Enhancing Grid Performance of Single-Stage PV Systems Using Modified SRF Theory and SAPF with Quasi-Z-Source Inverter

This paper presents an innovative solution for the enhancement of the single-stage photovoltaic systems grid-tied topology. The proposed approach involves the integration of an Active Power Filter (APF) with a Quasi-Z-Source Inverter (qZSI) that are controlled by a modified Synchronous Reference Frame (SRF) approach. Indeed, the conventional grid-tied PV systems often face challenges such as grid instability, harmonic distortion, and power quality issues. These issues can lead to inefficient energy transfer and potential damage to grid equipment. In response to these challenges, the proposed system integrates an APF with a qZSI that allows offering advanced grid-support features including harmonics mitigation, reactive power compensation, and voltage regulation. The proposed topology based on qZSI-APF can actively manage the power flow and ensure grid stability of operation mode of the single-stage photovoltaic systems grid-tied even under varying operating conditions. Furthermore, the applied control strategy, based on a modified SRF approach, enables precise current control and seamless interaction with the grid. Hence, the combination of the proposed topology with the applied control technique allows ensuring efficient utilization of renewable energy resources while maintaining the grid reliability and stability. For the validation of the proposed topology, simulations based on Matlab/Simulink environment have been carried out to prove the effectiveness of the proposed topology. The obtained results demonstrate improved grid integration performance, reduced harmonic distortion, enhanced power quality, and better voltage regulation. It can be said that the proposed topology offers a promising solution for addressing the challenges associated with grid integration of PV systems, paving the way for overcoming the main faced problems related to the increased renewable energy deployment and hence ensuring sustainable and clean energy sources.