Suppression of Torque Ripple of a Flux-Switching Permanent Magnet Motor in Perspective of Flux-Modulation Principle

In this article, the suppression mechanism of torque ripple for the flux-switching permanent magnet (FSPM) motor is investigated. According to the flux modulation principle, the generation principle of torque harmonics is analyzed, which is generated by the interaction between the radial and tangential airgap harmonics. Based on the analysis, a method to suppress the torque ripple of the FSPM motor is proposed, where the airgap harmonics are newly applied to be the bridge to establish the relationship among torque ripple, torque harmonic components, and key design parameters. To confirm the effectiveness of the proposed method, an FSPM motor with the V-shape permanent magnet (VS-FSPM) motor is selected as the research example. The leading torque harmonics and leading airgap harmonics of the VS-FSPM motor are picked out effectively. Some key design parameters are selected according to the flux modulation principle to improve the leading airgap harmonics and reduce the corresponding torque ripple successively. Furthermore, the torque ripples of the initial and improved VS-FSPM motor are calculated and compared in detail. Finally, a prototype motor is built and tested. Both the theoretical analysis and experimental results verify the effectiveness of the proposed new method.