Title :
An evaluation of surface behaviour of insulating materials in presence of decomposed SF6
Author :
Centurioni, L. ; Coletti, G. ; Guastavino, F. ; Tommasini, D.
Author_Institution :
Dept. of Electr. Eng., Genoa Univ., Italy
Abstract :
A testing procedure for screening candidate epoxy systems for spacers in SF6-insulated HV (high-voltage) devices is presented, and some data on the behavior of varnished and unvarnished specimens are reported. The lack of difference in the surface resistance during and after exposures to vapors of three different HF+water solutions has been confirmed. A comparison with the behaviour of the same materials during and after attack by decomposed SF6 gases suggests that the damage penetration depth is a parameter better correlated with the resulting material variation than the decrease in surface resistance during the exposure tests. The protective role of varnish in the HF attack was demonstrated by damage penetration depth and surface resistance measurements, complemented by optical microscope observation of morphology changes
Keywords :
corrosion testing; gaseous insulation; insulation testing; organic insulating materials; polymers; sulphur compounds; surface conductivity; HF-H2O; damage penetration depth; decomposed SF6 gases; epoxy systems; high voltage devices; insulating materials; optical microscope observation; surface behaviour; surface resistance; varnish; Gases; Hafnium; Insulation; Materials testing; Optical materials; Optical microscopy; Protection; Surface morphology; Surface resistance; System testing;
Conference_Titel :
Conduction and Breakdown in Solid Dielectrics, 1989., Proceedings of the 3rd International Conference on
Conference_Location :
Trondheim
DOI :
10.1109/ICSD.1989.69216
