Optimization Technique for Improving Torque Performance of Concentrated Winding Interior PM Synchronous Motor with Wide Speed Range

Interior PM synchronous motors (IPMSMs) are used in many industrial and home appliance applications due to their advantages. However, the torque ripple and cogging torque of IPMSM are generally greater than those of surface permanent magnet synchronous motor. Furthermore, the IPMSM with concentrated winding is more disadvantageous than that with distributed winding in the respects. The problems are generated mainly by the discontinuous reluctance variation between the rotor and stator. Therefore, this paper proposes an optimization technique to reduce torque ripple and cogging torque without a great change of the motor parameters in the initial designed IPMSM. Moreover, the optimal models with respect to torque ripple at the base and maximum speed and cogging torque are compared with each other. In the end, response surface method combined with experimental design is applied as an optimization method, and the usefulness of the method is verified by the simulation results based on finite element analysis.