Investigation on Electromagnetic Torque of a Flux-Switching Permanent Magnet Motor From Perspective of Flux Density Harmonic Reduction Ratio

This article proposes a method to improve the electromagnetic torque of the I-shaped flux-switching permanent magnet (FSPM) motor considering the flux density harmonic reduction ratio. First, based on the harmonic torque contribution, the harmonics for research are selected. The corresponding flux density harmonic reduction ratio is calculated by comparing the flux density of the rotor yoke with the air gap side. Then, the comprehensive reduction ratio incorporating the selected harmonics is further obtained. Moreover, the FSPM motor is optimized for the reduction ratio and the electromagnetic torque. The characteristics related to the flux density harmonic reduction ratio and other basic performances are evaluated, including magnetic field and flux distribution, no-load back-electromotive force, and so on. Finally, the simulation results verify the effectiveness and rationality of the reduction ratio method. It reveals that the proposed method of the flux density harmonic reduction ratio offers a new perspective to analyze and improve the output performances of the FSPM motor.