Torque ripple reduction in five-phase induction machines using mixed winding configurations

In this paper, the authors take a particular look at the effects of combination of different stator winding configurations in a 40 stator slots, 2-pole, and five-phase induction machine. They show, through computer simulation, that the combination of double and triple layer with 19/20 coil pitch reduced the torque ripple from 19.1%, for the conventional single layer full pitch, and from 10.6%, for the conventional double layer with 19/20 coil pitch having the same rating, down to 8.7% while maintaining the torque average. The same has to be said for the double combination which is the combination of double and triple layer combined with slot shift and coil side shift in one slot having 9/10 coil pitch. This double combination reduces tremendously the torque ripple from 28.8%, for a conventional double layer 9/10 coil pitch, down to 10.2% and still maintained the torque average. Some other winding combinations reduce both average and torque ripple.