Improved Method for Calculating Magnetic Field of Surface-Mounted Permanent Magnet Machines Accounting for Slots and Eccentric Magnet Pole

- Journal title : Journal of Electrical Engineering and Technology
- Volume 10, Issue 3, 2015, pp.1025-1034
- Publisher : The Korean Institute of Electrical Engineers
- DOI : 10.5370/JEET.2015.10.3.1025

Title & Authors

Improved Method for Calculating Magnetic Field of Surface-Mounted Permanent Magnet Machines Accounting for Slots and Eccentric Magnet Pole

Zhou, Yu; Li, Huaishu; Wang, Wei; Cao, Qing; Zhou, Shi;

Zhou, Yu; Li, Huaishu; Wang, Wei; Cao, Qing; Zhou, Shi;

Abstract

This paper presented an improved analytical method for calculating the open-circuit magnetic field in the surface-mounted permanent magnet machines accounting for slots and eccentric magnet pole. Magnetic field produced by radial and parallel permanent magnet is equivalent to that produced by surface current according to equivalent surface-current method of permanent magnet. The model is divided into two types of subdomains. The field solution of each subdomain is obtained by applying the interface and boundary conditions. The magnet field produced by equivalent surface current is superposed according to superposition principle of vector potential. The investigation shows harmonic contents of radial flux density can be reduced a lot by changing eccentric distance of eccentric magnet poles compared with conventional surface-mounted permanent-magnet machines with concentric magnet poles. The FE(finite element) results confirm the validity of the analytical results with the proposed model.

Keywords

Permanent magnet machines;Magnetic field;Eccentric magnet pole;Surface current;

Language

English

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