| CPC H02P 5/74 (2013.01) | 29 Claims |

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1. A multiple electric machine system for use in a vehicle, the electric machine system comprising:
a first electric machine;
a second electric machine;
one or more power converters coupled to the first electric machine and second electric machine; and
a controller coupled to the one or more power converters and arranged to receive one or more inputs relating to the system, wherein the controller, in response to the one or more inputs, is configured to:
direct the one or more power converters in a first operating mode to cause both the first electric machine and the second electric machine to continuously output torque;
direct the one or more power converters in a second operating mode to cause the first electric machine to provide a pulsed torque output and the second electric machine to continuously output torque;
direct the one or more power converters in a third operating mode to cause both the first electric machine and the second electric machine to provided pulsed torque outputs, wherein at least sometimes during operation in the third operating mode, a timing of pulsing of the first electric machine is coordinated to be out of phase with pulsing of the second electric machine by a first phase delay to cause vibrations generated by pulsing of the first and second electric machines to be out of phase at a target location in the vehicle by a second phase delay to reduce noise, vibration and harshness (NVH) at the target location in the vehicle; and
wherein during each of the pulsed torque outputs, the controller causes the corresponding one of the first electric machine and second electric machine to alternate between an associated first output torque level and a zero output torque level.
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