Double-Stage Three-Phase Grid-Integrated Solar PV System With Fast Zero Attracting Normalized Least Mean Fourth Based Adaptive Control

Abstract

This paper deals with a control technique of a three-phase grid connected solar photovoltaic (SPV) system, which is based on the fast zero attracting normalized least mean fourth algorithm. This control algorithm achieves the objectives of mitigation of power quality issues such as harmonics reduction and power factor correction, together with extraction of peak power generated by the PV array. The system uses a PV array, a voltage-source converter (VSC), and linear and nonlinear loads. Here, VSC is connected to a PV array to transfer the active power to the three-phase load and the grid. The dependence on tuning of proportional-integral controller is reduced because of the feedforward term of the PV power. Due to this, the system dynamic response is improved, which makes the system quite robust. The system goals are to mitigate power quality problems and to provide current conditioning while operating in coherence with a weak distribution grid, which has poor quality of power in terms of voltage distortions with imbalances. MATLAB/Simulink is used to develop the model of the proposed system. The validation of proposed control is done at varying linear and nonlinear loads and under different environmental conditions on a prototype developed in the laboratory.