A new approach to analyse magnetic field distribution in PM motors

The finite element method is often used in determination of magnetic field distribution in permanent magnet motors. The main limitation of this method is that it is time consuming and requires special software packages. The proposed analytical method is capable of predicting field distribution in the air gap and magnet region of both external and internal rotor types of permanent magnet motors, by solving the general Laplacian equations describing field distribution in each region. Simplicity is the main advantage of the proposed method and it is shown that close agreement is achieved between results obtained using the proposed analytical approach and conventional numerical methods.