In this paper, the implementation of a multilevel inverter-based DVR for power quality improvement in the electrical distribution systems is presented. The proposed system is designed to mitigate voltage disturbances, including voltage sags, voltage swells, and short-duration interruptions, which affects the performance and reliability of sensitive electrical loads. DVR have been widely known as effective custom power devices for voltage compensation in distribution networks [1], [4], [9]. To overcome the limitations, a multilevel inverter topology is incorporated to achieve improved output voltage quality, and to reduce THD, lower switching losses, and enhanced conversion efficiency [10]. The proposed DVR employs a PWM-based control strategy to detect voltage disturbances and inject to the required compensating voltage through the series injection transformer, thereby maintaining the load voltage within acceptable operating limits. The complete system is modelled and analysed in the MATLAB/SIMULINK environment under different voltage sag and voltage swell conditions. The proposed Multilevel inverter-based DVR provides a reliable and scalable solution for enhancing power quality in modern distribution systems and offers a suitable platform for future implementation using advanced control techniques [2], [3], [5]-[8].

Keywords- Dynamic Voltage Restorer, Multilevel Inverter,  PI Controller, Power Quality Improvement, THD, PWM Generator