Abstract: A multilevel converter structure made up of cells in cascade, each intermediate cell containing two switches, with one pole of each of the two switches forming part of a pair of upstream poles and the other pole of each of the switches forming part of a pair of downstream poles, the pair of downstream poles of an upstream cell being connected to the pair of upstream poles of a downstream cell, the converter structure also having a respective capacitor for each cell, each capacitor being connected between the two poles constituting the pair of downstream poles of its cell.

Abstract: An electric machine control system includes a torque smoothing device including a torque monitoring device connected to the electric machine and supplying torque signals. A smoothing processor receives the torque signals and receives at least one torque reference signal and produces torque smoothing signals. A smoothing generator receives the smoothing signals and supplies smoothing electric power to the machine to make its torque conform to the torque reference.