Transfer function modeling of partial discharge behavior evolved during application of a time varying power frequency voltage

In this work, an attempt has been made to model the relationship between the amplitude of a 60Hz voltage applied in a step fashion to a rod-plane Gap with a dielectric barrier (a nanofilled polypropylene film affixed to ground plane) and the resulting partial discharge quantities. The applied voltage sampled at discrete time intervals is considered as input and corresponding partial discharges sampled at equispaced times as output resulting in a bivariate stochastic process. The main field is controlled by a programmable logic controller programmed autotransformer and the PD behavior is dependent on the combined effect of variations in main field and the field due to residual charges from earlier partial discharges. The experimental results are analyzed through a transfer function model. The details of the steps involved in the modeling process are discussed and results are presented.