보호되어야 할 장비에 해로운 결과를 초래하는 경우도 있다. 따라서 본 연구에서는 교류 전원용 서지 보호장치의 차단 성능을 향상시키기 위하여 바리스터와 LC필터로 구성된 조합형 서지 보호장치를 설계.제작하였다. 그리고 서지 보호장치의 동작특성과 차단 성능의 분석에 대한 실험을 1.2/50[$\mu\textrm{s}$] 임펄스 발생기를 적용하여 수행하였다. 결론적으로 본 연구에서 제시한 조합형 서지보호장치는 서지 전압을 더욱 낮게 제한할 수 있고, dV/dt의 값을 매우 낮은 값으로 감소시키며, LC필터에 의한 출력단의 고주파 전압을 효과적으로 감쇠시킬수 있기 때문에 전자시스템의 손상과 전도를 더욱 더 효과적으로 방지할 수 있다.

• 조명전기설비학회논문지
• /
• 제27권6호
• /
• pp.75-81
• /
• 2013

In this paper, protection coordination between residual current devices and surge protective devices in low-voltage consumer's distribution systems are presented. In the case that a surge protrctive device(SPD) is located on the load side of an residual current device(RCD), when the surge is injected from the source side of the RCD, most of injected surge currents are split into the RCD and the protection coordination between the SPD and RCD is improper, three of 6 specimens experience unintended operation due to test impulse currents. Also when the surges is injected from the load side, a lot of the surge currents is split into the SPD, but a half of test specimens causes nuisance trip. Coordination between SPD and RCD is not valid. When installing SPD, it is important to select SPD after due consideration of the protection voltage level of metal oxide varistor embedded in RCD. It is expected that the results obtained from this work could be useful to improve the protection effects of SPD in low-voltage distribution systems.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 하계학술대회 논문집 C
• /
• pp.1873-1875
• /
• 1996

This paper deals with the lightning surge protective devices with combination of varistor and LC filter. UP to now, the varistor alone were used as overvoltage protection devices fer the AC power mains. In this work, in order to improve the cutoff performance of surge protective device, the hybrid circuit surge protective device for an AC single phase mains was designed and investigated. The first stage of hybrid circuit is to remove most of any large surge energy and protect the second stage components. The purpose of the second is to protect the load and increase the cutoff capacity of surge protective devices. Also LC filter attenuates the remnant that travels downstream from the first stage component and the high frequency noises. As a consequence, it was found that the proposed hybrid surge protective device for AC power mains has a variety of advantages such as low and tight clamping voltage, high frequency noise reduction and large cutoff capacity.

• 한국안전학회지
• /
• 제30권4호
• /
• pp.39-45
• /
• 2015

This paper deals with development of integrity evaluation instrument for the power line surge protective device. A reliable power supply is an essential element in the developed information and communication society by highly advances in IT technology. However, the lightning incidence also increased with the recent extreme weather events. In Korea, in order to protect the electrical system from lightning surge, SPD(Surge Protective Device) has been used for these past 30 years. However, the method of diagnosing the safety of the SPD in the industry is insufficient. In this paper, SPD integrity evaluation system was composed of a variable DC power source unit, voltage-current sensor and the embedded controller. In order to measure V-I characteristics of MOV, 3 type samples were degraded by impulse current generator. After impulse tests, the varistor voltage of all samples and nonlinearity coefficient were decreased. It confirmed the utility of the developed equipment by this experimental test and the reliability of SPD is expected for surge accident prevention when applied to industrial plant.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1996년도 추계학술대회 논문집 학회본부
• /
• pp.279-281
• /
• 1996

This paper deals with the two stage surge protection device by using varistor and LC low pass filter. Recently varistor alone has been used with overvoltage protection devices for the AC power mains and has same problems associated with high remnant voltage and noise. In this work, in order to improve the cutoff performance of surge protection device, the lightning surge protection device having two stage hybrid circuit for an AC single phase mains was designed and fabricated. Operation characteristics and surge clamping performance of the surge protection device in an $8/20{\mu}s$ surge current are investigated. As a consequence, it is found that the proposed two stage surge protective device for AC power mains has a variety of advantages such as a smaller clamping voltage, high frequency noise reduction and large clamping capacity.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2015년도 제46회 하계학술대회
• /
• pp.1213-1214
• /
• 2015

서지보호장치(Surge Protective Device)가 국내에 본격적으로 설치된 것은 산업화의 발전으로 인해 현장 전력시스템의 복잡성과 다양성 및 급격히 변화하고 있는 우리나의 기후변화 때문일 것이다. 전원계통의 전원용서지보호장치(Poser Systems Surge Protective Devices) 및 통신계통의 통신용서지보호장치(Telecommunication Surge Protective Devices)의 설치는 해마다 증가하고 있다. 이에 따른 제품개발도 급속도로 이루어지고 있으며, 과거 몇년 전만해도 서지보호장치에 대한 표준과 시험설비의 이해와 부족으로 인해 표준에 의한 제품검증이 어려웠으나 2013년 제정된 KS 표준(KS C IEC 61643-11)으로 상당수 제조자가 관련인증을 취득하고 있다. 이 논문에서는 KS표준에서 정의하고 있는 열안전성시험에 대한 방법과 결과판정 및 새로운 기준을 제시하고자 한다.