Novel Sensor System for Leakage Current Detection on Insulator Strings of Overhead Transmission Lines

Abstract

We report the development of a measurement system capable of monitoring and characterizing the main features of the leakage current flowing on a polluted insulator string of a high-voltage transmission line. The system comprises a fiber-optic sensor, directly connected to one insulator of the string, that emits a sample of the leakage current waveform to a processing module via an optical link. A capacitive sensor connected to the processing module allows recording the relative humidity of the outer environment. At the present stage, six measurement units have been deployed on CHESF's electrical transmission system in the Northeast of Brazil, and studies are underway to further correlate the degree of environmental pollution with humidity and leakage current activities on high-voltage insulator strings.

A Wireless System for Monitoring Leakage Current in Electrical Substation Equipment

“…In heavily polluted areas, the conduction increases due to contamination by wetted salts and other conducting particles. The installation of leakage current sensors on lines and substations located in these areas can be very useful for monitoring the pollution severity and the surface condition of insulators [27][28][29].…”

Sensoring Leakage Current to Predict Pollution Levels to Improve Transmission Line Model via ANN

“…Several techniques have been proposed in the literature to measure the quantity of pollutants deposited on an insulator surface, such as measurement of equivalent salt deposit density (ESDD), determination of non-soluble deposit density (NSDD) and measurement of surface resistance (SR) [5]. This paper presents a correlation study comparing information obtained from the optical sensor network, the traditional visual inspections performed by CHESF's maintenance team [6].…”

Detection of Critical Conditions in Ceramic Insulators Based on Harmonic Analysis of Leakage Current

“…Moreover, there are variety methods in which detection of the insulator conditions and prediction of flashover have been considered [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. In [9], peak amplitude changes of the leakage current has been assumed as a criterion to detect the critical conditions in insulators.…”

“…In this respect, many authors have examined how to predict flashover in the composite insulator [12][13][14]. In [15], flashover has been predicted by using the optical sampling of leakage current signal. In this paper, an optical monitoring system that stores relevant information of the leakage current have been developed.…”