Optimal slot/pole and flux-barrier layer number combinations for synchronous reluctance machines

AC synchronous reluctance machine (SynRM) or permanent magnet assisted synchronous reluctance machine presently receives a great deal of interest, since there is less or even no rare earth permanent magnet in the rotor. Most of SynRM machines employ a stator that is originally designed for a standard squirrel cage induction motor for a similar output rating and application, or the SynRM machine with 24-slot, 4-pole are often directly chosen for investigation in most of the available literature. Therefore, it is necessary to investigate the influence of stator and rotor pole number combinations together with the flux-barrier layers number on the performance of SynRM machine with emphasis on output torque capability and torque ripple. In order to investigate the impact of slot/pole number combinations on performance of SynRM machine, the same ratio of rotor insulation width to the rotor iron width has been used for all the slot and pole number combinations machines. In addition, the effect of flux-barrier layer number of this machine on average torque and torque ripple has also been investigated.