Analytical Calculation of Slotless Permanent Magnet Motor Based on Soft Ferrite

Abstract:

High-speed slotless permanent magnet brushless motor based on soft ferrite adopts a large effective air gap structure. For the large effective air-gap, the air-gap flux distribution becomes uneven and the end leakage flux significantly increases. Thus, the traditional analytical method of the phase EMF is inapplicable. This paper deduces the analytical expression of the phase EMF based on the analytical calculation of the air-gap field and analyzes the distribution of the end leakage flux by 3D finite elements methods. Then the end leakage flux is considered by a correction factor of the core length. Finally the analytical calculation method is proved to be feasible by the comparison between the finite elements results and the prototype test results.

• Periodical: Applied Mechanics and Materials (Volumes 397-400)
• Pages: 501-504
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.397-400.501
• Online since: September 2013
• Authors: Xin Yi Zhang, Xing Hua Wang, Ming Hui Li, Xue Qin Zhang
• Keywords: Electromotive Force, End Leakage Flux, High-Speed Motor, Soft Ferrite

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