Verification of a new energy control strategy for dynamic voltage restorer by simulation

To restore the load voltage, dynamic voltage restorer (DVR), which installed between the supply and a sensitive load, should inject voltage and active power from DVR to the distribution system during voltage sag. Due to the limit of energy storage capacity of DC link, it is necessary the minimize energy injection from DVR. In this paper the techniques of the supply voltage sag compensation in a distribution feeder are presented. In addition, a new concept of restoration technique is suggested to inject minimum energy for a given apparent power of DVR. Simulation results carried out by PSCAD/EMTDC1, verify the efficiency of the proposed method.