Comparative Study and Evaluation of Doubly Salient PM Motors with Different Stator/Rotor-Pole Number Combinations and Stator Iron Core Segments

This paper presents a comparative study and evaluation of doubly salient PM (DSPM) motors with different stator/rotor-pole number combinations and stator iron core segments. Firstly, their machine topologies and working principles are described. Thereafter, electromagnetic performance is analyzed under no-load and load conditions, mainly including back-EMFs (back-electromotive forces), cogging torque, inductances, and so on. The results reveal that by changing conventional E-core segment of stator and 12/8-pole combination, the 12/11- and 12/13-pole T-core DSPM motors benefits from very low torque ripple, although the torque is slightly reduced.