Fuzzy logic controller vs. PI controller for MPPT of three-phase grid-connected PV system considering different irradiation conditions

Abstract

In this paper, a comparison between fuzzy logic controller (FLC) and conventional proportional-integral controller (PIC) is presented for a connected PV array system to utility grid via a three-phase line-commutated inverter. The main objective of the controller is providing maximum power for utility grid in different solar radiation conditions. The simulink model of the studied schemes is built using MATLAB/PSB for generating firing pulses of the thyristors in the inverter by applying PIC and FLC methods separately. Three different radiation conditions are examined on both controller which are constant solar radiation, step solar radiation and a combination of step and ramp scheme. According to simulations, FLC dominates PIC for all radiation types and in many important aspects. Some of these aspects could be named as, extracting power from PV array, providing active power for grid, shape of output current of inverter, shape of grid current waveform and total harmonic distortion (THD) of these currents.