Charge injection in gold ground electrode corona charged polyethylene film: Numerical simulation on surface potential decay

Surface potential decay measurement is a simple and low cost tool to examine electrical properties of insulation materials. Bipolar charge injection has been verified by the measurement of space charge in the corona-charged sample using the pulsed electro-acoustic method (PEA). Over the years, various models have been proposed to describe charge transport within the material and one common feature in these models is that they were all based on single charge injection from the charged surface. A new model based on a bipolar charge injection has been proposed recently. In the present paper, numerical simulations have been carried out using the model and results have been compared with surface potential decays obtained from 50μm low density polyethylene films and gold coating sample after corona charged and PEA measurements. The simulation results show that several features experimentally observed can be readily revealed.