A Novel Three-Phase Low Voltage (LV) Dynamic Voltage Restorer (DVR) Employing Semi-Z-Source Inverter

Abstract

This paper presents the design and control of a Low Voltage (LV) Dynamic Voltage Restorer (DVR) for a three-phase power system. The DVR is designed to protect a three-phase load of 3 kVA from the voltage sags and swells ranging up to 0.5 p.u of the supply voltage. The proposed DVR utilizes semi-Z-source (SZS) inverter as the power converter in each phase of the DVR. The SZS inverter offers many advantages such as reduction in cost, size, weight, elimination of filter etc. compared to the conventional Full Bridge (FB) inverter based DVR. Each phase is controlled independently which offers mitigation of both symmetrical and asymmetrical sags. The proposed DVR employs the modified feedback control technique. The simulation results from MATLAB/Simulink environment verify the efficacy of the proposed DVR topology. The proposed DVR topology is suitable for mitigation of sags and swells initiating at any point-on-wave. � 2018 IEEE.