A practical method for reducing torque ripple of interior permanent magnet machine by optimizing rotor topology

This paper discusses the reduction of torque ripple in interior permanent magnet (IPM) machine. We find that the torque ripple can be minimized by optimizing two key parameters of rotor based on the principle of virtual displacement. The effectiveness of the proposed method is proved by the analytical and finite element analysis (FEA) results. Finally, a prototype was built, and the test result was compared with predicted torque waveform as a mean of confirming the model accuracy.