Mitigation of Voltage sag and swell by using DVR

Voltage sags and harmonics disturb the power quality and this can be overcome by custom power device called Dynamic Voltage Restorer (DVR). The DVR is normally connected between the source or feeder and critical or sensitive load. The performance of DVR depends on the efficiency of the control technique involved in reference signal generation considering phase angle jumps. The control technique shall compensate the voltage disturbances and shall reject the load current disturbance. If voltage regulation is high, disturbance rejection ability decrease and vice versa Hence a robust and optimal control technique is very much required to compromise between voltage regulation and disturbance rejection. The work is focuses on implementation of various control techniques with suitable voltage source converter topology for proper voltage regulation and disturbance rejection.