Torque ripple compensation in permanent magnet synchronous motors based on Kalman filter

This paper presents a scheme for compensation of the electromagnetic torque ripple in field oriented control of nonsinusoidal permanent magnet synchronous motors. The stator flux linkage produced by the magnets is modelled as the sum of two terms, the first accounting for the 1^st spatial harmonic component and the second for the residual high order harmonics. The sources of torque ripple, due to the harmonics term, are identified by a Kalman filter and used to compensate the torque current reference generated by a speed controller. The reduction of the torque pulsation obtained by the method and the sensitivity with respect to the variation of the motor parameters are presented and discussed by means of realistic simulations