On the correlation between partial discharge parameters and the degradation characteristics of polyester resin insulating systems

If trends in measured discharge data can be correlated with the breakdown process then there exists a possibility for the development of on-line breakdown prediction techniques. The use of automated test and measurement allows making twelve related measurements on experimental samples as degradation `trees´ are initiated and grow to final complete breakdown of the material. Correlations between these measurements are found and conclusions are drawn with regard to the significance of certain measurements and their effectiveness for breakdown prediction. The sample material was transparent polyester resin with point-plane electrode geometry. The electrode gap was 2 mm. All experiments were conducted with the plane electrode grounded and 10 kV, 50 Hz a.c. applied to the embedded needle