A modified self-powered wireless temperature measurement system for high voltage switchgear

Online monitoring system is the reliable and stable operation guarantee of power system, where the temperature monitoring is one of important parts. In order to meet the requirements of temperature measurement and special installation position in high voltage switchgear, a modified self-powered wireless temperature measurement system powered by a compact Current Transformer (CT) is presented in this paper. A supercapacitor and a Zener diode are used to reduce the degree of core saturation of CT and improve the maximum of busbar current that the terminal can work. A reset control circuit is adopted to start-up the terminal. The terminal operates in low power mode to minimize the start-up current. Experimental results indicate that, when the busbar current varies in the range of 30A-1400A, the wireless temperature measurement system works stably, and temperature data can be reliably obtained.