3D Finite Difference Model of the Open Circuit Field of Permanent Magnet Spoke Type Axial Flux Machines

This paper deals with Spoke Type Permanent Magnet Axial Flux Machines which have a great interest in transportation applications. Indeed, as the other permanent magnet axial flux machines they can have very high specific torque. The spoke type architecture has ability for flux weakening. 3D finite difference model of the open circuit field is developed. In order to reduce the number of unknowns, the magnetic scalar potential formulation is used. According to the geometrical symmetries of the motor, the study domain can be reduced strongly. These choices contribute to get a fast computation time. The obtained results from this approach are compared to the results obtained by 3D finite element analysis.