Radiation spectra of partial discharge in dielectrics

Partial discharge is the precursor of the insulator breakdown. The radiation pattern of partial discharge in dielectrics is investigated. It is envisaged that knowing the spectra of radiation emitted from dielectric cavities under electrical stress can be beneficial in designing partial discharge sensors. The radiation pattern is dependent on a multitude of parameters. Among these, the intensity of the source as well as the dielectric material and its geometry are the main parameters. We have investigated the radiation pattern in three common dielectrics used in power industry: polymer, epoxy resin and ceramics.