Enhanced IAF-PNLMS Based Control Algorithm for Power Quality Improvement in Weak Grid Interfaced Solar PV System

This paper deals with the power quality improvement of a double stage solar PV (Photovoltaic) energy conversion system through an EIAF-PNLMS (Enhanced Individual Activation Factor Proportionate Normalized Least Mean Square) based control algorithm. This EIAF-PNLMS based algorithm uses the benefit of this scheme, which is used to improve the filter coefficient. Therefore, the dynamic and steady state oscillations from the load fundamental current component is eliminated. The control algorithm gives the fast convergence, good frequency response, harmonics mitigation, and noise cancellation. The UDDBC (Unidirectional DC-DC Boost Converter) is the bridge between the solar PV array and DC-link of the VSC (Voltage Source Converter). This UDDBC is to extract the peak power from the solar PV array and this UDDBC switching pattern is governed by adaptive P&O (Perturb and Observed) based MPPT (Maximum Power Point Tracking). This adaptive P&O based MPPT algorithm has good tracking capability and it has high immunity from the rapidly solar irradiance perturbation. Here, FOIQGI (Fourth Order Improved Quadrature Generalized Integrator) based voltage filter, is used to mitigate the grid voltage distortions. Test results of the proposed solar interfaced grid system demonstrates satisfactory operation and effectiveness of control algorithm.