Torque ripple reduction in Reluctance Synchronous Machines using an asymmetric rotor structure

Reluctance Synchronous Motors combine high efficiency and high torque density in a limited speed range. This type of machine is increasingly becoming an alternative to Induction Machines, especially for pumps and industrial drives. However, the torque ripple of RSM, caused by the spatial variation of the machine flux and reluctance, needs to be considered during the design process. This paper presents an approach of torque ripple reduction using asymmetric flux barrier angles and a flipped rotor structure to compensate certain torque harmonics by superposition. With the described design process, the resulting torque ripple is strongly reduced without loosing average torque.