Izvorni znanstveni članak

Line Arrester Application on a 110 kV High Alpine Overhead Line to reduce Lightning-Caused Outages

T. Judendorfer ; Graz University of Technology, Inffeldgasse 18, 8010 Graz AUSTRIA
S. Pack ; Graz University of Technology, Inffeldgasse 18, 8010 Graz AUSTRIA
M. Muhr ; Graz University of Technology, Inffeldgasse 18, 8010 Graz AUSTRIA

Sažetak

This contribution discusses a project, which aims to increase the reliability in an existing
110 kV overhead transmission network by taking measures addressing lightning and
grounding issues. Due to the fault statistic in the past, a single overhead line was identified as
a main reason for the lightning-caused outages in the area. In this work a number of
possibilities for the reduction of lightning-caused outages are discussed and the measures
taken in the network are described. All considerations took the special geographical situation
of 2300 meter above sea level, the grounding resistance of up to 1200 Ohm and the local
lightning activity of more than 6 lightning strikes per km² and year into account (4 to 5 times
higher than in other Austrian regions).
An analytical process was carried out to evaluate relevant parameters and to develop a
concept of practical measures. Within these evaluations, the footing resistance, the
effectiveness of the shielding angle of the shielding wires and the line arrester locations were
analyzed. A multiplicity of numerical calculations were performed to assess the application of
surge arresters regarding the insulation coordination for the system. To improve the line
performance and to decrease the line outage rate, a number of practical measures were applied
to the 110 kV line. In the past, the double three phase systems of the 110 kV overhead line
was constructional converted into one active single three phase system with two additional
earth wires. According to the numerical results, 18 surge arresters have been installed in a line
section of 9 towers, located in a high alpine part and in an area of high lightning activity.
Three years of field experiences have shown that the theoretical investigations and the
practical measures led to a significant decrease of lightning caused outages.
In the year 2007 a new project was started to evaluate a reconstruction of the line into the
original double three phase system. New numerical calculation routines were made to apply
line arresters at this important 110 kV system in an Austrian extreme mountain region. Based
on this results, a new application of line arresters and the constructional change of the system
is planned.

Ključne riječi

Line surge arresters; 110 kV overhead line; high alpine region; lightning outages; backf

Hrčak ID:

198505

URI

https://hrcak.srce.hr/198505

Datum izdavanja:

20.6.2017.

Posjeta: 369 *