35 / 2024-07-12 17:47:17

Torque Optimization of Six-Phase Arcuate Sine + Third Harmonic Shaping Surface Permanent-Magnet Synchronous Motor

SPSM, parallel magnetization, Sine+3rd shaping, torque optimization

3.Electric Machine Design and Control > 1.Electric machine designs

 To increase the torque density of direct-drive surface permanent-magnet synchronous motors (SPSMs), the model of arcuate sine + third harmonic (3rd) shaping SPSM with parallel magnetization and the optimal 3rd current when the machine loaded with Sine+3rd current are derived. The finite-element (FE) models of six-phase arcuate Sine+3rd shaping and sine shaping SPSMs are established based on the principle of the same maximum permanent-magnet (PM) thickness, and their air-gap flux densities under no-load are compared. The Sine+3rd current and sine current are applied to the Sine+3rd shaping and sine shaping motors, respectively, based on the principle of equal current amplitude. The results show that the amplitude of air-gap flux density fundamental wave under no load condition of the Sine shaping SPSM is significantly lower than that of the Sine+3rd shaping SPSM, and the amplitude of other higher harmonics is unchanged except for the third harmonic. When a rated load is applied, the average torque of the Sine+3rd shaping SPSM loaded with Sine+3rd current is increased by 17.5% compared with the Sine+3rd shaping SPSM which is only loaded with the sine current mentioned above, and is increased by 26.5% compared with the sine shaping motor. The result is consistent with the theoretical calculation and provides theoretical guidance for torque optimization of direct-drive SPSMs.