Electromagnetic Torque Analysis for All-Harmonic-Torque Permanent Magnet Synchronous Motor

This paper proposed a new type of permanent magnet synchronous motor (PMSM) called all-harmonic-torque PMSM (AHT-PMSM) to enhance the electromagnetic torque by using all harmonics of the magnetomotive force. The stator windings structure, drive converter configurations, and control model of the AHT-PMSM are illustrated. The calculation process of the average electromagnetic torque (AET) and torque ripple for AHT-PMSM are also analyzed. It is demonstrated that the theoretical AET of AHT-PMSM is improved by 23% compared to that of the normal PMSM with sinusoidal (SIN-PMSM) supply. Finally, a 24-slot/4-pole AHT-PMSM and SIN-PMSM prototypes are manufactured and tested to validity the effectiveness of the torque enhancement techniques.