Abstract Permanent magnet synchronous motor (PMSM) is applied in high performance control systems more and more widely, but the cogging torque will affect the control precision of the system. A novel method of combining different permanent magnets (PMs) in axial direction is proposed for reducing cogging torque in this paper. The expression of cogging torque was analyzed based on energy method and Fourier decomposition method, and the size of combined PMs can be deduced according to the formula. Finite element method (FEM) was used to verify the effectiveness of the method, and the optimal combination was derived. The air-gap flux density and PM consumption of the optimal combination were compared with the original motor. The proposed method was verified to be economic and effective. Finally, other performance of the proposed motor was analyzed, including the harmonic contents of the back-EMF. It is concluded that the new rotor proposed can improve the performance of the motor.
Bao Xiaohua,Wu Changjiang,Fang Jinlong. Cogging Torque Reduction in Surface-Mounted Permanent Magnet Synchronous Motor by Combining Different Permanent Magnets in Axial Direction[J]. Transactions of China Electrotechnical Society, 2018, 33(18): 4231-4238.
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2018, Vol. 33 
