Influence of Slot/Pole Combinations on the Performance of Dual-Rotor Axial-Flux Surface-Mounted Permanent Magnet Electric Motor for Automotive Applications

In this paper, the authors present a comparison between different structures of axial flow electrical machines - dual rotor - surface mounted permanent magnets - yokeless stator and concentric winding. The comparison is made with iso-geometric dimensions (size and weight) and iso-electrical parameters (current and supply voltage) between different slots / poles combinations. The main objective is to classify these structures according to the torque density. A second classification based on electromagnetic performance (losses, power factor, demagnetization risk) is also performed, considering the specification of medium-size electric car. The study is performed using 3D-FEA calculations for better accuracy of the results.