Tracking Control of Vacuum Circuit Breaker Based on a Control Law with Nonlinear Correction Function

For phase-controlled vacuum breakers, the acting time of Permanent Magnetic Actuator (PMA) should be precise. Variation of capacitor voltage, jamming, temperature, etc. (called disturbance factors) impact dispersion of closing time seriously. Tracking control is used to suppress this dispersion. However, PMA is a nonlinear, high-order complex system. The control process is dynamic following control. Therefore, the dispersion suppression capability of conventional controllers faces challenges. In order to solve this problem, a new technology has been put forward in this paper. By using this technology, response speed and anti-interference ability of the control system are improved. Time scatter is better suppressed. A current-displacement double closed-loop controller (CDCC) based on inverse system method is proposed. During the motion stage, the dynamic characteristics of the controller can be optimized by using the inverse systems to correct output of the automatic displacement regulator (ADR) and the automatic current regulator (ACR). A simulation system is established and performance of different control methods commonly used in phase control is compared. Based on the aforementioned theory, many experiments have been performed when disturbance factors change, such as capacitor voltage, environment temperature, and so on. Results prove that current deviation and displacement deviation can be corrected under severe conditions and closing time can be stabilized within ±0.5 ms. Therefore, anti-interference ability and dynamic performance of PMA are ensured when external factors change drastically, which will increase accuracy of the phase-controlled operation and prolong the lifespan of circuit breakers.