Review on voltage sag studies for distribution grid including renewable energy sources

Several types of power quality problems can be observed in power network. These power quality problems include voltage unbalance, voltage flicker, voltage sags and swells, interruptions, and voltage and current harmonics. Voltage sag is one of the vital power quality issues. This problem can cause a decrease in power grid voltage over a short time horizon. The aforementioned problem is caused by various types of short circuits and the widespread use of sensitive devices. These problems have a significant impact on power systems. In this review article, the different ways to prevent voltage sag have been presented by considering literature studies. Concerning voltage sags in radial and mesh grids, the equipment used, and methods have all been taken into account. In these studies, the articles about voltage sag-related problems have been put into groups based on certain criteria. These criteria include the consideration of uncertainties in electricity demand or renewable sources. The recommendations related to the voltage sag studies have been presented. These suggestions are based on the inclusion of electricity consumption and renewable energy source uncertainties. The future works have been mentioned by considering these load and renewable system uncertainties.