• 제목/요약/키워드: Breakdown field

검색결과 794건 처리시간 0.026초

바리스터의 전기적 특성 (The Electrical Characteristics of Varistor.)

  • 홍경진;장동환;조재철
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 춘계학술대회 논문집 센서 박막재료
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    • pp.52-56
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    • 2001
  • The Breakdown electric field of ZnO semiconductor devices in voltage-current characteristics was increased by increasing of additive materials. The specimen that has not additive materials was not formed spinel structure. The critical voltage that has not spinel structure was 235[V]. When the additive materials has 0.5 and 2[mol%], the Breakdown electric field was 840 and 758[V] in each additive materials. The Breakdown electric field of varistors as a factor of voltage and current was increased by addition of oxide antimony. The varistors that has oxide antimony was linearly increased in low electric field.

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GIS 립 스페이서에 대한 전계해석 및 절연특성 개선에 관한 연구 (A Study on the Electric Field Analyses and Improvement of Insulation Characteristics on the Ribbed Spaced for GIS)

  • 류성식;최영찬;곽희로
    • 조명전기설비학회논문지
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    • 제16권2호
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    • pp.59-64
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    • 2002
  • 본 논문에서는 전계해석을 통하여 금속성 파티클이 GIS 스페이서의 여러 위치에 부차되었을 경우 립이 파괴전압특성에 미치는 영향을 분석하였다. 또한, 립-스페이서의 여러 위치에 금속성 파티클을 부착하고 립의 모양, 길이, 두께 등의 변화에 따라 얻은 파괴진압특성 실험결과를 전계해석의 결과와 비교·검토하였다. 전계해석의 결과 립의 연면에서의 전계집중이 다른 부분에 비하며 완화되어 절연파괴시 발생된 스트리머의 진전이 억제될 수 있다는 것을 알 수 있었으며, 실험을 통하여 파괴전압이 상승된다는 것을 확인할 수 있었다. 또한 립의 길이와 두께 등에 따라서도 파괴전압 특성이 달라짐을 알 수 있었다. 또한 립의 끝단을 라운드 처리함으로써 파괴전압 특성을 더욱 향상시킬 수 있음을 전계해석과 실험을 통하여 알 수 있었다.

평등, 불평등 전계에서 AC전압의 $SF_6/CF_4$ 혼합가스 절연내력 특성 (Breakdown Characteristics of $SF_6/CF_4$ Mixtures under AC Voltages in Uniform, Nonuniform Field)

  • 성허경;황청호;김남렬;허창수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 제39회 하계학술대회
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    • pp.1334-1335
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    • 2008
  • Although many studies have been carried out about binary gas mixtures with $SF_6$, few studies were presented about breakdown characteristics of $SF_6/CF_4$ mixtures. At present study the breakdown characteristics of $SF_6/CF_4$ mixtures in uniform and nonuniform field was performed. The experiments were carried out under AC voltages. The sphere-sphere electrode whose gap distance was 1 mm was used and the point-plane electrode whose gap distance was 3 mm was used in a test chamber. $SF_6/CF_4$ mixture contained 20% $SF_6$ and 80% $CF_4$ and the experimental gas pressure ranged from 0.1 to 0.5 MPa. The results show that addition of $SF_6/CF_4$ mixtures increase AC breakdown voltages. In uniform field the breakdown voltages of gas were linearly increased according to the pressure. However in nonuniform field the breakdown voltages of gas were increased nonlinearly.

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$SF_6-N_2$ 혼합가스에서 과도임펄스전압에 대한 V-t특성 (V-t Characteristics in $SF_6-N_2$ Mixtures for Transient Impulse Voltages)

  • 이복희;이경옥
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권9호
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    • pp.456-465
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    • 2001
  • In this paper, breakdown voltages in $SF_6-N_2$ mixtures were experimentally investigated to understand characteristics of dielectric strength and physical phenomena in nonuniform field disturbed by a needle shape protrusion. The test voltages are the lightning impulse$(\pm1.2/44 \mus)$ and the damped oscillatory impulse$(\pm400 ns / 0.83 MHz)$ voltages which can be occurred by the operation of disconnecting switches in gas-insulated switchgears(GIS). The effects of the polarity and wave shape of the test voltages, and the gas pressure on the V-t characteristics were in detail examined. The V-t characteristic curves were measured in different two ways : (1) one is the method by taking the maximum voltage recorded at or prior to breakdown against the time to breakdown, that is, the Procedures recommended in IEC 60060-1, (2) the other is the method by taking the voltage at the instant of chopping against the time to breakdown. As a result, the V-t characteristics of $SF_6-N_2$ mixtures in nonuniform electric field were significantly affected by the polarity and wave shape of the applied voltages. The positive breakdown voltages resulted in lower breakdown voltages in the time ranges considered, and the V-t curves for the negative oscillatory impulse voltage were extended over the longer time range. For the lightning impulse voltages, the V-t curves obtained by IEC Pub. 60060-1 were nearly same with the V-t curves obtained by the voltage at the instant of chopping against the time to breakdown. It is clear that the actual breakdown voltages were much lower than the maximum voltages appearing at or prior to breakdown because of the displacement current produced as a result of the dV/dt during the oscillatory transient voltage app1ication. The scattering of the negative actual breakdown voltages was much larger than that of the positive.

