Power Quality Enhancement using Dual-SOGI PLL with Pre-filter based Control Algorithm for DVR in Distorted Grid Conditions

Power quality is crucial for secure and reliable functioning of modern power systems, as the increasing use of sensitive equipment makes them more vulnerable to voltage harmonics, sags, and swells. To address these challenges, this work proposes a Dynamic Voltage Restorer (DVR) to maintain the required voltage stability, ensuring reliable operation of sensitive loads by mitigating voltage disturbances. An effective control is essential for the accurate operation of the DVR. This algorithm comprises a controller and a precise measurement system for grid phase angle, frequency, and magnitude of voltage, enabling accurate calculation of the DVR reference voltage. Traditional Phase-Locked Loop (PLL)-based control schemes can mitigate voltage sags and swells but are inadequate under grid voltage imbalances. To address this limitation, a Dual-Second Order Generalized Integrator with a Pre-Filter (DSOGI-WPF)-based algorithm is employed for reference voltage generation, improving DVR performance. The proposed approach is evaluated under diverse operating scenarios, including harmonic disturbances, linear and nonlinear loads, typical grid scenarios, and voltage imbalances. Furthermore, the efficacy of the proposed controller is evaluated against conventional methods. The control mechanism is implemented and simulated using MATLAB<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">®</sup> Simulink, showing its effectiveness in improving power quality and grid stability.