Torque Ripple Reduction of IPMSM Considering Compensation of Nonlinearities of Magnetic Characteristics

This paper proposes a torque ripple estimation and reduction of IPMSM with concentrated winding considering nonlinearity of magnetization characteristics. First, the proposed torque ripple estimation method which ignores nonlinearities such as magnetic saturation and cross-coupling is derived and some problems of this approach are presented. Then, the torque ripple estimation method considering nonlinearity of magnetization characteristics is proposed, in which this approach is based on simple approximations of the magnetization curve. After that, a torque ripple reduction is proposed, which are based on the adaptive identification of the equivalent torque coefficient. Finally, the performance of the proposed method is experimentally evaluated to show the feasibility of the proposed method.