Modified Method of Detecting Rapid Voltage Changes in a Medium Voltage Network

In this paper, medium voltage data from four locations are analyzed for rapid voltage changes (RVCs). The definition of an RVC event given in IEC 61000-4-30 is altered to investigate how the results of an analysis changes. The alterations made to the RVC definition are the RVC threshold and the number of half-cycles required for stability. It is shown that a certain change in the definition will not necessarily affect the results in the same way for data obtained at different locations. One important conclusion is that changing the definition of an RVC can lead to an initial steady-state not being found within a measurement, thus giving zero RVCs in the results. It is therefore of great importance to take this into consideration so as not to incorrectly assume that the alteration made to the definition makes the data appear more stable to the detection algorithm. The motivation for this work is to show that an RVC event is not a black-and-white concept but is highly influenced by revisions to its formal definition.