Finite-Element Analysis of an Axial Flux Hysteresis Motor Based on a Complex Permeability Concept Considering the Saturation of the Hysteresis Loop

Axial structures of the hysteresis motors, similar to the other axial types of electrical machines, have some outstanding characteristics with regard to radial structures, such as higher torque-to-weight ratio, excellent efficiency, adjustable airgap, and balanced rotor-stator attractive forces. Since the accurate measurement of the hysteresis machine characteristics by prototyping and testing is expensive and time consuming, in this paper, the finite-element analysis is adopted for the prediction and analysis of an axial flux hysteresis motor. The analysis is conducted based on the elliptical approximation of the hysteresis loop. Since the elliptical approximation is not able to model the saturation of the hysteresis loop, an iteration-based method is proposed to overcome this problem and increase the analysis accuracy. Finally, in order to investigate the proposed model accuracy, the device is prototyped, whose experimental results agree well with those extracted from the analytical model.