Analytical Analysis of Cogging Torque in Motors of Permanent MagneticType

- Journal title : Transactions of the Korean Society of Mechanical Engineers A
- Volume 24, Issue 7, 2000, pp.1795-1800
- Publisher : The Korean Society of Mechanical Engineers
- DOI : 10.22634/KSME-A.2000.24.7.1795

Title & Authors

Analytical Analysis of Cogging Torque in Motors of Permanent MagneticType

Go, Hong-Seok; Kim, Gwang-Jun;

Go, Hong-Seok; Kim, Gwang-Jun;

Abstract

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.

Keywords

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

Language

Korean

Cited by

References

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