Effect of Surface Charge Distribution on the Electric Field in a Void due to Partial Discharges

After a partial discharge (PD) occurs within a dielectric bounded void, charge accumulation on the void surface have been found to affect the field distribution in the void. In this work, a simplified model of PD events of a spherical void within a homogeneous dielectric material has been developed using finite element analysis (FEA) software. The model has been used to study the influence of surface charge distribution on the electric field distribution in the void due to PD events. Surface charge distribution depends on charge propagation along the void surface during a PD occurrence and charge movement along the void wall through surface conduction after a PD occurs. Comparison between measurement and simulation results has been performed to validate the model