On the detection of Rapid Voltage Change (RVC) events for power quality monitoring

In the last edition of the IEC Standard 61000-4-30 a Rapid Voltage Change (RVC) is defined as “a quick transition in RMS voltage between two steady-state conditions, during which the voltage does not exceed the dip/swell thresholds [1].” Because of their intrinsically sudden nature, RVC-like events are generally hard to detect and to monitor. In fact, no clear criteria to set the detection thresholds are defined at the moment. Certainly, threshold selection should take into consideration measurement uncertainty. In this respect, in this paper the uncertainty of the classic RMS estimator suggested in the IEC Standard 61000-4-30:2015 during an RVC event is evaluated both analytically and through simulations. The presented analysis paves the way to reasonable criteria (and limits) to detect RVC-like events in realistic scenarios.