Torque Ripple-Minimizing Control of IPMSM With Optimized Current Trajectory

In an interior permanent-magnet synchronous machine (IPMSM) for higher torque density, there would be undesirable torque ripples due to spatial harmonics. This article analyzes the torque ripple based on the actual torque map, which is more practical and accurate than the torque model-based analyses. Based on the analysis, a torque ripple-minimizing scheme is proposed for practical IPMSMs. In addition, an experimental identification method of torque map is proposed. The identified torque map is used not only for the proposed torque ripple-minimizing method, but also for the torque reconstruction in experiments. Simulation and experimental results are provided to verify the proposed method. It is confirmed that the harmonic torque ripple under target has been reduced by over 90%.