Command of a Connected PV System Under Grid Faults

This paper introduces a control method for grid-tied photovoltaic (PV) systems operating under voltage sag conditions. The control algorithm determines, in real-time, the maximum deliverable active and reactive power from the inverter, and uses these as input references, aligning with grid support standards. This approach permits to maintain grid connection during voltage faults, contributes reactive power, and enhances system robustness. The control structure relies on linear PI regulators and is tested via MATLAB/Simulink simulations using a 3 kWc PV generator.