고체절연물의 연면절연파괴특성 평가

Assess a Breakdown Characteristics of Solid Dielectrics Surface Discharge Characteristics

This paper gives a basic data of the stnface discharge characreristics for solid Dielectrics in Dry-Air & SF₆ Used electrodes are needle to plane, sphere to plane and KS M3015 electrodes. Also, this paper describes the fundamental surface discharge characreristics of solid dielectric under Sphere-Plane field in insulation dielectric gases. SF₆ as conventional gas in Gas Insulared Switchgear(GIS) and environmentally friendly gases; Dry-Air are used in the same experimental conditions. Breakdown voltage and dielectric strength are found out and sorted. These results are getting higher as increasing the gas pressure acccrding to the medium effect The medium effect by the gas pressure and the gap can be explained by surface roughness of a solid dielectric and an electrode as well as an electric field which decreases due to the correlation between the collision ionization coefficient and the gap, respectively. By researching the increasing rates of breakdown voltage as following the solid dielectric thickness, it reveals that the thickness also affects the breakdown voltage. Finally, through comparing and corresponding between SF₆ and Dry-Air the possibility of replacement of SF₆ by environmentally friendly gas is proved.