Minimum requirements for rapid voltage changes regulation based on their effect on flicker

The definition and the method to characterize a rapid voltage change (RVC) are defined in the standard IEC 61000-4-30. Other standards, such as IEC 61000-3-7, IEC 61000-2-12 or EN 50160, limit the number and magnitude of RVCs for compatibility level or for planning levels in medium and low voltage public supply systems. Those limits control the effect of RVCs on light flicker. This work analyses the effect of the magnitude and rate of change of voltage of RVCs on light flicker through the study of the flicker perception obtained by means of an IEC flickermeter. The work was performed using simulated RVC waveforms and also through real voltage waveforms recorded in a low-voltage distribution network in Spain. The results show that RVCs have a greater influence than had been reported in previous studies which were based on subjective tests. The limits established by the standards leave margin for RVCs to produce enough flicker to be annoying.