Optimization of a Spoke-Type Permanent Magnet Motor by Combination of Genetic Algorithm and Finite Element Method

The spoke-type permanent magnet motors with ferrite magnets provide relatively high torque density and high efficiency at a low cost compared to conventional structures and are widely applied in different drive systems. In this paper, a parametric finite element model of a spoke-type permanent magnet motor for washing machines is built up. Operating points at low speed and high speed are calculated respectively. An optimization process by using genetic method is then conducted, with the goal to find an optimal design that satisfies a list of constraints and has lowest cost. A fitness function is specially defined to deal with the object together with the constraints. The results show the feasibility of the proposed approach combining genetic method with finite element method.