Hygroscopic properties of pollutants on HV insulators

Author

Chrzan, Krystian ; Pohl, Zbigniew ; Kowalak, Tomasz

Author_Institution

Tech. Univ. of Wroclaw, Poland

Volume

24

Issue

1

fYear

1989

fDate

2/1/1989 12:00:00 AM

Firstpage

107

Lastpage

112

Abstract

The mechanisms of moisture absorption by an insulator surface contaminated with different salts is described. A list of some salts depending on their hygroscopicity is given. Measurements of surface conductivity and leakage current on flat insulator models at different relative humidities and with different types of salt were carried out. At natural atmospheric conditions, the flashover voltage of cap and pin insulators subjected to 250/2500 μs switching impulses was evaluated. It is shown that the intensity of moisture absorption on insulator surfaces depends upon the chemical constitution of the pollution. The effect of intense and continuous moisture absorption can cause long-lasting surface discharges at operating voltage or can be a reason for flashovers a short time after the voltage has been switched on to a line

Keywords

air pollution; chemisorption; electric current measurement; electrical conductivity measurement; flashover; high-voltage engineering; insulation testing; insulators; leakage currents; surface conductivity; surface discharges; HV insulators; cap insulator; chemical constitution; flashover voltage; flat insulator models; hygroscopicity; insulator surface; leakage current; moisture absorption; pin insulators; pollution; salts; surface conductivity; surface discharges; Absorption; Atmospheric measurements; Conductivity measurement; Flashover; Insulation; Moisture; Pollution; Surface contamination; Surface discharges; Voltage;

fLanguage

English

Journal_Title

Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

0018-9367

Type

jour

DOI

10.1109/14.19874

Filename

19874