On Fusing Mechanism Involving the Fuses at Secondary Winding of PT Induced by VFTO
Abstract
The impact of very fast transient over-voltage(VFTO) on the primary and secondary equipment in gas insulated station(GIS) should not be ignored. In this paper, the research on fusing mechanism involving the fuses at secondary winding of PT induced by VFTO is carried out based on an actual case from the 500kV GIS substation belonged to Guizhou Tianshengqiao No.2 hydro power plant. As for the high voltage side, the transfer function about over-voltage can be formed in order to analyse the characteristics about high frequency over-voltage. As for the low voltage side, a three-phase equivalent model for secondary circuit of PT with the parallel arrangement at the A, B and C phases may be built for simulating the current distribution of the low voltage fuses in the situation of high frequency voltage and current. The results show that the maximum allowable current of fuse might be reduced greatly in the high-frequency circumstance due to skin effect and proximity effect, in comparison with nominal frequency condition.
- Publication:
-
IOP Conference Series: Earth and Environmental Science
- Pub Date:
- October 2017
- DOI:
- 10.1088/1755-1315/86/1/012032
- Bibcode:
- 2017E&ES...86a2032M