Multi-objective optimal design of an axial flux permanent magnet wheel motor for electric scooters

This paper proposes a systematic process of a multi-objective optimal design of an axial-flux permanent-magnet motor for electric scooters. In the preliminary design, the zero-dimensional magnetic circuit model is used to determine the numbers of slots and poles and the initial size of the motor according to the driving requirements of scooter. In the optimal design process, the one-dimensional magnetic circuit model with an effective air-gap distribution function is used while searching a set of motor parameters that minimize torque ripple and maximize torque and torque density. The final design is verified and refined by the 3-dimensioanl finite element method. Experimental results on a motor prototype show that the proposed design process results in an axial-flux permanentmagnet motor with a high torque density for electric scooters.