Direct and quadrature axis voltage and current control of a three phase grid connected PV system with Adaptive Fuzzy Logic MPPT Controller

For improving dynamic response of grid connected photovoltaic systems voltage source inverter are operating in inner voltage and current control loop. This paper presents, a control technique for three phase grid connected photovoltaic system. Two stage power conditioning units has been used for system interfacing. First stage comprises of DC/DC converter and DC/AC conversion is done by voltage source inverter in second stage. Adaptive Fuzzy Logic Controller (AFLC) maximum power point tracking (MPPT) is proposed to achieve maximum power point operation. Using direct and quadrature axis voltage and current control voltage source inverter provides ac voltage by DC/DC boost converter output and total harmonic distortion (THD) is controlled as per IEEE Standard 929-2000. Finally, MATLAB/Simulation is carried out to confirm system operation and results.