A current control strategy for a grid connected PV system using fuzzy logic controller

Abstract

This paper presents a scheme for controlling the flow of current from a grid connected photovoltaic (PV) generator while supplying power to the utility grid. The proposed system utilizes a fuzzy logic controller (FLC) to control the injected current through the PV inverter switches. The controller employs error and change of error in current as inputs. In the design, asymmetrical triangular membership function (MF) with five linguistic variables (LV) is used for the inputs while asymmetrical triangular MF with nine LV is adopted for the output. The proposed inverter control system along with 435V PV module is then developed in Matlab/Simulink to illustrate the effectiveness of the controller. The results show that the controller can effectively supplies rated root mean square voltage of 240V. Furthermore, the total harmonic distortion of the current waveform is found to be 1.45%, which meets with international standard.