Rotor Asymmetry Impact on Synchronous Reluctance Machines Performance

Synchronous Reluctance Machine has attracted increasing attention for high performance applications. However, they can be vulnerable to high torque ripple if they are not properly designed. In this paper, it is analyzed how the rotor geometry has a high influence on its performance. A rotor structure with two flux barriers per pole is optimized using a Multi-Objective Genetic Algorithm and Finite Element Method. The different conditions imposed in the optimization lead to two final models, one symmetrical and one asymmetrical of the rotor flux barriers. When comparing the performance indexes of the final models, a considerable improvement is observed in the asymmetric model, which achieves a reduction of more than 40% in the ripple torque without sacrificing the average torque, the power factor also improves and the harmonic distortion in the flux density decreases.