Fuzzy control of a grid connected three phase two stage photovoltaic system

This paper presents fuzzy logic control (FLC) of a grid connected two stage three phase photovoltaic system. The first stage consist of a DC-DC boost converter with maximum power point tracking (MPPT), and the second stage consists of a three phase grid connected PWM switched inverter. In the first stage, excess currents are transferred to the grid by using perturb and observation (P&O) MPPT algorithm. Fuzzy logic controller regulates the d-q axis currents for the inverter control. Proposed system was simulated using Matlab/Simulink under variable irradiation and temperature. The simulation results show that the proposed system achieved better performance in terms of dynamic responses, the axes currents follow the reference currents without overshoot and the settling time is very short.