Partial Discharge Activity in Polymeric Cable Insulation under High Voltage AC and DC

The focus of this paper is to report on analysis of partial discharge characteristics in insulation samples containing artificially created voids under AC and DC excitation. Samples were initially tested under AC conditions to determine that the artificial void was the dominant source of PD. Once this was proven the samples were tested under DC to generate knowledge on PD under these conditions. The results were analyzed, with differences between AC and DC PD in artificial voids determined. The impact of these differences on potential methods of PD detection are also briefly discussed.