Measurement of the Evolution of Dripping Water Conductivity of an Ice-covered Insulator During a Melting Period

This paper deals with the measurement of the evolution of the water conductivity dripping from an ice-covered insulator during a melting period. For this purpose, post type insulator covered by a wet-formed ice deposit was submitted to melting period tests leading to flashover. During each melting period, leakage current, applied voltage and dripping water conductivity were recorded simultaneously. To measure with precision the conductivity of dripping water, a system of measurement in real time based on a Plexiglas cell was developed. It was demonstrated that dripping water conductivity reaches its maximum value before the occurrence of flashover. For each flashover test performed under the same experimental conditions, the conductivity of the dripping water presents a similar evolution. These results will be helpful to understand the dynamic behavior of ice-covered insulator flashover thus contributing to increase the reliability of flashover numerical models.