Title :
Breakdown voltage characteristics of SF6/CF4 mixtures in uniform and non-uniform field gaps
Author :
Berg, J. ; Kuffel, E.
Author_Institution :
Dept. of Electr. & Comput. Eng., Manitoba Univ., Winnipeg, Man., Canada
Abstract :
Binary gas mixtures consisting of sulfur hexafluoride (SF6 ) and carbon tetrafluoride (CF4) have been used for several years in the design of circuit breakers and electrical switchgear manufactured for operation in geographic regions of extremely low temperature. CF4, which has a liquifaction temperature comparable to that of nitrogen (N2) greatly reduces the risk of liquifaction and the loss of insulation of electrical equipment when mixed with SF6 at practical pressures (200-400 kPa). This paper presents experimental results on breakdown characteristics for various mixtures of SF6/CF4 at practical pressures. Data for power frequency alternating and positive polarity direct voltages, as well as standard lightning impulse voltages are presented for uniform, quasi-uniform and highly non-uniform electrode configurations and for various gap lengths
Keywords :
SF6 insulation; circuit breakers; electric breakdown; gas insulated switchgear; gas mixtures; impulse testing; organic compounds; 200 to 400 kPa; SF6; alternating voltages; binary gas mixtures; breakdown voltages; carbon tetrafluoride; circuit breakers; electrical equipment; electrical switchgear; insulation; lightning impulse voltages; liquifaction temperature; low temperature operation; nonuniform field gaps; positive polarity direct voltages; sulfur hexafluoride; uniform field gaps; Breakdown voltage; Circuit breakers; Dielectrics and electrical insulation; Electric breakdown; Frequency; Manufacturing; Nitrogen; Sulfur hexafluoride; Switchgear; Temperature;
Conference_Titel :
Electrical Insulation and Dielectric Phenomena, 1995. Annual Report., Conference on
Conference_Location :
Virginia Beach, VA
Print_ISBN :
0-7803-2931-7
DOI :
10.1109/CEIDP.1995.483592
