Analytical Analysis of Cogging Torque in Motors of Permanent MagneticType

영구자석을 사용한 모터의 코깅토크에 관한 이론적 해석

Go, Hong-Seok;Kim, Gwang-Jun

  • Published : 2000.07.01


One of the principal sources of vibration and noise in permanent magnetic machines is cogging torque, which is induced by interaction between the rotor poles and the stator teeth. For its analysis, using finite element analysis is very time consuming and the calculation of performance factors is extremely sensitive to the discretization. Especially, Maxwell stress tensor method is sensitive to the location of integral path. In this paper, a cogging permeance fuction is defined and replaced by the straight line. And it is assumed that the flux density acting on the stator's tooth side is the euqal to the flux density of the slot area. Using this definition and assumption, analytical calculation of cogging torque is presented and validated. And several reduction method is introduced.


Cogging Torque;Permanent Magnet;Maxwell Stress Tensor;Flux Density;Electric Machine


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