Int. J. Power Electronics, Vol. 20, No. 3, 2024 243 Copyright © 2024 Inderscience Enterprises Ltd. Presenting a control method using UPQC and PV array to reduce voltage drop and current harmonics during distribution system Alireza Rostamipour*, Mehdi Abdi and Amirhosein Ghayeni Department of Electrical Engineering, Islamic Azad University Mashhad Branch, Mashhad, Iran Email: alireza.rostamipour@srbiau.ac.ir Email: mehdi-abdi@outlook.com Email: a.m.ghayeni@gmail.com *Corresponding author Abstract: This research presents a new approach to address issues related to power quality that manifest in new ways, a control technique known as synchronisation reference frame (SRF). By employing a self-tuning filter in conjunction with the unit vector generation method (STF-UVGM), synchronisation between phases is obtained while UPQC remarkably demonstrates its performance, even in the case of imbalanced or distorted supply voltages. Consequently, there is no longer a necessity for phase-locked- loop, low-pass filters, or high-pass filters. Nevertheless, a self-tuning filter remains employed to separate harmonic and fundamental components. Furthermore, STF-UVGM has been implemented for generating synchronisation phases within the shunt filter. The performance evaluation of PV-UPQC has been extensively explored across three test cases involving different loads and supply voltages; in all scenarios, this proposed methodology exhibits exceptional efficiency as it effectively reduces total harmonic distortion (THD) and mitigates voltage distortions. The proposed PV-UPQC successfully reduces the current and voltage harmonics, as shown by the MATLAB simulation results. Keywords: SRF theory; PV-UPQC; active filters; self-tuning filter; power quality. Reference to this paper should be made as follows: Rostamipour, A., Abdi, M. and Ghayeni, A. (2024) ‘Presenting a control method using UPQC and PV array to reduce voltage drop and current harmonics during distribution system’, Int. J. Power Electronics, Vol. 20, No. 3, pp.243–265. Biographical notes: Alireza Rostamipour received his BE in Electrical and MSc in Power System & Drives degrees 2019 and 2022, respectively, from the Azad University, Mashhad, Iran. His principal research interests are PFC, SMPS and DC-DC converter. Mehdi Abdi received his BE in Electrical and MSc in Power System & Drives degrees 2019 and 2022, respectively, from the Azad University, Mashhad, Iran. His principal research interests are multi-phase multi-motor machine drives system.