Current Control Technique for Three-Phase Grid-Connected PV System in DQ Frame

Designing an AC side controller for a three-phase photovoltaic (PV) inverter that is connected to the grid with a third-order LCL filter is a difficult and complicated task because it involves many variables. To address this issue, a new control method is suggested, which integrates the existing sliding mode control (SMC) technique with a capacitor current feed-forward control to reduce grid current distortion. Moreover, an adjusted exponential model is added to address the recurring fluctuations commonly observed in conventional SMC techniques. This integrated SMC strategy is explained in detail, including its theoretical framework and design methodology. A simulation model of a grid inverter that can handle 50 kW of power and has three phases is created using a software tool called MATLAB/Simulink to evaluate the proposed strategy. We compare our new method with the usual methods to see how well it works and how much better it is. The proposed strategy has been proven effective through simulation and experiments, demonstrating enhancements in both the steady-state and transient grid current regulation.