Leakage Current Monitoring of Suspension Insulator for Effective Determination of ESDD

Leakage current contains significant characteristics of a polluted insulator. With the increase in pollution the magnitude of leakage current increases. Equivalent Salt Deposit Density (ESDD) is a popular parameter for the estimation of the severity of pollutants. However, the measurement of ESDD involves costly equipment and requires samples directly from the surface of suspension insulator. It is a tedious task to collect a sample from the surface of the suspension insulator under operation. In the present work, a methodology has been proposed to estimate the contamination level severity parameter, ESDD using Detrended Fluctuation Analysis (DFA) on recorded leakage current data. In the present work, NaCl, Kaolin, and water are used to emulate the artificial pollutant layer on an 11 kV suspension insulator disc. It is observed that the DFA parameter maintains a well-defined relationship with ESDD and conductivity.