Rapid Voltage Change (RVC)
A rapid voltage change is a fast rise or fall of the RMS voltage. This can be caused by the switching on of a specific load or by a sudden change in source voltage. Sudden source voltage changes can occur in solar grids when the sun is obscured by clouds. Source voltage changes can also occur in wind farms when then wind speed decreases. Load switching can cause a rapid voltage change if the rating of the load is a significant fraction of the fault level of the supply voltage.