Material Dependent Partial Discharge Behaviour: A Computational Approach for HV System Design

Abstract

Partial discharge (PD) is an electrical discharge that occurs when a small area of insulation in a high-voltage (HV) environment cannot withstand the electric field and this phenomenon arises from defects such as air voids in the insulation material. This study addresses a gap in the existing literature concerning the comparative PD behaviour across different insulation types under uniform simulation conditions. Utilizing COMSOL Multiphysics, the research effectively simulated electric field distributions and estimate the partial discharge inception voltage (PDIV) for three insulation material including air, mineral oil, and epoxy resin. The result show that air exhibits the lowest PDIV (11.5kV), followed by mineral oil (28kV) and epoxy resin (57kV) confirming that materials with lower permittivity initiate discharge earlier due to higher localized field intensification. These comparative findings highlight the strong influence of dielectric properties on PD initiation and provide a computational foundation to enhance HV insulation design, material selection, and predictive maintenance practices in electric power systems.