Dynamic Voltage Restorer Using Direct ac/ac Converter with Fictitious dc Link

In this paper, a new topology for a three-phase DVR is proposed. The proposed topology uses direct three-phase to three-phase converter with fictitious dc link. As a result, the proposed topology does not require any energy storage element. The proposed topology can protect the sensitive loads against several types of voltage disturbances such as balanced and unbalanced voltage sags and swells and voltage flicker. This topology has less volume, weight and cost due to the elimination of energy storage elements. The proposed topology will not face any problem in long time compensation due to the fact that provides its required energy directly through the grid. The simulation results based on PSCAD/EMTDC software verify the capabilities of the proposed DVR in voltage disturbances compensation.

Keywords:

DVR , Voltage Sags , Voltage Swells , Voltage Flicker , Direct ac/ac converter