Abstract: Excessive contact temperature can directly affect the performance of vacuum circuit breakers, reducing their opening and closing speed and insulation performance, which in tum leads to an increase in the failure rate of vacuum circuit breakers. Therefore, in response to the difficulty of monitoring the temperature rise of contacts in vacuum environments, this study proposed a method for measuring the temperature of contacts in the arc extinguishing chamber for high-voltage vacuum circuit breakers. Firstly, we used an infrared thermometer to monitor the current contact temperature in the arc extinguishing chamber of the high-voltage vacuum circuit breaker, and then corrected the infrared temperature based on the environmental temperature measured by emissivity and fiber Bragg grating temperature sensors. Then, we established a mathematical model for the dynamic temperature rise of the contact, and ANSYS Workbench simulation software was used to perform multiphysics field coupling solution to obtain simulation results, such as the contact temperature distribution and temperature rise rate. The results show that, with the increase of time, the temperature measurement error of the studied method does not show a significant increasing trend, indicating that the method can maintain high stability and accuracy in the long-term temperature measurement process.

Key words: vacuum circuit breaker, vacuum arc extinguishing chamber, contact temperature rise, non contact temperature measurement