Torque ripple improvement for ferrite-assisted synchronous reluctance motor by using asymmetric flux-barrier arrangement

This paper introduces a low torque ripple ferrite assisted synchronous reluctance motor (FASRM), in which an asymmetrical rotor is designed. The key of the proposed FASRM is to minimize the reluctance torque ripple, which is the main source of the total torque ripple. A compensation method is proposed to optimize the opening angle of each flux barriers, which indicates this pole producing torque with consistency in phase and waveform. Moreover, two existing motors with the same dimension are used as benchmarks in order to evaluate the proposed FASRM. Additionally, both theoretical analysis and simulation results are provided to validate the good performances of the proposed FASRM. It is found that the proposed FASRM with the asymmetrical rotor can reduce the total torque ripple and avoid sacrificing the average torque.