Torque ripple reduction in brushless DC motor velocity control systems using a cascade modified model reference compensator

A cascade compensator is proposed for a brushless DC motor velocity control system. The compensator derives a correction signal from the inverse or the difference of the Park´s transform of the original control signal in such a way that the torque ripple from the motor is reduced. This compensator is simple; however, in digital implementation, it is with a minimum computational cost. Computer simulation results had shown a noticeable reduction in torque ripples as compared to cases without the compensator