Research on Cosine-Type Non-uniform Air Gap Structure Based on Finite Element Analysis

  • Yuanyuan YangEmail author
  • Bulai Wang
  • Xiutao Ji
  • Xiangsheng Liu
  • Qiangqiang Xu
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 528)


That the air gap magnetic field of PMSM contains a large number of harmonics, aiming at the problem, this paper presents a cosine-type non-uniform air gap motor structure. Taking a 22 kW 3000 rpm permanent magnet synchronous motor as the researching object, a motor model was established by finite element analysis software to calculate the air gap flux density, no-load back EMF and output torque distribution curve respectively. The comparing results prove that the cosine type non-uniform air gap structure can effectively reduce the no-load back EMF harmonic components, reduce the torque ripple and improve the motor efficiency.


Cosine-type non-uniform air gap MagneForce No-load back EMF Torque ripple 


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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Yuanyuan Yang
    • 1
    Email author
  • Bulai Wang
    • 1
  • Xiutao Ji
    • 1
  • Xiangsheng Liu
    • 1
  • Qiangqiang Xu
    • 1
  1. 1.School of Electrical and Electronic EngineeringShanghai Institute of TechnologyShanghaiChina

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