Axial flux permanent magnet machine desing and optimization using multi-layer 2-D simulation

This paper presents the design of an axial flux permanent magnet machine for in-wheel application. The machine design and optimization are developed using two-dimensional (2-D) multi-layer finite element analysis approach. The three-dimensional model of the machine has been approximated with a set of simulations in which the two-dimensional geometrical parameters were varied appropriately in order to reproduce the actual three-dimensional magnetic behavior. During design optimization, special attention was paid to the reduction of flux linkage harmonic content and to the reduction of cogging torque through the change of the permanent magnet profile and dimensions. Finally, a prototype machine was built to validate the effectiveness of the proposed method.