Mitigation of Voltage Sags by Dynamic Voltage Restorer

Abstract

Voltage sag is the most severe type of power quality disturbance faced by many commercial and industrial customers. The proliferation of voltage sag load equipment used in industrial plants may cause tremendous economic and financial losses up to millions of dollars attributed to a single disruption. Therefore, it is very important to mitigate the impact of voltage sags on sensitive equipment. In this paper, Dynamic Voltage Restorer (DVR) is used to mitigate the voltage sag during fault condition. DVR is considered to be the most efficient and effective mitigation device. The method to calculate the DVR devices for the fault calculation, were consider in this paper, as well as the control strategy. The mitigation technique was applied to an IEEE 30-buses electrical network to illustrate its application.The results show that the mitigation technique is able to mitigate voltage sag. Analyses of the voltage sag magnitude had shown the different with and without DVR for the network system. 