Pole-restraining control for npc three-level inverter

State-of-the-art control approaches often neglect the time-variant characteristics of power-electronic systems in favour of a time-averaged approach. In consequence, the resulting system is partly instable, thus, not optimally controlled. The pole-restraining control (PRC) removes the inherent instability, giving considerably improved dynamic behaviour. In this paper, the PRC approach is applied to the 3-level npc converter topology. The major extension is related to the instantaneous DC-link voltage balancing. These improvements are demonstrated for three-phase Active Front Ends (AFE) in npc three-level topology.using simulation results.