Electerical Engineering, Isfahan University of Technology
Electerical and Computer Engineering, Isfahan University of Technology
Both the cogging and electromagnetic torques depends on the shape of the flux density distribution in the airgap region. A two-dimensional (2-D) analytical method for predicting the open- circuit airgap field distribution in brushless permanent magnet motors, considering the direction of magnetization, i.e., radial or parallel, and the effect of real shape of stator slot-openings is presented in this paper. It involves the solution of the governing field equations in polar coordinates in airgap and magnet regions. This method uses a new 2-D relative permeance function. For the comparison purposes, a 2-D finite element (FE) analysis is used for the analysis of a fully-pitched, double-layer windings brushless permanent-magnet (PM) drive. The results obtained by this method are very close to those obtained by FE analysis especially at the corner tips of the tooth.