The purpose of this study is to propose an innovative Halbach permanent magnet (PM) array structure with optimized iron poles to reduce the pole leakage of the consequent-pole (CP) structure, improve the output torque, and suppress the torque ripple.
First, the staggered-pole CP structure is illustrated to reduce the cogging torque and suppress the torque ripple. Second, on the basis of the staggered-pole CP structure, the three-segment double-layer Halbach consequent-pole (TDCP) structure with optimized iron poles is proposed, which is compared with the non-Halbach CP structure and traditional three-segment Halbach consequent-pole structure and the influence of iron poles change on the torque of TDCP motor is analyzed. Then, the equivalent surface current method is used to analyze the air gap magnetic field of the TDCP motor. Finally, the magnetic pole structure of the three motors is optimized by evolutionary algorithm and the electromagnetic characteristics of the three motors are compared and analyzed.
The results show that the TDCP motor with optimized iron poles has the best comprehensive performance. Compared with the CP motor, the magnetic pole leakage is reduced, the average torque is increased by 8.4%, the torque ripple is reduced by 27.7% and the silicon steel consumption in iron poles is reduced by 17%.
Compared with the existing CP motor, the magnetic pole structure proposed in this paper has higher PM utilization rate, improves the stability of the motor, reduces the cost of the motor and proposes to optimize the CP motor iron poles to improve the performance of the motor.
