Effect of charge accumulation on the electric field distribution along spacer surfaces

The effects of surface charge accumulation on electric field distribution around solid spacers bridging the uniform field gap stressed with DC voltage relevant to DC gas-insulated substations (GIS) have been studied numerically by the charge simulation method. The numerical evaluations of charge accumulation are found to agree with experimental data reported by other researchers. The present work reports on an analysis of resultant stress distribution on a few spacer configurations for which accumulated surface charges modify the electric field and, for a certain case study, charge accumulation has resulted in reduced resultant peak stress