Electric field optimization on 150 kV GIS spacer by modification of spacer shape and conductor configuration

This paper deals with the electric field optimization on the spacer of ISO kV Gas Insulated Substation (GIS) by modification of spacer shape and conductor configuration. The basic spacer model has isosceles triangle configuration of conductor and contact angle 55°. There are two modifications which is done to basic spacer. The first one is changing contact angle of spacer to 75°, 60°, 45° and 30°. The other one is changing conductor configuration to equilateral triangle with distance between conductor becomes 230 mm, 250 mm, 270 mm and 290 mm. The maximum electric field intensity on ISO kV GIS spacer without modification is 138 kV/cm. The maximum electric field intensity is still below the electric field breakdown of epoxy resin (197 kV/cm). By changing the contact angle of spacer to 75°, maximum electric field on spacer is reduced to 97 kV/cm and by changing conductor configuration and distance between conductor becomes 270 mm, maximum electric field on spacer is reduced to 118 kV/cm.