Power Quality Enhancement of Grid-Connected Photovoltaic System Using Fuzzy-PI Control

In this paper a three-phase grid connected Photovoltaic (PV) system using a Fuzzy-PI technique is proposed. The aim of the work is to improve the dynamic performances, guarantee a high quality of the THD despite irradiance variation and extract the maximum power while ensuring unity power factor. First, the whole system is presented in d-q-synchronous reference frame. After that, the Fuzzy-PI controller designed. PI controller parameters are adjusted online by Fuzzy rules. The proposed control is implemented in Matlab/Simulink environment and compared with the conventional proportional integral controller. The results show that the proposed control laws provide better performance in terms of references tracking and unity power factor. Furthermore, the harmonic analysis and total harmonic distortion revealed that the power quality injected into the electrical network is enhanced using the Fuzzy-PI control.