Performance Analysis And Optimization Of Synchronous Reluctance Machines

Synchronous reluctance machine(SynRM)has attracted much attention recently for the low cost AC drive applications,thanks to the advantages of low cost,manufacturing simplicity,robust structure and high torque density.However,the parameters to be optimized for the SynRM are quite a lot and are dependent on each other.This makes the optimal design rather difficult.Besides,the power factor of the SynRM is inherently low,and the torque ripple is often large.Therefore,investigation of the optimal design method,and analysis of the influences of the structure parameters on the machine performance,are of great significance.In this thesis,the conventional design methods of the SynRM are reviewed.The implementation diagram of each method is pointed out,and both the advantages and disadvantages of these methods are analyzed.Then,a fast prediction method is proposed to design the initial parameters of the SynRM.Besides,effect of the design parameters on the machine performances is investigated.Optimization rules of the number of pole-pairs,split ratio,winding configuration,stator core and rotor core are discussed.Finally,the stators and rotors of the SynRM and the conventional switched reluctance machine(SRM)are combined alternatively,resulting in four machine structures.Performances of the four prototypes are evaluated to conclude the advantages and disadvantages.Moreover,performance of the permanent magnet assisted synchronous reluctance machine(PMA-SynRM)is compared with that of the SynRM.