A Novel Method to Reduce of Cogging Force in a Linear Flux-Switching Permanent Magnet Brushless AC Machine

  • Gaojun MengEmail author
  • Ye Yuan
  • Yukun Sun
  • Haitao Liu
  • Zhiying Zhu
Original Article


The primary linear flux-switching permanent magnet (LFSPM) motor has the merits of high speed, high response, and direct drive. However, the presence of the cogging force in LFSPM motors compromises position and speed control accuracy, which can be particularly troublesome at low speeds. A novel approach of suppressing the slot effect cogging force for LFSPM is proposed according to repetitive control of time-varying periodic signals. The time-varying periodic thrust disturbance in t-domain is transformed to the signals defined in the x-domain, and a repetitive controller is designed. Furthermore, a series of specific harmonic currents are added into q-axis reference current, resulting in additional force components to counteract the end effect cogging force. Finally, experimental evaluations of the control strategy are performed on an AD5435-controlled LFSPM drive platform. The simulations and experiments verify that the proposed method can suppress the thrust ripple effectively.


Permanent magnet linear flux-switching permanent magnet (LFSPM) Permanent magnet (LFSPM) Cogging force Time-varying signals x-Domain repetitive controller Harmonic currents 



This paper is supported in part by grants from the National Natural Science Foundation of China (Project No. 51507077,51877101,51707082), The China Postdoctoral Science Foundation funded project (Project No. 2018M632201) and the Open Research Fund of Jiangsu Collaborative Innovation Center for Smart Distribution Network, Nanjing Institute of Technology (Project No. XTCX201702), and talent start fund (Project No. YKJ201713).


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Copyright information

© The Korean Institute of Electrical Engineers 2019

Authors and Affiliations

  • Gaojun Meng
    • 1
    Email author
  • Ye Yuan
    • 2
  • Yukun Sun
    • 1
  • Haitao Liu
    • 1
  • Zhiying Zhu
    • 1
  1. 1.Department of Electric Power EngineeringNanjing Institute of TechnologyNanjingChina
  2. 2.Department of Electrical and Information EngineeringJiangsu UniversityZhenjiangChina

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