Magnetostatic Field Analysis of Disk-Type Permanent-Magnet Motors

The aim of this paper is to analyze the magnetostatic field of disk-type permanent-magnet motors by utilizing the 1-D equivalent magnetic circuit approach and the finite-element method. A 1-D equivalent magnetic circuit model, which is analogous to an electric circuit model, of the disk-type permanent-magnet motor is proposed. The accuracy of the analytical model is verified by a commercial 3-D finite-element analysis (FEA) package. The result shows that the air-gap flux density is in good agreement with an acceptable error of about 1.66%. The presented magnetic circuit approach is not only an accurate technique in predicting the magnetostatic field of disk-type permanent-magnet motors, but also effectively reduces the computing time. It is especially suitable for the preliminary design and optimization of permanent-magnet motors with axial-flux topologies.