Determination of air-gap flux density due to magnets using the new analytical model

In this research work a new and simple calculation model for the analysis of the salient pole PM machines taking into account the stator slotting effect is presented. The approach to analyze the air-gap flux density based on the new model is to determine the air-gap magnetomotive force (MMF) and the flux path permeance function. The air-gap MMF for different rotor topologies is described with the well known Fourier series function, however, the flux path permeance function taking into account the stator slotting is determined using a simple magnetic reluctance network. Using the new model the air-gap flux density distribution for a PM machine is calculated. FE methods are used to prove the accuracy of the new model. Also, the effect of magnet volume (magnet length and width) in the air-gap flux density is investigated.