An improvement of voltage quality in low voltage distribution system using dynamic voltage restorer

With the increase use of semiconductor devices (switched mode power supply) and ICT (information communication technology) equipment in homes, offices and the industry's power quality (PQ) are gaining significant interest to both the electric utility and the industry. The absence of power quality causes enormous economic losses all over the world; it is estimated that these problems cost commerce and industry about 100 billion Euros per annum in the European Union. This paper is, therefore, aimed at mitigating power quality problems such as voltage sag, voltage swell, voltage unbalance and harmonic at low voltage distribution system, using a dynamic voltage restorer (DVR). Implementations of DVR have been proposed at both a medium and low voltage levels to protect sensitive loads from power quality problems. The proposed system is designed using Matlab/Simulink Sim Power System tool box. The simulation results verified the capability of the proposed DVR system in mitigating the power quality problems in a lowvoltage distribution system.