Power and Efficiency Measurements and Design Improvement of a 50kW witched Reluctance Motor for Hybrid Electric Vehicles

A switched reluctance motor is one of possible candidates of rare-earth-free-motors. A prototype machine has been designed, having competitive dimensions, torque, power, and efficiency with respect to the IPMSM employed in the HEVs (Toyota Prius 2003). In this paper, test results are presented including a full load test. It is found that competitive power and efficiency of 50kW and 95%, respectively, are achieved, although 85% of the target torque is possible. Despite of the maximum torque, the most speed-torque region is found to be covered by the test SRM. The cause of discrepancy in the measured and calculated torque values is examined. Considering the discrepancy a new machine is designed for the second stage development.