Factors Influencing Dielectric Performance of SF6 Insulated GIS

This paper presents a United Kingdom manufacturer's viewpoint concerning the principal factors which influence the dielectric integrity of SF6 insulated substation equipment. Breakdown performance studies have been undertaken, to obtain design data for GIS, involving SF6 and SF6/solid support insulation, under conditions using different electrode configurations for both clean and particulate contaminated systems. Selective test data is presented and discussed along with service stress levels adopted in the UK and finally, the significance of these test results on site test commissionitg procedures relevant to SF6 GIS is commented upon.