Analysis of the Effect of Permanent Magnet Width on Cogging Torque of Interior LSPMSM

https://doi.org/10.5614/j.eng.technol.sci.2026.58.5.8

Authors

  • Tuan Anh Le Faculty of Energy Engineering, School of Electrical and Electronic Engineering, Hanoi University of Industry, No. 298 Cau Dien Street, Tay Tuu Ward, Hano, 100000,
  • Nhu Y Do Faculty of Electromechanics, Hanoi University of Mining and Geology, No.18 Vien Street - Dong Ngac Ward - Ha Noi, 100000 https://orcid.org/0000-0001-6395-2875
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Abstract

The line-start synchronous permanent magnet synchronous motors have the advantages of high efficiency and line-starting capability. However, this type of motor has the drawback of high cogging torque, which is the main cause of vibration and noise during operation. Analyzing the factors affecting cogging torque is essential and important in the design of these motors. This paper studies the impact of magnet width on cogging torque. Theoretical analysis and finite element method simulations for the test motor show that the cogging torque can be significantly high, reaching up to 5% of the rated torque of the motor. Research results indicate that cogging torque can be reduced by decreasing the width of the permanent magnet. However, reducing the magnet width adversely affects the startup characteristics, torque, and efficiency of the motor, demonstrating the existence of an optimal width that balances cogging torque and other parameters in motor design. Additionally, the research results have been validated through experimental modeling, showing a close correlation in the shape of the cogging torque and the back eletromotive force characteristics, with a small error of less than 5%.

How to Cite

Tuan Anh Le, Nhu Y Do (2026). Analysis of the Effect of Permanent Magnet Width on Cogging Torque of Interior LSPMSM. Journal of Engineering and Technological Sciences, Vol. 58 No. 5 (2026): Vol. 58 No. 5(2026): October, 697-713. https://doi.org/10.5614/j.eng.technol.sci.2026.58.5.8

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Date Log

Submitted
April 22, 2025
Accepted
July 22, 2026
Published
September 2, 2026

Keywords

  • cogging torque
  • electric motor
  • line-start permanent magnet synchronous motor
  • permanent magnet
  • permanent magnet synchronous motor

Issue

Vol. 58 No. 5 (2026): Vol. 58 No. 5(2026): October

Section

Articles

How to Cite

Analysis of the Effect of Permanent Magnet Width on Cogging Torque of Interior LSPMSM. (2026). Journal of Engineering and Technological Sciences, 58(5), 697-713. https://doi.org/10.5614/j.eng.technol.sci.2026.58.5.8

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