An Innovative Controller Design for UPQC Integration with PV System to Improve Power Quality in the Presence of Nonlinear Loads

This article introduces an innovative design for the series and parallel converters within a modern Unified Power Quality Conditioner (UPQC) that integrates a photovoltaic (PV) system on the DC link. These converters are installed alongside the network and sensitive loads, with the DC link being powered by a distributed photovoltaic generation system. Additionally, the control system implemented in these series and parallel converters efficiently manages power quality disturbances, including voltage sags, deep and prolonged voltage swells, and harmonics when nonlinear loads are present within a distribution microgrid. To enhance performance, the control circuit incorporates phase-locked loops and harmonic filters into the switching system, aiming to improve voltage symmetry and address harmonic loads, aspects that were previously neglected in earlier research. Ultimately, through simulation results, this article illustrates the equipment’s capabilities and success in maintaining voltage levels during voltage sags, deep and prolonged voltage swells, and in the presence of nonlinear and harmonically-rich loads, all under the control of the proposed method.