Summary
The supporting insulator is one of the most important parts in SF6 gas insulated switchgear (GIS). Flashover of supporting insulators would cause serious harm to the electrical system. Nowadays, with the rapid development of GIS, flashover characteristics of supporting insulators in GIS have attracted wide attention of lots of researchers. According to the previous research, it is found that metallic particles on the surface of supporting insulators have significant effect on flashover characteristics. However, the influence is not studied clearly, and agreements on the mechanism of flashover have not been reached, neither. This paper clarifies the influence of the position of defect and gas pressure on flashover characteristics. Possible explanations for those phenomena are given. A research platform for flashover characteristics of 72.5kV supporting insulators with metallic particles on surface was constructed.The results showed that the flashover voltage of the insulator with no defect under VFTO is higher than that under SLI. The flashover voltage drops obviously when the metallic particle was attached to its surface, and the flashover voltage becomes lower when the metallic particle was affixed closer to the high-voltage electrode. This phenomenon is related to the accumulation of space charge, and a streamer-leader model is established to explain it. The flashover voltage increases with the SF6 pressure ranged from 0.1MPa to 0.4MPa under SLI, but the flashover voltage-pressure curve is like a hump under VFTO.
Additional informations
| Publication type | ISH Collection |
|---|---|
| Reference | ISH2015_417 |
| Publication year | 2015 |
| Publisher | ISH |
| File size | 729 KB |
| Price for non member | Free |
| Price for member | Free |
Authors
MacGregor, Sedlacek Jan, Plesch Juergen, Scharnholz Sigo, Pack Stephan, Wakimoto Toru, Coleman, Aquiles-Perez, Tamakoshi, Kubo
