Simulation Study on Temperature Rise Characteristics of Medium Voltage Switchgear Under Fault Condition

The heating failure of medium voltage switchgear is a common problem, and it is difficult to meet the temperature rise standard under the fault condition. Therefore, it is of great significance to study the temperature rise characteristics of medium voltage switchgear under the fault state for the safe operation of power grid. Firstly, using the simulation model of electromagnetic, temperature and flow coupling with finite element simulation software, the temperature rise distribution at 1.1 times the rated current is analyzed and verified by experiments. The influence of the change of contact pressure on the temperature rise in the vacuum quench chamber and at the plum contact is simulated and analyzed respectively. The results show that the increase of contact resistance due to the decrease of contact pressure will lead to the increase of temperature rise. The closer the measuring point is to the fault point, the greater the impact on temperature rise will be. The larger the contact resistance of the fault point is, the approximate linear change of temperature rise of the temperature measuring point increases.