Finite Control Set Model Predictive Control without Weighting Factors for Common Grounded Five-Level PV Inverter

Elimination of leakage currents is a critical issue for transformerless photovoltaic (PV) inverters. Multilevel common grounded (CG) PV inverters have become promising solutions for mitigating leakage currents. However, developing multilevel outputs and injecting high quality currents impose several challenges for classical controllers. Therefore, this paper presents a finite control set model predictive control, FCS-MPC, without weighting factors for the five level CG switched capacitor cells inverter. Moreover, tuning the weighting factors in the classical FCS-MPC requires performing several cases and comparing the different cases to select the best weighting factors. In the proposed FCS-MPC, the problem of weighting factor adjustment of the classical FCS-MPC methods is eliminated through dividing the cost function objectives. Hence, simplified and robust design is achieved using the proposed FCS-MPC method while avoiding long procedures for tuning the weighting factors. Simulation results of the proposed FCS-MPC method are provided to verify its performance.