Interpretation of RVM measurements, beyond the polarisation spectrum

Abstract

Much has been said about the reliability and interpretation of recovery voltage method (RVM) measurements. It has been shown in literature that the RVM method can be used to detect local moisture ingress in transformers, but also it has been shown that the old interpretation of the 'dominant time constant' has been found wanting. An important failure of the 'dominant time constant' interpretation is that it both focusses the user on a too simple interpretation and neglects data on other quantities that have also been recorded during this measurement. This paper deals with the all quantities that are recorded during an RVM measurement and shows how to use them so that they can form the basis of a better way to interpret RVM measurements.