MPC Design and Comparative Analysis of Single-Phase 7-Level PUC and 9-Level CSC Inverters for Grid Integration of PV Panels

In this study, a novel comparison between single phase 7-Level Packed U - Cell (PUC) and single phase 9-Level Cross Switches Cell (CSC) inverter with Model Predictive Controller (MPC) for solar grid-tied applications is presented. The efficacy of photovoltaic (PV) solar panels as a sustainable energy source is explored through the proposed inverter topology. Our innovation introduces a unique approach by integrating PV solar panels in PUC and CSC inverters in their two DC links rather than just one which increases power density of the system. The main benefit of both proposed models, other than the system’s power density, is their overall simplified design in comparison to other current topologies, thus both topologies offer enhanced power quality with reduced system complexity compared to traditional configurations. Moreover, the primary benefit of the used control topology for both designed models lies in its streamlined architecture, which eliminates the need for additional controllers such as PI controllers for grid reference current extraction. Furthermore, the implementation of Maximum Power Point Tracking (MPPT) technology directly optimizes power output from the PV panels, negating the necessity for a DC-DC booster converter during integration. To validate the proposed concept's performance for both inverters, extensive simulations were conducted using MATLAB/Simulink, assessing both inverters under steady-state conditions as well as various disturbances to evaluate its robustness and dynamic response. Both inverters exhibit robustness against variations in grid voltage, phase shift, and irradiation. By comparing both inverters, results demonstrate that the CSC inverter exhibits superior performance due to its booster feature which relies on generating voltage level greater than the DC input source. This primary advantage makes CSC a booster inverter.