Name of OHTL

Arbois - Le Bouchaud - Gysserie - FRANCE

Voltage of OHTL



Efla electrical engineering

Duration of assignment

08.2008 - 02.2009

Value of service

53 k€

The aim of this project was the study of the improvement of the electricity quality of a 63kV OHTL having frequent outages due to lightning impacts. The target was a number of defects lower than 5 per 100km of line.

Various technical solutions have been tested, being:
- Installation of earth wire
- Installation of sure arrester at specific locations to be determined
- Increase of Insulation of the line
- Improvement of tower's earthing
Prior to the studies, a site visit has been done by HECLA to check the suitability between documents and line, to ensure future feasibility of the proposed solutions, detect possible structure defects and identify tower generations.

In parallel, HECLA carried out a soil resistivity and tower's earthing resistance measurement campaign with ground resistance test equipment (Telluromètre Chauvin Arnoux CA 6470).

All solutions have been tested by HECLA's engineers by using the OHTL calculation software PLS-Cadd (POWERLINE SYSTEM Inc.). A technical and financial analysis has been performed in order to select the best solution.

Our partner EFLA assisted us for electrical studies of improvement of tower's earthing system and for determination of type and locations of surge arresters.