Design of a surface PM vernier motor for a practical variable speed application

In order to verify the possibility for practical application of vernier motor, a motor with surface PM configuration has been designed for use in a commercial washing machine. First, a previously existing PM motor with an outer rotor, is investigated by using its equivalent circuit parameters. Next, the circuit parameters of vernier motor are formulated in terms of practical design variables. A new vernier motor with high power density is designed by comparing its characteristics with the parameters of the previous motor. The performance of the motor is then investigated with FEM. Finally the designed vernier machine is fabricated and numerous performance features are measured. Finally, the feasibility and problems related to such a machine are discussed.