Development and Simulation of DynamicVoltage Restorer for Voltage SAG Mitigationusing Matrix Converter

Dynamic Voltage Restorer (DVR) is a series connected custom power device, which is often used for line side conditioning especially for voltage sag and swell restoration and hence improves power quality. DVR can be considered to be cost effective when compared with other compensation devices. But the use of DC link capacitor in the conventional DVR will increase the size, weight and the cost of the entire system which inhibits widespread use of DVR. This paper brought forward a matrix convertor (MC) based voltage source inverter for conventional DVR to enhance capability of DVR for efficient voltage restoration. This paper also presents a new control circuit topology for the mitigation of wide variety of voltage disturbances affecting critical loads such as voltage sag. The DVR used here is based on a three-phase to single-phase direct ac/ac converter energized from the main grid, known as Matrix Converter, characterized by the elimination of energy storage elements and dc link capacitors. This, in turn, leads to the compensation of long time voltage sag and the reduction of size, weight and cost of the entire system. This method is based on the minimum error between the real and the forecasted output voltages. Simulations are carried out in MATLAB/SIMULINK software package.