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내압특성개선을 위한 트렌치 필드링 설계 및 전기적특성에 관한 연구 (A Study on Electrical Characteristics of Trench Field Ring for Breakdown Characteristics)

  • 강이구;김범준;이용훈
    • 한국전기전자재료학회논문지
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    • 제23권1호
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    • pp.1-5
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    • 2010
  • In this paper, we proposed trench field ring for breakdown voltage of power devices. The proposed trench field ring was improved 10% efficiency comparing with conventional field ring. we analyzed five parameters of trench field ring for design of trench field ring and carried out 2-D devices simulation and process simulations. That is, we analyzed number of field ring, juction depth, distance of field rings, trench width, doping profield. The proposed trench field ring was better to more 1000 V.

광유 중 절연파괴전압의 분산과 절연파괴진전 과정의 분석 (Analysis of Breakdown Voltage Dispersion and Breakdown Process in Mineral Oil)

  • 임동영;박숭규;박철호;김기채;이광식;최은혁
    • 조명전기설비학회논문지
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    • 제29권6호
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    • pp.35-41
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    • 2015
  • This paper presents a breakdown voltage and a process of breakdown progress in mineral oil under an quasi-uniform field with decomposition products which occur after the oil discharge. The breakdown voltage in the oil revealed the characteristics of dispersion regardless of an electrode gap. The cumulative probability distribution was used to analyze the dispersion of the breakdown voltage. In addition, the process of breakdown progress in the oil can be reasonably described by the electron breakdown theory based on both electrons emitted from the cathode and ions by field-aided dissociation of the oil. The proposed breakdown process will be used for the basic data to explain the behavior pattern of the decomposition product to cause the dispersion of the breakdown voltage.

공기중 절연파괴에 있어서 전극표면의 요철에 의한 영향 (The Effect of Surface Roughness on Breakdown in Air)

  • 오철한;김미태
    • 전기의세계
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    • 제28권11호
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    • pp.33-36
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    • 1979
  • In a uniform field, when an electrode with a hemispherical protrusion is set in atmosphere, by applying the streamer breakdown criterion and the surface roughness factor, the effect of field distortion due to electrode surface roughness on breakdown is investigated theoretically. A quantitative relation between the threshold of breakdown and the air pressure times the heigh of protrusion is derived by the aid of a computor and the results are compared with that of SF$_{6}$./.

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에폭시 복합체의 실리콘유중 연면파괴에 관한 연구 (A Study on The Surface Breakdown of Epoxy Composite in Silicon Oil)

  • 장인범;정인재;정일형;유재웅;오재한;김종헌;이준웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
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    • pp.195-198
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    • 1998
  • In this paper, we study on the surface breakdown of Epoxy composite in silicon oil. Breakdown field strengths were simulated by using FEM with the experience data of surface breakdown of Epoxy composite. The surface endurance and field distribution (kV/mm) of Epoxy composite were calculated by FEM.

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라디오 주파수전계에 의한 질소가스의 브레이크 다운 현상 (The Breakdown Phenomena of N2 gas by RF Electric Field)

  • 황기웅;노영수
    • 대한전기학회논문지
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    • 제35권5호
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    • pp.199-204
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    • 1986
  • The breakdown phenomena of N2 gas by 13.56MHz electric field are very different from those under steady field. In this paper we analyzed the breakdown phenomena by using electron distribution function and diffusion equation. The second-order differential equation derived from the Boltzmann equation is solved for the electron distribution function. The ionization rate and diffusion coefficient are calculated using kinetic theory formulas. The breakdown condition is that the number of electrons produced by ionization equal the number diffusing to the walls of the discharge chamber. Theses theoretical breakdown electric fields are calculated by the computer and compared with the experimental values.

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트렌치 케이트 하단의 게이트 산화막 확장을 통한 트렌치 IGBT의 항복전압 향상에 대한 연구 (A Study on Breakdown Voltage Improvement of the Trench IGBT by Extending a Gate Oxide Region beneath the Trench Gate)

  • 이재인;경신수;최종찬;성만영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.74-75
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    • 2008
  • TIGBT has some merits which are lower on-state voltage drop and smaller cell pitch, but also has a defect which is relatively lower breakdown voltage in comparison with planar IGBT. This lower breakdown voltage is due to the electric field which is concentrated on beneath the vertical gate. Therefore in this paper, new trench IGBT structure is proposed to improve breakdown voltage In the new proposed structure, a narrow oxide beneath the trench gate edge where the electric field is concentrated is extended into rectangular shape to decrease the electric field. As a result, breakdown voltage is improved to 23%.

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