Received February 2, 2022, accepted February 12, 2022, date of publication February 15, 2022, date of current version March 10, 2022. Digital Object Identifier 10.1109/ACCESS.2022.3151919 A New Technique Implemented in Synchronous Reference Frame for DVR Control Under Severe Sag and Swell Conditions SAAD F. AL-GAHTANI 1 , (Member, IEEE), ABDULWASA B. BARNAWI 1 , HAITHAM ZAKI AZAZI 2 , SHAIK M. IRSHAD 1 , JAVED K. BHUTTO 1 , MAJAHAR H. M. 1 , AND ELBARBARY Z. M. SALEM 1,3 1 Electrical Engineering Department, College of Engineering, King Khalid University, Abha 61421, Saudi Arabia 2 Electrical Engineering Department, Faculty of Engineering, Menoufia University, Shebeen El-Kom 32511, Egypt 3 Department of Electrical Engineering, Faculty of Engineering, Kafrelsheikh University, Kafr El-Shaikh 33516, Egypt Corresponding author: Haitham Zaki Azazi (haitham_azazi@yahoo.com) This work was supported by the Deanship of Scientific Research, King Khalid University, under Grant RGP.1/255/42. ABSTRACT Nowadays, power quality under the excessive implementation of power electronics devices is quite challenging issue. The compensation of non-sinusoidal; reactive and harmonic; components is the main role for power quality devices which highly depend on the robustness of the control system. Some common control systems are implemented using Synchronous Stationary Frame (DQ) theory. This paper proposes a new version of DQ control technique to control dynamic voltage restorer under severe transient voltage conditions. The power system network with the new DQ control technique is studied and analyzed under different scenarios to compensate for severe balanced and unbalanced voltage sags and swells. This new scheme is based on extraction of positive sequence components to implement the control algorithm. A mathematical model of the dynamic voltage restorer (DVR), hysteresis voltage control, converter controller model, new DQ scheme with complete system equations are carried out and verified using Simulink / MATLAB. The proposed system is validated experimentally using DSpace 1104 based laboratory system. The obtained results of the proposed compensation algorithm are compared with the results obtained from the traditional DQ method. Simulation and experimental results are correlated and show effectiveness of the proposed DQ control scheme. INDEX TERMS Balance and unbalanced load, dynamic voltage restorer (DVR), instantaneous space vector, synchronous stationary frame (DQ) theory, voltage sag, voltage swell. I. INTRODUCTION Medical equipment, factory automation, semiconductor- device manufacturers, and paper mills are among the sensitive loads that are sensitive to power-supply disturbances [1], [2]. The increase in demand of high power quality and voltage stability becomes a progressively critical concern with seri- ous threat and frequently occurring power-quality problem in today’s power grids. voltage sag, swell are now recog- nized as severe costly consequences such as sensitive loads tripping and production loss [3]. Voltage sag and swell are significant power quality issues that occur frequently during contingency, switching and unexpected load changes [4]. Severe storms and lightning on electricity lines trigger line The associate editor coordinating the review of this manuscript and approving it for publication was Ton Duc Do. to ground fault leading to voltage sag over a wide section of electrical network. Some other factors that results in this disturbances are short circuits at the starting of power trans- mission line, the parallel power distribution line linked to the point of common coupling (PCC), high inrush currents related with the starting of large machines, abrupt changes in load, the energizing of power transformers, and switching operations in the power system network [5]. Voltage sag is the temporary drop of the root mean square (R.M.S.) voltage at a location in the electrical system below a predetermined threshold. It is a short-duration variation of the RMSvalue of voltage from 10 to 90% of nominal voltage over a time longer than 0.5 cycles (10ms) of power frequency but less than or equal to 60 seconds [6]. The terms used to define the extent of voltage sag are frequently misunderstood [7], [8]. According to IEEE 1159-2019, a sag to 70% is permitted, VOLUME 10, 2022 This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License. For more information, see https://creativecommons.org/licenses/by-nc-nd/4.0/ 25565