Partial Discharge Inception Voltage under Inverter Surge Voltage Considering Interactive Effects of Environmental Factors

Abstract

Effects of environmental factors on partial discharge inception voltage (PDIV) under inverter surge voltage was discussed with multiple regression analysis in this study. As the environmental factors, humidity, temperature, and pressure were taken into account. These factors can change in high-voltage motors used for actual vehicles. The PDIV under a surge voltage showed different changes from that under sinusoidal voltage due to variation of initial electron generation probability depending on environmental change. Our results revealed that humidity has a significant effect on the PDIV under surge voltage, and there are interactive effects between humidity and temperature, and humidity and pressure. We discussed the effect of humidity and these interactions in terms of the generation of initial electrons from the air and verified this by measuring the density of negative ions in the air.