Dynamic modeling of the temporal evolution of DC flashover discharge current with liquid electrolyte and ice pollution layer

A dynamic model for predicting dc flashover discharge current behavior of electrolyte and ice covered insulating surfaces is presented. The model takes into consideration insulating geometry, pre-contamination level, electrical field on the front of discharge and characteristics of pollution. Assuming discharge behavior as a time dependant resistance, it is possible to determine leakage currents characteristics and time of flashover using Hampton criteria for propagating of discharge and Rumeli criteria for estimating the displacement of the discharge assuming that the electrical breakdown stress on the front of discharge will be determined by the streamer criteria. The simulated results show that the model is in agreement with experimental results and is more appropriate for high resistance of pollution for electrolyte and ice layer.