Pulsé Panoramic Mont Blanc: an exceptional site for an exceptional renovation!

The Panoramic Mont-Blanc gondola lift, a mythical installation in the Mont-Blanc massif and soon sexagenarian, has decided to give itself a new lease of life in spring 2015.

This pulsed-type ropeway (a fixed carrying rope + a hauling rope) connects France to Italy from the Aiguille du Midi to the Pointe Helbronner, in a majestic setting, flying over the Vallée Blanche and the Glacier du Géant over an exceptional distance of more than 5 km and an average altitude of about 3600 m.

Its renovation was necessary to replace obsolete equipment and the Compagnie du Mont-Blanc wanted to increase its functionality and reliability, while preserving an extraordinary high mountain setting, attracting several thousand people a year.

The technical solutions chosen therefore contribute to purifying the site, thus meeting the need to integrate the installation into the site, while increasing the availability of the gondola lift by the redundancy of all its components, both those of the main motorization and those of the emergency one. In the end, the installation is simplified, its components are less exposed to atmospheric risks, thus eliminating many operating constraints.

The work site of the extreme

As the construction site took place during the winter period, the SEMER/POMA/JOLY&PHILIPPE teams took up a real technological challenge, working in capricious weather conditions. The SEMER electrical cabinets, located facing the rock in a cramped room above the station, had to be transported by hoist from the outside!

From an electrical point of view, the major advantage of the renovation was to remove the Ward LEONARD group dating from 1975, which manufactures direct current for the electric motor, which was replaced by an asynchronous motorization with AFE inverter. The AFE inverter has many advantages, including better energy control by returning energy to the grid, resulting in an overall reduction in electricity bills, a significant detail for the operator. This new motor requires much less maintenance (saving time and supplies, saving "clean" energy) and allows the gondola lift to be operated on a generator set.

But the subtlety of this renovation lies in the installation of a second asynchronous motorization with AFE inverter, instead of an IC engine and its hydraulic emergency drive: a real ecological progress by eliminating the use of petroleum products and its related constraints.

Moreover, thanks to this new emergency motor, if it were necessary to evacuate, the operation would take half as long as for a "normal" ropeway, a reassuring precision when considering the 5 km of line length!

Horsepower under the hood

The gondola lift is therefore taking a new lease of life with two completely identical electrical equipment, as safe in operating mode as in emergency mode.

The new automated system ensures smooth motor control, limiting jolts and considerably reducing the risk of rope crossings, providing comfort for passengers while maintaining an operating speed of 7 m/s. And if necessary, the oversizing of the main motor (260 KVA) enables to easily uncross the ropes.

Thanks to SEMER technology, the modernization also made it possible to install a remote control desk on the platform. The workstation has become more efficient and ergonomic, making the operating staff more available for its customers and avoiding him having to climb stairs several times a day; which the staff appreciate because at this altitude, sparing oneself is not a luxury!

New advantage in terms of availability: a radio link

Based on its experience in remote transmission, SEMER has implemented two redundant two-way radio links between the Aiguille du Midi and the Gros Rognon station, thus increasing the availability of the lift. Gone are the recurrent problems of wind factor on the old wired link, the radio link being 100% reliable. In addition, visual pollution is reduced by removing the cables of the safety line. According to Olivier CHAMEL, Chief Operating Officer of the Aiguille du Midi, “no breakdowns occurred throughout the summer season, which is very appreciable”. With this installation giving complete satisfaction, it is planned to extend this radio link between Gros Rognon and Helbronner by spring 2016.

Given the exceptional setting and extreme conditions in which they operated, the teams from CMB, DSCA, SEMER, POMA, JOLY&PHILIPPE and the STRMTG inspection services performed a real technical feat, pooling their experience, know-how and determination.

And to refine its rejuvenation, the modernization of the gondola lift continues with the replacement of the Helbronner return station and its rescue equipment on the Italian side.

The CMB has renewed its confidence in the same players for an operational use scheduled for spring 2016.