FCS-MPC of Grid-Connected 9-Level Crossover Switches Cell Inverter

Abstract

In this paper, a finite-control-set model predictive controller (FCS-MPC) is designed for a grid-connected single-phase crossover switches cell (CSC) multilevel inverter (MLI). The CSC inverter is a modified 3-cell packed-U-cells (PUC) MLI by adding two crossover switches between the two DC-link and the flying capacitor. This modification allows the CSC to generate an output voltage with a peak value greater than the value of the DC source voltage (boost capability). The proposed FCS-MPC is designed, by selecting the appropriate weighting factor values for different design parameters, to inject current to the grid at unity power factor and low total harmonic distortion (THD) while regulating the capacitor voltage at the reference level. The proposed FCS-MPC is validated in simulation where the presented results show a high dynamic performance and capability of dealing with a multi-objective control problem at different operating conditions.