A new robust control for grid connected photovoltaic systems based on active disturbance rejection control

The aim of this study is to improve the stability performance of grid connected photovoltaic (PV) systems with LCL filters. PID controllers are commonly used in these systems but they are not well adapted to parameters uncertainties, sudden change in the climate conditions and disturbances. This paper proposes an alternative robust control strategy to ensure the maximum extraction of the available power and the efficient transfer of the solar energy to the grid by using the active disturbance rejection control. This control technique provides better performances by increasing the system efficiency and ensuring stability under parameter variations and disturbances. Moreover, the LCL filter resonance is actively damped with a minimum complexity in the controller design, and without any adaptive algorithm. The effectiveness of the proposed control is demonstrated through simulation results, in which its performance is shown to be superior to that of the conventional PID controller.