Comparative Analysis of Dual-Stator Permanent Magnet Machines with Inner Stator Teeth Designed in Hypotenuse for Electric Vehicle

The paper designs and analyzes new dual-stator permanent magnet machines with inner stator teeth designed in hypotenuse (ISTH-DSPMM), which can be applied in electric vehicle requiring high torque quality. The IST with hypotenuse can function as modulator to regulate the airgap flux density, which can effectively suppress the harmonic distortion to achieve low harmonic distortion and low torque ripple. The designed IST are combined of rectangle and triangle, which can be formed as trapezoid- and parallelogram-shaped stator teeth. Three representative ISTH-DSPMM and the conventional DSPMM with rectangle inner stator teeth are comparatively analyzed using method of finite element analysis (FEA). The investigated four machines have identical key parameters except the shape of IST for a fair comparison. The FEA-calculated results including back electromotive force, steady torque at rated state and torque ripple verify the merits of designed ISTH-DSPMMs.