The Transactions of the Korean Institute of Electrical Engineers C (대한전기학회논문지:전기물성ㆍ응용부문C)

The Korean Institute of Electrical Engineers (대한전기학회)
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V-t Characteristics in $SF_6-N_2$ Mixtures for Transient Impulse Voltages

$SF_6-N_2$ 혼합가스에서 과도임펄스전압에 대한 V-t특성

  • 이복희 (인하대 전자전기컴퓨터공학부) ;
  • 이경옥 (인하대 사범대학 부속 고교 교사)
  • Published : 2001.09.01
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Abstract

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.

Keywords

References

  1. 山田 達司, 高橋 俊裕, 戶田 恒雄, 大久保 仁 : '各種ガスと$SF_6$による混合ガス中における部分放電の發生メカニズム,' 電學論B, 118卷 7/8號, pp. 837-842, 平成10年
  2. 이복희, 이경옥, 김정일, '$SF_6-N_2$ 혼합기체 중에서 불평등전계 갭의 임펄스 절연파괴 특성,' 전기학회논문지, Vol. 49, No. 9, pp. 533-540, 2000
  3. 吉田 智朗, 藤破 秀雄, 河本 正 : '$SF_6$ガスの雷サ-ジに對するV-t特性の檢討,' 電學論B, 116卷 10號, pp. 1232-1239, 平成8年
  4. B. Heers, A. Stepken : 'Investigation on Discharge Development in $SF_6$ for Oscillating Lightning Impulses and Fast Oscillating Overvoltages,' Proc. of 7th ISH, No. 31.06, pp. 29-32, 1991
  5. IEC International Standard 60060-1, Pt. 1, : 'General Definitions and Test Requirement,' 1999
  6. Dieter Kind :'Die Aufbauflache bei StroBspannungs-beanspruchung Technischer Elektrodenanordnungen in Luft,' Elektro Technische Zeitsschrift, 1958
  7. 이복희, 이경옥, 이창준, '가스절연개폐장치에 있어서 금속입자 존재시 임펄스전압에 대한 $SF_6$가스의 절연특성,' 조명. 전기설비학회 논문지, Vol. 14, No. 1, pp. 22-29, 2000
  8. N. H. Malik, A. H. Qureshi and G. D. Theophilus, 'Static Field Breakdown of $SF_6-N_2$ Mixtures in Rod-Plane Gaps,' IEEE Trans., Vol. EI-14, No. 2, pp. 61-69, 1979 https://doi.org/10.1109/TEI.1979.298157
  9. K. Tekletsadik and L. C. Campbell, '$SF_6$ Breakdown in GIS,' IEE Proc.-Meas. Technol., Vol. 143, No. 5, pp. 270-276, 1996 https://doi.org/10.1049/ip-smt:19960546
  10. J. K. Nelson, 'Positive Corona Processes in Electronegative Gaseous Dielectrics,' IEEE Trans., Vol. EI-20, No. 3, pp. 601-607, 1985 https://doi.org/10.1109/TEI.1985.348804
  11. K. Mardikyan, 'Breakdown Strength of Air, $SF_6$ and a Mixture of Air plus $SF_6$ Containing a Small Amount of $SF_6$,' ETEP, Vol. 9, No. 5, pp. 313-316, 1999
  12. N. Wiegart, et al. : 'Inhomogeneous Field Breakdown in GIS,' IEEE Trans., Vol. PD-3, No. 3, pp. 923-946, 1988
  13. K. Mardikyan, O. Kalenderli, O. Ersen, E. Canarslan, 'AC Breakdown Strength of $N_2,\;SF_6$ and a Mixture of $SF_{6+}N_2$, Containing a Small Amount of $SF_6$,' IEEE Int. Symp. on Elect. Insul., pp. 763-765, 1996
  14. 이복희, 이경옥, 이창준, 백승권 : '불평등전계 중에서 임펄스전압에 대한 $SF_6$기체의 전구방전과정의 분석,' 전기전자재료학회 논문지, Vol. 13, No. 1, pp. 85-93, 2000
  15. 이복희, 이경옥, 백승권, : '$SF_6-N_2$ 혼합기체중에 뇌임펄스전압에 의해 형성된 불평등전장에서의 전구방전현상,' 전기학회 논문지, pp. 288-295, 2001. 6