Backflashovers of Transmission Lines Due to Subsequent Lightning Strokes

Author

Silveira, Fernando H. ; Visacro, Silverio ; De Conti, Alberto ; de Mesquita, C.R.

Author_Institution

Lightning Res. Center, Fed. Univ. of Minas Gerais, Belo Horizonte, Brazil

Volume

54

Issue

2

fYear

2012

fDate

4/1/2012 12:00:00 AM

Firstpage

316

Lastpage

322

Abstract

Lightning overvoltages across insulator strings of existing 138- and 69-kV transmission lines were simulated using the hybrid electromagnetic model. It was found that, though the reduction of tower-footing grounding resistance is very effective to decrease lightning overvoltages caused by first strokes, this reduction is saturated around 750-600 kV for typical currents of subsequent strokes. The lightning performance of these lines was estimated and subsequent strokes were found to be relevant cause of backflashovers in 69-kV lines.

Keywords

earthing; flashover; insulators; lightning protection; power transmission lines; power transmission protection; backflashovers; hybrid electromagnetic model; insulator strings; lightning overvoltage; lightning strokes; tower-footing grounding resistance; transmission lines; voltage 138 kV; voltage 600 kV to 750 kV; voltage 69 kV; Grounding; Insulators; Lightning; Poles and towers; Power transmission lines; Resistance; Surges; Lightning parameters for engineering application; lightning overvoltage; lightning performance of transmission lines; subsequent strokes;

fLanguage

English

Journal_Title

Electromagnetic Compatibility, IEEE Transactions on

Publisher

ieee

ISSN

0018-9375

Type

jour

DOI

10.1109/TEMC.2011.2181851

Filename

6144002