Optimization of Small Layer with Conductivity on Cone Type GIS Spacer Surface for Relaxation of Electric Field

For compact design of HV-GIS, the maximum electric field stress should be relaxed as much as possible. Especially, in general, the electric field distribution around GIS solid spacer becomes critical for electrical insulation performance. For the electric field relaxation, various kinds of techniques have been reported. In this paper, we examine the applicability of the small layer with conductivity on the spacer surface for the electric field relaxation from the results of the finite element simulation. In the numerical simulation, we give the thin layer around the triple junction of GIS spacer. Then, we obtain the electric field distribution with or without the conductive layer on the spacer surface. As the design parameters of the conductive layer, we choose the conductivity of the…