Simulating partial discharge activity in a cylindrical void using a model of plasma dynamics

Partial discharge (PD) activity models typically use simplified descriptions of individual discharges to develop a model of discharge activity. This approach neglects the plasma dynamics of the discharge, and requires the use of multiple assumptions. In this work, plasma dynamic simulations of individual PDs are used to inform a PD activity model for discharges within a cylindrical cavity bounded by low density polyethylene. Specifically, by considering the plasma dynamics of the discharges it is possible to determine: surface charge density distributions, apparent charges, the inception electric field and the residual electric field. The resulting PD activity model had only a single adjustable parameter, relating to the availability of seed charges, and was able to produce phase resolved PD patterns that were comparable with experimental data. Good agreement was also observed between the measured and simulated PD extinction voltage. The shortcomings of PD activity models are discussed including the poor understanding of the seed charge generation rate. Nevertheless, the model does allow robust conclusions on the PD dynamics in the experiment. The main contribution of this work is to show how simulations of plasma dynamics can be used to provide additional insight PD activity.