Protection of DVR against Short Circuit Faults at the Load Side

An additional control scheme has been proposed in this paper for a dynamic voltage restorer (DVR), to protect it against load short circuit conditions. When overcurrents occur in the distribution system, under the proposed scheme the DVR reverses its injected voltage polarity so as to minimise the current flow. The detection method is based on impedance measurement feedback. The advantage of the scheme is that no additional over current device or protection is required for the DVR and it is easy to implement. The proposed control scheme has been validated through simulation.