Optimal design of spoke type motor to improve the torque constant and minimize torque ripple

Abstract

This paper proposes a new topology that combines the flux barrier configuration and the split permanent magnet structure of spoke type interior permanent magnet motor (SIPM) with concentrated winding to improve the average torque as well as the quality of torque. The flux barriers can reduce the leakage flux between the magnets inserted in the rotor. Whereas, splitting the magnet across the steel core can decrease the magnetic resistance of the rotor shape. Therefore, both techniques are combined to get their benefits together to improve the output characteristic. The structure is further optimized using Kriging method and Genetic Algorithm to obtain an efficient design within given constraints of the machine. It is demonstrated that torque constant of optimal model is improved. Moreover, cogging torque and torque ripples are minimized. Finite element analysis is performed to verify the proposed topology and the optimal design.