Torque ripple reduction of brushless DC motor based on optimal control with adaptive compensation

The inherent torque ripple of brushless DC motor limited its scope of application. In this paper, the state space model of system was derived from the mathematical model of motor to generate the desired current. An optimal state feedback controller using the Kalman filter state estimation technique was established aimed at ripple free torque control. An active disturbance rejection control algorithm was proposed to compensate for the effects of input disturbance. Experimental results are presented that these two algorithms working together are capable of reducing the torque ripple effectively under the condition of constant torque load.