Permanent Magnet Overhang Effect on the Characteristics in Brushless DC Motor

브러시리스 직류전동기 특성에 대한 영구자석 오버행 효과

  • 전연도 (한양대 BK21기계분야) ;
  • 약미진치 (일본 조도전대학 이공학부 전기.정보생명공학과) ;
  • 이주 (한양대 전기공학과)
  • Published : 2004.04.01

Abstract

In this paper, the effect of permanent magnet overhang structure on the characteristics in Brushless DC motor has analyzed quantitatively. We classified the overhang structure as symmetric and asymmetric. 3D equivalent magnetic circuit network (EMCN) method which uses the permeance as the distributive variable is used for the efficient analysis of magnetic field. The overhang effect which increases the linkage flux at the stator is verified by comparison between overhang and no overhang structure. In addition, it is known that no load back electro motive force (EMF) is also increased due to the overhang effect. In case of asymmetric overhang structure, the ratio effect of the upper to lower overhang length on the magnetic forces is analyzed. Form the analysis results, the variation of the asymmetric overhang ratio has a significant effect on the axial magnetic force except the radial and tangential magnetic forces. The validity of the analysis results is also clarified by comparison between calculated results and measured ones such as back EMF and cogging torque.

Keywords

References

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