Paper Title
Voltage Sag Compensation using Dynamic Voltage Restorer

Abstract
This Paper describe & demonstrate the effect of PI Controller in a novel design of a Dynamic Voltage Restorer (DVR), Which can reduce the power quality problems like sag, swell & phase jumps by injecting less active power in a system & provide the same rate of power at load side without any disturbance by using PI controller the design of DVR presented here include the combination of SPWM based control scheme &abc to dq0 Transformation techniques is used in the controller or control circuit. This also helps to minimize the power quality problems & voltage sags. In this Sequence get the knowledge of this control system of DVR MATLAB/SIMULINK atmosphere was used. The result of this complete system of DVR control scheme with PI Controller & DVR Control system without PI Controller. This clearly shows its completely successful compensation of voltage sags problem & power quality problems by injecting very little active power. Index terms - DVR, PI, SPWM, PLL, VCO.