Design of a New Spoke-PMSM with Multiple Flux Barriers Considering Flux-Intensifying Effect for SWPS

In this work, the design of a new flux-intensifying spoke (FIS) permanent magnet (PM) synchronous motor (PMSM) consisting of multilayer rotor barriers, is presented. The conventional spoke-PMSM (CS-PMSM) exhibits high possibility of PM demagnetization and lower maximum speed in flux weakening region due to its operation with negative d-axis current. Besides, it requires high flux-weakening current, and thus exhibits lower efficiency for operation above rated speed. These drawbacks are overcome by the developed FIS-PMSM, which is designed while considering the flux-intensifying effect. Multiple flux barriers are introduced in q-axis flux path of the designed motor, which thereby results in positive saliency difference. Hence, the developed FIS-PMSM generates maximum torque on application of flux-intensifying current. To demonstrate advantages of FIS-PMSM, the comparison is made with the CS-PMSM, wherein an increment of 14.3% in operating speed and 21% increment in PM operating flux density are obtained. The other electromagnetic performances like torque curves, inductance profiles and efficiency plots are also acquired by performing finite element based simulation.