Performance analysis of two BDCM drives for traction applications

In this article, a comparison is made between two brushless DC motors of the same rating, one is designed with a segmented permanent magnet (PM) poles whereas the other with one segment of permanent magnet poles. Both drives are aimed for traction applications. The drives performances are assessed using a coupled model which considers the motor and controller configuration. A special emphasis is made on torque and torque ripple. The analysis shows that the two topologies present more a less the same torque ripple over the whole operating speed range, and therefore the configuration with the segmented PM constitutes a more interesting drive solution from construction and performance point of views