Analysis of electric field in the inter phases region of three-phase gas insulated switchgear

This paper deals with electric field characteristics in the inter-phases region of three-phase gas insulated switchgear (GIS). The electric field in a three-phase construction of a simplified GIS model was analyzed. The results show that in the inter-phases region the direction and the magnitude of electric field vector varies with the location of the observation point while in the phase-enclosure region the direction of the electric field vector tends to linear and constant. There is no zero electric field on the particle tip of a particle in the inter-phases region, except S90 particle. There is zero electric field on the particle tip of a particle in the phase-enclosure region every half cycle of applied voltage. The maximum electric field of the particles on the interphases region generally is higher than one of the particles on the phase-enclosure region. The electric field vector locus in the inter-phases region varies: linear, elliptic, or circular while one in phase-enclosure region is constant and linear.