Research on Online Temperature Monitoring System Based on SAW for Intelligent Circuit Breaker

Composed by data acquisition unit, intelligent identification unit and regulating unit, intelligent circuit breaker (ICB) plays a critical role in intelligent substations, which cuts off the fault line in a quick and accurate way when fault occurs, to ensure the stable operation of intelligent substations. Temperature is the important characteristic embodying the operating status of ICB. Aiming at the difficulty of collecting temperature data in ICB, the surface acoustic wave (SAW) based online temperature monitoring system of ICB is designed. The COMSOL software is utilized to conduct research on the temperature field distribution in ICB, the position of overheating fault is determined, and it provide theoretical basis for the intelligent identification of temperature data in the breaker. The SAW temperature sensor conducts acousticelectric signal conversion through its piezoelectric substrate, uses the changes of the transmission frequency of the SAW to reflect the changes of temperature. So the accurate collection of temperature data in ICB is ensured. This system has characteristics of strong anti-interference capacity, high transmission speed and high accuracy.