A Maximum Power Point Tracking Scheme for PV Systems Using Model Predictive Control in Grid-Connected Packed U-Cell Inverters

This paper presents a new scheme for the maximum power point tracking (MPPT) in the grid-connected photovoltaic (PV) systems by the Packed U-Cell (PUC) inverter. A single-phase 7-level PUC inverter composed of six switches and DC link (secondary capacitor) is modeled to illustrate the proposed MPPT scheme. The PUC inverter employs the model predictive controller (MPC) with a cost function optimization (CFO) approach. The CFO approach optimally produces the switching states of the inverter so that the maximum power of the PV is extracted. To validate the functionality of the proposed MPPT scheme, a complete set of simulation results are provided using the MATLAB Simulink environment. According to the obtained results, it is verified that the proposed approach effectively controls the output voltage of the PV arrays, and subsequently, extract and inject the maximum power of the PV arrays into the grid by a high power quality.