Accurate estimation of grid phase angle and magnitude is important for effective operation of Dynamic Voltage Restorer (DVR). Under unbalanced voltage sags, the estimated output voltages of a conventional SRF-PLL contain a second harmonic ripple which makes it difficult to control DVR. In this paper a DSOGI pre-filter based PLL is employed to extract the symmetrical components of the grid voltage and eliminate the double frequency ripple from the estimated dq-voltages. The mathematical model of DSOGI-PLL and DVR control is presented. A simple single loop dual sequence control with PI controller in the voltage loop is implemented in synchronous reference frame to track the DVR reference voltages. Resonant controllers are added to eliminate fifth and seventh harmonics from the load voltage. Simulation studies are carried out in PSCAD/EMTDC to evaluate the performance of the 10KV DVR system under various voltage disturbances such as asymmetric, symmetric voltage sags and harmonics. The obtained results validate the effectiveness of the DSOGI pre-filter based control scheme.