Torque Ripple Suppression Control for Dual Three-Phase Permanent-Magnet Synchronous Motor

This paper proposes torque ripple suppression control for dual three-phase PM synchronous motors with 0^° shifted angle between sets. A new matrix transformation based on the relationship between variables of the d₁q₁/d₂q₂ sub-planes and the d_q/d_zq_z sub-planes is proposed and torque ripple suppression control mathods are raised based on different current control strategies used in the d_q/d_zq_z sub-planes of the new coordinate system. The open loop current control proposed in the d_zq_z sub-plane can partially suppress torque ripple of the whole system, and the PIR control in the d_zq_z sub-plane is exploited to suppress current unbalance between sets, while the additional PIR control in the d_q sub-plane is executed to attenuate the 2nd current harmonic components. Torque ripple of the whole system can be attenuated with the suppression of current unbalance between sets and the 2nd current harmonic components. The effectiveness of proposed methods is verified by a set of comparative experiments on a 3kW dual three-phase PM machine system. It shows that the 2nd harmonic torque of the whole system is attenuated compared to the dual d_q method when using above three methods, and the additional PIR control in the d_q sub-plane has the best effect on the suppression of torque ripple of the whole system.