The Effect of Micro Discharge on the Time Characteristics of Surface Charge Accumulation in DC-GIL

In the DC GIL, the accumulation of surface charges could cause electric field distortion and thus even cause the flashover. In the numerical simulation of surface charge accumulation, only the charge carriers generated by natural ionization are considered in some of the studies. But in fact, during the operation of DC GIL, due to the rough surface of the insulator and other reasons, weak discharges always exist. These weak discharges are called micro discharges. In this paper, the micro discharge on the surface of the insulator is modeled, and the influence of the micro discharge on the surface charge accumulation time characteristics of the DC basin insulator is studied. The simulation results show that the existence of micro discharge will shorten the time constant for surface charge accumulation.