Three-dimensional Analytical Modeling of Axial Flux Permanent Magnets Maglev Motor

Abstract

The three-dimensional(3D) analytical model of the magnetic field in an Axial Flux Permanent Magnets Maglev Motor(AFPMMM) is proposed and investigated the influence of the structural parameters on electromagnetic characteristics. Firstly, the topology and working principle of the AFPMMM is introduced, and the model is transferred into a mathematical model in 3D cartesian coordinate. Then, the volume integral method and equivalent current sheets model is applied to find the 3D magnetic field distribution function of Halbach rotor. A unified form expression can be obtained by two dimensional discrete fourier transform (2-D DFT) is applied on the 3D magnetic field distribution function. Thirdly, the conductive and nonconductive regions of AFPMMM will be formulated by the second order vector potential (SOVP) to built the 3D analytic model. The expression of the lift force, torque and power losses was derived. Besides, the relationship between electromagnetic characteristics and structural parameters of the AFPMMM were analyzed based on 3D analytic model and validated using the 3D finite element analysis(FEA). Finally, the experiments based on a small scale prototype are carried out to verify the analytical results.