Braking torque closed-loop control system and method for switch reluctance motor

摘要

A braking torque closed-loop control system and method for switch reluctance motor belong to motor braking closed-loop control systems and methods. The closed-loop control system is composed of a torque regulator, a mode selector, a current regulator, an angle optimization controller and a torque estimator. The braking torque closed-loop control is adopted by the whole system. On the basis of the rotating speed of the motor, the mode selector selects an implementation of phase current soft chopper control in a low rotating speed region and an implementation of angle position control in a high rotating speed region. The current regulator performs soft chopper hysteretic current regulation. The angle optimization controller optimizes a turn-on angle and a turn-off angle of a power converter master switch to reduce torque pulsation and improve braking energy feedback efficiency. The torque estimator conducts on-line estimation of an actual braking torque estimated value of the switch reluctance motor on the basis of an actual phase voltage and an actual phase current of the motor to achieve braking torque signal feedback. The method has advantages of low switching frequency, small switching loss, fast braking torque response, high braking torque control accuracy, small braking torque pulsation, and high energy feedback efficiency.