Re-commissioning the control-command unit

The servicing of the Fionnay facility’s installations was no quick or easy feat. The plant’s six Pelton 48MW units were all serviced between 2008 and 2013, together with their control-command. Later, between 2016 and 2022, the pressure pipes of the Dix-Fionnay-Nendaz-Rhône’s drop were inspected and reinstated. The overhead penstock of the Peroua-Condémines section was renewed. The Fionnay and Nendaz plants had to be stopped during this time, and some of their components were disconnected from the power source and shut down. 

Software and firmware updated

This did not apply to the control unit, which remained energised but had to be put back into service before everything was reconnected to Swissgrid’s transmission grid. A task Grande Dixence SA entrusted to HYDRO Exploitation. It was a Herculean challenge, both from a technical standpoint and that of managing the required ressources.

Control-command units with already partially used life-cycles had to be verified and adpated. We also interfaced original systems with systems set up more recently. Finally, several migration processes were required to update the software/firmware that hadn’t been updated since 2016.

Friendly collaboration with DransEnergie

As for resources, we were able to rely on experienced professionals, who were happy to work for our company, since some of those present this year were also involved in the initial commissioning in 2008. Being able to swiftly establish a sound collaboration plays a vital role in ensuring the successful outcome of this kind of project. In this case, thanks to our friendly collaboration with the local company DransEnergie, we were able to draw on additional skills, and thereby ensure the completely safe recommissioning of the plant.