Optimal Shape Design of Interior Permanent-Magnet Synchronous Motor

Optimal shape design of interior permanent-magnet (IPM) synchronous motor has large effect in reducing the torque pulsation of the motor. However, the shape design variations should be feasible and manufacturable. In this research, optimal shape is obtained by drilling small circular holes in rotor. Optimal position and radius of these holes are found to effectively suppress the torque pulsation of IPM motor-drive on different steady-state and load conditions. A coupled magnetic field, electrical circuit, and mechanical system program is developed for the optimization purpose. Time stepping finite element method is used for the magnetic field analysis. The optimal design has been evaluated at different operating conditions, which shows good improvement in all load conditions. The optimal design also shows improvement in the field weakening region for high speed operation