Analytical Study on Axial Flux Permanent Magnet Machines Considering Leakage Flux Based on Subdomain Method

In this paper, an improved analytical method for axial flux permanent magnet machines considering leakage flux is presented. Based on the assumption that the magnetic vector potential in the r direction is uniform, the analytical model in the polar coordinate system is simplified from a three-dimensional model to a two-dimensional model dependent on z and . and the magnetic vectorθ potential is then derived for analysis region. The electromagnetic characteristics of the analysis model are calculated using the derived magnetic vector potential. A magnetic equivalent circuit for calculating the leakage flux in the r-z plane is defined and the leakage coefficient is derived. The electromagnetic characteristics derived from the proposed analysis method are compared with the results from 3D finite element analysis to verify its validity.