Analyses of partial discharges in dielectric samples under DC excitation

The main focus of the paper is to develop a better understanding of partial discharges under DC excitation. Partial discharges studied will initially be limited to discharges from well-defined discharge sites. These include corona, surface discharges and internal voids. The samples are first tested under AC excitation as a sense check to ensure the samples yield the expected PD events. The samples were then subjected to DC excitations where the PD events were recorded and subsequently analysed. A number of analysis techniques will be applied to potentially enable the identification and classification of the type of PD event occurring in the DC system under investigation.