Low Switching Frequency FCS-MPC Technique for Four-Level Inverters

The conventional finite control-set model predictive control (FCS-MPC) techniques are designed to operate at a high switching frequency, so that the reference current tracking error can considerably minimized. However, the high switching frequency operation causes a significant amount of switching losses, which is highly undesirable in high-power multilevel inverters (MLIs). In this paper, a new FCS-MPC technique is proposed to reduce the switching frequency of MLIs. In this technique, the average of the trajectories is considered in the prediction process of the control variables. This approach is applied to a four-level inverter, and the relevant discrete-time models are developed. The experimental studies are presented to verify the feasibility of the proposed FCS-MPC for a four-level inverter and are compared with the conventional FCS-MPC.