Performance Analysis of High Power Brushless DC Motor Drive

Brushless motors are replacing most of the conventional application that were driven by induction motors in recent times. This is majorly due to the advancement and the proliferation of control techniques for the operation of such machines. The critical choice in electric vehicle applications is on the capability of motoring and generative characteristics. These types of machines are viable candidate as with its extended constant power range operation replacing the conventional multi-gear transmission. However, the major challenges in such type of machines is twofold, one with the cogging force generated in the operation mainly due to the magnetic orientation of the machine and the second one due to the switching ripple significantly increase the ripple content in the machine. In this paper, the performance of the 5 kW BLDC machine used for electric vehicle operation is reported in terms of torque and current characteristics.