Optimization-based design of fractional PI controller for a three phase grid connected PV system

This paper presents a robust control of a grid connected photovoltaic (PV) system. Fractional-order proportional-integral (FO-PI) and integer-order proportional-integral (IO-PI) current controllers are proposed. An optimization algorithm is implemented in order to determine the two current controllers parameters. A comparative analysis of the FO-PI and IO-PI improves the effectivness of current control using fractional order controller. In the proposed system, the control strategy enhances stability and system robustness, maximum power point tracking (MPPT) and total harmonic minimization.