Investigation of Charged Particles Motion Behavior During Partial Discharge in Hemispherical Voids at Epoxy/Metal Interface Via Modeling and Experiment

This article establishes a numerical model of partial discharge in epoxy resin/metal interface hemispherical voids using drift diffusion equation, studies the physical process of partial discharge in voids of different sizes, and verifies the effectiveness of the model through experiments. Both experimental and computational results indicate that larger sized gaps have higher partial discharge initiation voltage and discharge capacity, and the distribution of different types of charged particles is not the same. The simulation results reveal from a microscopic perspective that positive ions exhibit periodic distribution before discharge, while electrons and negative ions only undergo significant changes in distribution during discharge. This model is closer to the actual interface defect morphology and helps to deepen the understanding of this type of partial discharge phenomenon.