Study of the Reduction of Torque Ripples for Multi-pole Interior Permanent Magnet Synchronous Motors using Rotor Saliency

회전자 돌극 설계를 이용한 다극 매입형 영구자석 동기전동기의 토크리플 저감 연구

  • Kim, Ki-Chan (Department of Electrical Engineering, Hanbat National University)
  • 김기찬 (한밭대학교 전기공학과)
  • Received : 2014.07.10
  • Accepted : 2014.10.10
  • Published : 2014.10.31


The paper reports an improvement method on torque ripples of multi-pole interior permanent magnet synchronous motor (IPMSM) applied to a traction motor for hybrid electric vehicles. In the case of multi-pole IPMSM, the magnetic flux generated by a permanent magnet tends to leak through the bridge of the rotor without a link with stator windings. The slit design on the rotor surface was proposed to reduce torque rippling and increase the output power by reducing the leakage flux. Two design parameters for the slit are suggested for optimal design using the response surface method. As an analysis method, the 2D finite element method (FEM) was applied to consider magnetic saturation effect.


Interior permanent magnet synchronous motor;Response surface methodology;Torque ripple reduction


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