Fuzzy logic based MPPT approach in a grid connected photovoltaic system

The maximum power point tracking (MPPT) is required for harnessing maximum power from the grid connected photovoltaic (PV) system. This paper describes a real time implementation of a grid connected photovoltaic system based on the fuzzy MPPT algorithm to control the power of the PV panel on the generation side as well as the current of the voltage source inverter (VSI) which is connected to the grid side. The performance of the control algorithm is verified by simulation and experiment. The implementation of the fuzzy algorithm is realized on a dSPACE 1104 single board by controlling a boost chopper and a VSI. The experimental results prove the effectiveness of the control techniques of the proposed fuzzy logic by fixing the MPPT in the I-V curve of the solar panel. The DC bus voltage controller based on Lyapounov theory and the hysteresis based current control of the inverter allow a quasi total transit of the maximum extracted power from the solar panel to the grid under unit power factor operation.