Client

RTE

Name of OHTL

Curbans - Sisteron - FRANCE

Voltage of OHTL

225kV

Partners

Ingedia Bep topographical survey

Duration of assignment

04.2010 - 12.2010

Value of service

50 k€


The aim of the project was to study the connection of the 33MW Curbans PV Power Plant to the existing 225kV OHTL.

To do so, it has been decided to replace an existing tower by a new one allowing the connection of the PV Power Plant to the single circuit existing OHTL with a triple point.

Various technical constraints had to be taken into account by HECLA's engineers, such as the obligation to keep the horizontal arrangement of conductors due to clearance matters under ice jumping loading, and a limited area for setting up of the new tower.

The solution brought by HECLA's team consisted in erection of a tower type M1 with cross arms arrangement type M8, composed of a upper beam for the main line and additional cross arms located at the top of the body for the PV Power Plant line, with a specific orientation compared with the existing line axis to ensure clearances respect.

All mechanical strengthening and clearance calculations have been carried out by HECLA's engineers, by using PLS-Cadd software (POWERLINE SYSTEM Inc.) A specific study regarding earth wire cross arms have been performed in order to check their mechanical strengthening, one of them being equipped with four earth wires to ensure appropriate lightning protection. A numerical model has been realized by HECLA with our latticed steel structures calculation software (TOWER - POWERLINE SYSTEM Inc.)

Key figures:
Height of ground at tower location: 1053m, ice area of 4cm (diameter of ice on cables), 19 T of steel.