An analytic model to simulate electrical behavior of snow deposited on a HV insulator

摘要

This paper aims to study the electrical behavior of snow for the purpose of developing an analytical model. Laboratory tests on a snow-covered polymer insulator string were carried out under high alternative voltage. The voltage-current characteristics of snow were analyzed, showing that voltage across snow is a logarithmic function of leakage current depending on snow density and melted conductivity. It was also found that voltage across snow is almost in phase with the leakage current through it. However, the obtained results show that snow resistance decreases as voltage across it increases. An analytical relation between applied voltage and the current flowing through snow as a function of density and conductivity of water melted from snow is derived. There is good correlation between analytical and experimental results.