Thermoelectric Coupled Analyses of the Thermal and Electric Fields at the Tulip Contact for a Medium-Voltage Switchgear

The key issue in thermos-electrical analysis of medium voltage switchgear is the heat due to electric contact. In this paper, a novel thermoelectric coupled model is developed for quantitative analysing the temperature field. It shows that the high temperature region located at the tulip contact due to severe contact resistance there. Due to aging of the springs used for holding the tulip contact fingers, the lacking of holding force may lead to less contact areas between the tulip fingers and the static/moving arms, which can lead to a severe increase of the contact heat generation rate. Thus, severe temperature rise may occur and lead to an overheating problem in a medium voltage switchgear. It lays solid foundation for maintaining and operating of the switchgear.