Single Phase Dynamic Voltage Restorer topology based on five-level ground point shifting inverter

A Single Phase Dynamic Voltage Restorer (DVR) based on five-level ground point shifting multilevel inverter topology has been proposed in this paper. The proposed inverter has a floating ground point. Therefore, by shifting the ground point, it is observed that the inverter circuit gives five output voltage levels from single DC voltage source. This configuration uses less number of switches compared to the existing multilevel inverter topologies. A fast sag swell identification technique using d-q reference frame is also discussed in this paper. This proposed topology of the DVR can compensate voltage sag, swell, flicker and maintain the required voltage at the load bus. The detailed simulation study is carried out using MATLAB/Simulink to validate the result.