170[㎸] GIB 내에서 건조공기(Dry Air)의 절연파괴 특성

In this paper, we changed SF? insulation gases used already in the GIB(Gas Insulated Bus, gas insulated busbar) of switching appliances of power grid 170[㎸] GIS(Gas Insulated Switchgear, Gas Insulated Switchgear) with green insulation dry air gases and studied dielectric breakdown voltage characteristics by the AC voltage withstand test. Withstand test AC voltage applied to the standard KEPCO's 170[㎸] GIB with dry air insulation and and the equivalent of dry air and SF? gas were examined. Breakdown voltage of dry air, using an expression of the experiments were calculated and AC Withstand criterion of dry air insulation for the AC voltage test was derived. Using the criterion, dry air gases can be used instead of the SF? gas was confirmed in the factory acceptance test at 170[㎸] GIB.