Abstract: The present disclosure relates to an electric drive apparatus 201, 202 comprising an inverter system 220, an electric motor 230 and a controller 290. The electric motor 230 includes a rotor 234 and a plurality of phase windings 221, 222, 223, 224. The inverter system 220 is configured to provide a respective current waveform 321, 322, 323, 324 to each of the phase windings 221, 222, 223, 224 of the electric motor 230. Each current waveform 321, 322, 323, 324 is defined by a group of electrical characteristics including: a frequency composition, a phase shift relative to a reference waveform 349, and an amplitude. For one or more of the current waveforms 321, 322, 323, 324, the controller 290 is configured to control one or more of the group of electrical characteristics to cause a periodically varying torque to be applied to the rotor 234.

Abstract: The present disclosure relates to an electric drive apparatus 201, 202 comprising an inverter system 220, an electric motor 230 and a controller 290. The electric motor 230 includes a rotor 234 and a plurality of phase windings 221, 222, 223, 224. The inverter system 220 is configured to provide a respective current waveform 321, 322, 323, 324 to each of the phase windings 221, 222, 223, 224 of the electric motor 230. Each current waveform 321, 322, 323, 324 is defined by a group of electrical characteristics including: a frequency composition, a phase shift relative to a reference waveform 349, and an amplitude. For one or more of the current waveforms 321, 322, 323, 324, the controller 290 is configured to control one or more of the group of electrical characteristics to cause a periodically varying torque to be applied to the rotor 234.