Comparison of two different winding topologies for external-rotor five-phase PM-assisted synchronous reluctance motor in vehicle applications

摘要

This paper compares the performance of five-phase external rotor permanent magnet assisted synchronous reluctance motor (PMaSynRMs) for two different winding configurations. In vehicle applications, five-phase winding improves power density, fault tolerant capability and reduces torque pulsation compared to a conventional three-phase winding whereas the adoption of external rotor architecture increases the power density. However, the degree of freedom reduces in selecting winding configuration for multiphase motors which is very critical for performance of PMaSynRM. Therefore, for the design external rotor PMaSynRM, the winding topology like slot/pole combination and coil-distribution should be carefully selected to obtain higher power density with higher efficiency and lower cost. This paper compares the electromagnetic performance of two motors having two different winding topologies, one has fractional-slot concentrated winding (FSCW) with 15slot/12pole and the other one has fractional-slot distributed winding with 25slot/12pole. The analytical modeling and optimization procedure to obtain these motors have been discussed briefly followed by thorough finite element analysis to compare the performance of the motors. Finally, the experimental results have been presented to verify the induced voltage of one motor at no load condition.