SLI, AC Breakdown Voltage Characteristics of $SF_6/CF_4$ Mixtures Gas in Nonuniform Field

불평등전계에서 $SF_6/CF_4$ 혼합 가스의 SLI, AC 절연내력 특성

  • Published : 2008.02.01

Abstract

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 non-uniform field was performed. The experiments were carried out under AC voltage and standard lightning impulse(SLI) voltage. Breakdown characteristics were investigated for $SF_6/CF_4$ mixtures when AC voltages and standard lighting impulse voltage was applied in a needle-plane. The needle-plane electrode whose gap distance was 3 mm were used in a test chamber. $SF_6/CF_4$ mixtures contained from 0 to 100% $SF_6$ and the experimental gas pressure ranged from 0.1 to 0.5 MPa. The breakdown characteristics of $SF_6/CF_4$ mixtures in non-uniform field may be influenced by defects like needle-shaped protrusions. In case of slowly rising SLI voltage and AC voltage it is enhanced by corona-stabilization. This phenomena caused by the ion drift during streamer development and the resulting space-charge is investigated. In non-uniform field under negative SLI voltage the breakdown voltage was increase linearly but under positive SLI voltage the breakdown voltage increase non-linearly. The breakdown voltage in needle-plane electrode displayed N shape characteristics for increasing the content of $SF_6$ at AC voltage. $SF_6/CF_4$ mixture has good dielectric strength and arc-extinguishing properties than pure SF6. This paper presents experimental results on breakdown characteristics for various mixtures of $SF_6/CF_4$ at practical pressures. We could make an environment friendly gas insulation material with maintaining dielectric strength by combing $SF_6\;and\;CF_4$ which generates a lower lever of the global warming effect.

References

  1. M. L. Trudeau, M. F. Frechette and R. Y. Laroque, " Sparks in SF6 and SF6/CF4 Atmospheres : impact on metallic and insulating surfaces". conference Record of the IEEE International Symposium on Electrical Insulation, Montreal, Quebec, Canada, June 16-19, 1996
  2. W. Ziomek and E. Kuffel, "Breakdown and prebreakdown characteristics of SF6/CF4 mixtures in non-uniform electric field", High Voltage Engineering, Eleventh International Sysposium on Conf. Vol.3, No. 467, p.243, 1999
  3. Y. Qiu, Y. P. Feng, "Investigation of SF6-N2, SF6-CO2 and SF6-air as substitutes for SF6 insulation", IEEE International Symposium on Electrical Insulation, Vol.2, p. 766, 1996
  4. 황청호, 박신우, 김남렬, 허창수. "평등전계에서 SF6/CF4 혼합 가스의 AC 절연내력 특성", 한국전기전자재료학회지, vol. 20, No.4, p. 381, April 2007 https://doi.org/10.4313/JKEM.2007.20.4.381
  5. 송병두, 하성철, "볼츠만 방정식에 의한 $CF_4$ 분자 가스의 전자이동속도특성에 관한 연구", 전기전자재료학회논문지, Vol.17, No.11, p.1252, November 2004
  6. M. Zou and J. P. Reynders, "Synergy between SF6 and other gases to enhance dielectric strength", 10th International Symposium on High Voltage Engineering, p.251, 1997
  7. 서호준, 이동희, "$SF_6계$ 혼합 가스의 뇌임펄스 절연파괴 특성", 전기전자재료학회, Vol.18, No.7, p.667, 2005 https://doi.org/10.4313/JKEM.2005.18.7.675
  8. V. N. Maller and M. S. Naidu, "Advances in High Voltage Insulation And Arc Interruption in $SF_6$ And Vacuum", Pergamon press, pp.1-11, 1981
  9. D. Kind and K. Feser, "High-voltage test techniques", Newnes, p. 14. 2001
  10. G. J. Cliteur, Y. Hayashi, E. Haginomori, K.Suzuki, "Calculation of the uniform breakdown field strength of $SF_6$ Gas", IEEE Transactions on Dielectrics and Electrical Insulation, Vol.5, No. 6, p.847, 1998
  11. 서상현, 유회영, 김상남, 하성철, "$SF_6$ 가스의 전리 및 부착계수에 관한 연구", 조명 전기설비학회지 Vol.10, No.6, p. 622, 1996
  12. J. Berg, E. Kuffel, "Breakdown voltage characteristics of SF6/CF4 mixtures in uniform and non-uniform field gaps", Electrical Insulation and Dielectric Phenomena, Annual Report., Conf, p. 126 - 129, 1995
  13. T. Nitta, N. Yamada, Y. Fujiwara, "Area effect of electrical breakdown in compressed $SF_6$", IEEE Transactions on Power Apparatus and Systems, Volume PAS-93, Issue. 2, p.625, 1974