Title :
Optimum SF6-N2, SF6-air, SF6 -CO2 mixtures based on particle contamination
Author_Institution :
Dept. of Electr. Eng., Fac. of Eng., Cairo, Egypt
Abstract :
The design stress of sulphur hexafluoride Gas Insulated Switchgear (GIS) systems are limited by the harmful effects resulting from the almost inevitable presence of particulate contamination in GIS equipment. Mixing SF6 with other gas is a possible way of improving GIS performance under particle contamination condition. This paper studies the breakdown of SF6-gas mixture (SF6-air, SF6-N2 and SF6-C 4) in the presence of contaminating particles under applied DC voltage. The effect of particle dimensions on the breakdown voltage and so on the particle contamination factor (PCF) is presented in this work. The breakdown voltage-pressure characteristics for SF6-gas mixture with different fractional concentration of SF 6 in mixture are carried out. Also, the particle contamination sensitivity is sought for different parameters and to obtain the optimum SF6-gas mixtures for the case study. From this study it is concluded that some SF6-gas mixtures have breakdown gradients comparable to that of pure SF6 and are less sensitive to the presence of strong localized fields
Keywords :
SF6 insulation; discharges (electric); electric strength; gas insulated switchgear; gas mixtures; CO2; N2; SF6; SF6-CO2; SF6-N2; SF6-air mixture; SF6-gas mixture; applied DC voltage; breakdown gradients; breakdown voltage; contamination factor; contamination sensitivity; design stress; dielectric strength; gas insulated switchgear; optimum mixtures; particle contamination; streamer formation; strong localized fields; Breakdown voltage; Contamination; Costs; Dielectric breakdown; Electric breakdown; Gases; Ionization; Nitrogen; Pollution measurement; Sulfur hexafluoride;
Conference_Titel :
Electrical Insulation, 2000. Conference Record of the 2000 IEEE International Symposium on
Conference_Location :
Anaheim, CA
Print_ISBN :
0-7803-5931-3
DOI :
10.1109/ELINSL.2000.845510
