Additional Cogging Torque Components in Permanent-Magnet Motors Due to Manufacturing Imperfections

This paper presents issues for reducing cogging torque of permanent-magnet motors. When proper methods are employed, it is theoretically possible to minimize its level or even to eliminate it. FFT analyses of cogging torque in mass-produced motors have shown additional harmonic components, which are in tight correlation with assembly tolerances and/or permanent-magnet imperfections. Finite element method has been used to study the sensitivity of different motor models relative to manufacturing tolerances and to determine rules for detecting imperfections in mass-production.

[1]  T. Sebastian,et al.  Issues in reducing the cogging torque of mass-produced permanent-magnet brushless DC motor , 2004 .

[2]  T.J.E. Miller,et al.  Assessment of torque components in brushless permanent magnet machines through numerical analysis of the electromagnetic field , 2004, Conference Record of the 2004 IEEE Industry Applications Conference, 2004. 39th IAS Annual Meeting..

[3]  Nicola Bianchi,et al.  Design techniques for reducing the cogging torque in surface-mounted PM motors , 2000, Conference Record of the 2000 IEEE Industry Applications Conference. Thirty-Fifth IAS Annual Meeting and World Conference on Industrial Applications of Electrical Energy (Cat. No.00CH37129).

[4]  R. Fiser,et al.  Detection and FEM Analysis of Additional Cogging Torque Components in PM Motors , 2008 .

[5]  Ki Jin Han,et al.  Optimal core shape design for cogging torque reduction of brushless DC motor using genetic algorithm , 2000 .