Stability conditions and erosive action of arcs at insulator surface
Abstract
The flashover voltage of an insulator depends on the state of the insulator surface. The conducting layer which can cover the insulator (humidity, dust) provokes and generates surface discharges. Two processes can occur: either an instable process with development of an arc leading to flashover, or slow process with small arcs propagating at the insulator surface and provoking an erosion when the surface material is a polymer. The comparison between theoretical and experimental data evidences measured flashover voltage twice as high as calculated values. An experimental device localizing small arcs on a determined zone of an insulator was developed and applied to the study of cylindrical bar synthetic resin insulators subjected to a known electric field. The contamination is obtained by salted water pulverization. The influence of parameters such as resin nature, additive nature, nature, form and granolometry of loads, on the erosion due to the surface arcs was evidenced.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- 1976
- Bibcode:
- 1976STIN...7820426R
- Keywords:
-
- Electric Arcs;
- Electric Discharges;
- Insulators;
- Synthetic Resins;
- Electrical Insulation;
- Electrolytes;
- Equivalent Circuits;
- Erosion;
- Flashover;
- Stability;
- Surface Reactions;
- Electronics and Electrical Engineering