Analytical Model for Axial Flux PM Machines with Halbach Arrays: Taking into Account of Rotor Iron.

In this paper, a general analytical model is proposed to consider the thickness of backplate of axial flux permanent magnet (AFPM) machine with Halbach arrays. Firstly, the machine is represented in a 3-region model, viz, rotor iron, PM and airgap region, then, the slotless flux density is developed by Maxwell's equations. Second, the Schwarz-Christoffel (SC) mapping technique is introduced to consider the slot effect. Moreover, a simple magnetic equivalent circuit is introduced to calculated the magnetic permeability of rotor iron. The results show that the analytical predictions agree well with the finite element (FE) results, also, the model is verified via the performance of experimental results. The main contribution of this model is that the rotor iron part is taken into consideration, which is more accuracy.