Effect of Solid Impurities on Breakdown in Compressed SF6 Gas

In compressed gas insulated systems, the problems of the conducting particles, which are suspected to cause the irregular breakdown in SF6 gas, are serious matter for design engineers. In this paper the effects of conducting particles and insulating fibers are described under alternating, impulse and alternating-impulse superposed voltage conditions. Those investigated results had been applied for 500kV gas insulated substation already put into service in Japan.