Summary
The impact of negative and positive strokes on the lightning performance of HVAC and HVDC transmission lines due to backflashover is assessed based on results provided by systematic computational simulations with typical configurations of 500 kV transmission lines. Traditional cumulative peak current distributions of negative first, subsequent, and positive strokes were assumed, along with representative current waveforms of such events. The obtained results indicated that lightning outage rate is mainly defined by negative first strokes, and that the contribution of subsequent strokes and positive strokes on such rate becomes relevant just for low values of tower-footing grounding resistance. Furthermore, the contribution of subsequent strokes is slightly more important for the performance of the HVAC line, whereas the contribution of positive strokes is much more significant for the performance of the HVDC line.
Read more Read lessThe developed quantitative analyses indicated that subsequent strokes and positive strokes may impact the outage rate of those lines with grounding resistance of 20 and below installed in regions under moderate to high ground flash density (around of 5 flashes/km2/year or greater), resulting on outage rates superior to 1 outage/100 km/year.
Additional informations
| Publication type | Session Materials |
|---|---|
| Reference | C4_11087_2026 |
| Publication year | |
| Publisher | CIGRE |
| Country | Brazil |
| Study committees |
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| File size | 1,020 KB |
| Price for non member | 30 € |
| Price for member | 30 € |
Authors
SILVEIRA Fernando H. - UFMG University Brazil; ZAGO Giovanna M.P. - UFMG University Brazil; BUENO Gabriel A. - UFMG University Brazil
Keywords
Backflashover, HVDC transmission line, Lightning performance of transmission lines, Negative and Positive lightning strokes, Severe thunderstorms
