Study on Electromagnetic-Thermal Simulation of 10kV Air Insulated Switchgear

In recent years, 10kV air-insulated switchgear is gradually replacing SF6 gas-insulated switchgear. In the long-term operation of the air insulated switchgear, high temperature will lead to the aging of the insulator and mechanism, resulting in serious consequences. Therefore, it is of great significance to study the temperature rise characteristics of 10kV air-insulated switchgear in different states for the promotion of air-insulated switchgear and the safe operation of power grid. In this paper, the electromagnetic and thermal coupling simulation model is established by using the multi-physical field finite element software COMSOL, and the temperature rise characteristics under normal conditions are analyzed. Then the influence of the contact resistance of circuit breaker on the temperature rise inside the switchgear is analyzed. It is found that the overall temperature rise of the A-phase conductor circuit is slightly higher than that of the other two phases. Under normal operation, the temperature rise of the lower busbar in the phase A is the highest. The increase in contact resistance caused by long-term operation will lead to an increase in temperature rise. If the contact resistance is greater than 337.5μΩ, the temperature rise of the vacuum circuit breaker contact is higher than that of the lower busbar in the phase A. The influence of the contact resistance on temperature rise is linear.