Analytical Model for a Transverse Flux Permanent Magnet Machine Using Improved Magnetic Equivalent Circuit Approach

This paper presents an analytical magneto-static model for a class of transverse flux permanent magnet machines based on Improved Magnetic Equivalent Circuit (IMEC) of the machines. The model is useful for the design and performance evaluation of the transverse flux machine. The model consists of a series-parallel combination of flux tubes for different parts of the machine including air gaps, the permanent magnet in the rotor, and the stator and rotor ferromagnetic materials. The equivalent circuits of the model are obtained based on permeance calculation of the magnetic flux paths within the machine. A prototype of an 8-pole transverse flux permanent magnet machine has been developed and the analytical modeling approach has been used for modeling of this machine. The validity of the proposed model is verified by comparing the finite element (FE) results with the results obtained from the model and also comparing the measured inductance of the prototype machine with those of predicted based on the analytical model. Comparing the model and measured inductances shows that the analytical model is able to accurately describe the magneto-static behavior of the machine with an average error less than 7%.