A comparative study of synchronous reluctance machine performance with different pole numbers for automotive applications

This paper presents a comparative study on the effects of the number of poles on the synchronous reluctance machine´s magnetic and mechanical performances for automotive applications. In automotive applications the design limitations i.e., proper size, maximum speed, torque envelope, and converter rating make the design sensitive to magnetic and geometric parameters such as the number of poles. Low torque ripple requirement for traction motors leads to the number of poles higher than two. From a rotor geometry point of view the number of poles higher than six would not be feasible in today´s compact traction motors. Two different motor alternatives using 4 and 6 poles have been designed using a sizing methodology. In this work, machines equipped with transversally laminated anisotropic rotors. Magnetic and mechanical performances of the machines are analyzed and compared with regards to the design requirements. Finally, the proper design alternative will be addressed for automotive applications.