Instantaneous Torque Control of Switched Reluctance Motor Based on Novel Reaching Law and Disturbance Observer
Aiming at the traditional control strategy of switched reluctance motor which is prone to large torque pulsation and poor dynamic performance,an instantaneous torque control based on adaptive convergence law and disturbance observer was proposed.First,a demagnetization signal was added to the hysteresis loop strategy in order to avoid torque overshoot when the rotor enters the unidirectional conduction interval.Second,a non-sin-gular fast terminal sliding mode function was proposed by combining the linear and terminal sliding mode sur-faces to realize the fast convergence of the system in both reaching and sliding phases.Subsequently,an adaptive convergence law and a segmented switching function are designed to solve the convergence speed and chattering problems in the traditional reaching law,and in order to reduce the switching gain,a sliding-mode disturbance observer was used to feed forward the external perturbation to the controller in time.Finally,a 6/20 motor was simulated and experimentally verified,and the results showed that the new hysteresis strategy could effectively reduce the torque ripple,and compared with the PI and the traditional sliding mode control,the improved sliding mode method not only realized the speed without overshooting and shortens the dynamic response time,but also strengthens the anti-disturbance performance of the motor,and the output torque ripple was further reduced.