Modified E-field analysis around spacers in SF6 GIS under DC voltages

In the case of DCGIS, charges invariably accumulate over a period of time along the spacer surface. Again, the electric field distribution around solid spacer is greatly altered by the accumulated surface charges. The breakdown strength of SF₆ gas is badly affected by locally enhanced electric field. Metal insert electrodes, which are used in GIS, reduce stresses near the triple junctions with simultaneous rise in the stresses elsewhere along the spacer surface. In this paper, the E-field distribution around two types of spacer configuration without and with metal insert electrodes have been studied. Effects of various parameters on the surface charge modified E-field have also been studied and presented