An improved predictive current control method for grid-connected inverters

Abstract

This paper introduces an improved predictive current control strategy for reducing the output current harmonic content of single-phase grid-connected inverters, based on nonlinear filter inductor model. The proposed control strategy, takes both saturation and hysteresis loop effects into account to produce an appropriate voltage to mitigate unwanted harmonic contents of injected current. Also, it only uses the grid voltage and a simple PI controller to produce the switching times and maintain the DC-bus voltage on its nominal value. Performance of the grid connected inverter and the proposed control method are evaluated based on digital time domain simulation studies in the MATLAB/SIMULINK environment. The studies demonstrate the capability of the proposed control strategy to fulfill the IEEE 929 – 2000 standard for the current total harmonic distortion.