Minimization of Torque Fluctuation in Disc Type In-Wheel Motor Based on Response Surface Method and FEA

Aiming at development of in-wheel motor direct drive for mini electric vehicles, the paper presents a disc type permanent magnet synchronous motor (PMSM) with combination of 27-slot/24-pole. In order to suppress the torque fluctuation of the motor, the coupling method of response surface method and finite element analysis (FEA) for optimum parameter design of the motor is proposed. The mathematical model of response surface is established. The torque fluctuation ratio is decreased to a low level by optimization. The paper demonstrates that the disc type PMSMs have strong merits for in-wheel direct drive application of electric vehicles, and provides an effective solution for optimization of complicated three-dimensional electromagnetic structure based on finite element method (FEM).