Research on Intelligent Control Technology for Motor Operating Mechanism Applied to Vacuum Circuit Breakers

In order to improve the mechanical impact caused by contact collision and spring bounce during the closing process of circuit breakers, a segmented fixed duty cycle control strategy based on PWM control is proposed to segment control the motion process of the moving contacts of the circuit breaker. This article focuses on the design of a control device for the motor operating mechanism of a 126kV vacuum circuit breaker. A segmented duty cycle control strategy is adopted to complete the closing operation of the circuit breaker. Four control strategies are developed through theoretical analysis, and the response time and opening and closing time are compared through simulation verification and online testing. The experimental results show that during the open distance stage, the control strategy of strategy 3, which adopts full voltage starting, reduces the duty cycle before the close point and increases the duty cycle after contact, can shorten the response time and improve the closing speed, and alleviate the mechanical collision problem between contacts.