Title :
Comparison of SF6/N2 and SF6/CO 2 gas mixtures as alternatives to SF6 gas
Author :
Qiu, Y. ; Kuffel, E.
Author_Institution :
Sch. of Electr. Eng., Xi´´an Jiaotong Univ., China
fDate :
12/1/1999 12:00:00 AM
Abstract :
The interest in SF6 gas mixtures has been re-ignited in recent years by the issue of the greenhouse effect of the SF6 gas, and most research work is now focused on a SF6/N2 gas mixture, which is suitable for application in electrical apparatus with slightly non-uniform fields. This paper presents a comparison of SF6/N2 and SF6/CO2 gas mixtures with a viewpoint of their possible applications to gas-insulated transformers, where both highly non-uniform field problems and partial discharges in gas/film insulation are inevitable. It is shown that in this case the dielectric strength of SF6/CO2 is superior to that of SF6/N 2 with a minor disadvantage related to the gas decomposition in SF6/CO2. However, this may not be a problem for the SF6/CO2 gas mixture to be used in gas-insulated transformers, where internal breakdown is not allowed
Keywords :
SF6 insulation; carbon compounds; dissociation; electric strength; gas insulated transformers; gas mixtures; nitrogen; partial discharges; SF6; SF6-CO2; SF6-N2; SF6/CO2 gas mixtures; SF6/N2 gas mixtures; dielectric strength; electrical apparatus; gas decomposition; gas-insulated transformers; gas/film insulation; greenhouse effect; highly nonuniform field problems; partial discharges; slightly nonuniform fields; uniform field breakdown; Breakdown voltage; Dielectric breakdown; Electric breakdown; Electrodes; Equations; Microscopy; Nonuniform electric fields; Rough surfaces; Sulfur hexafluoride; Surface roughness;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
