XFLEX HYDRO

The H2020 XFLEX HYDRO project aims to demonstrate that modern hydropower plants can enhance today's power grids, which are increasingly dependent on intermittent renewable energy, by integrating innovative technologies. The XFLEX HYDRO technologies, each of which is being demonstrated in hydroelectric power plants in Europe, include the ability to run machines at variable speed, pump and turbine at the same time, or use batteries to adjust the production and consumption of the facilities.  

Among the seven power plants selected, the HES SO Valais team is carrying out the numerical simulations and part of the on-site tests for four demonstrators; the Z'Mutt pumped storage power plant (Grande Dixence, Switzerland), the Alto Lindoso and Caniçada storage power plants (EDP, Portugal) and the Grand Maison pumped storage power plant (EDF, France).

Z’Mutt, Grande Dixence, Switzerland

This Grande Dixence pumping station will be equipped with a new variable speed pump-turbine with a full power converter. Numerical simulations, and tests directly on the prototype, carried out by the HES SO Valais, will make possible the prediction of the gain in terms of fatigue during the start-up and shutdown phases in turbine or pump mode and during the transitions for various scenarios using the variable speed technology.

Numerical simulation of the flow and prediction of the stresses on the impeller during a starting sequence in turbine mode. Daniel Biner

  

Grand Maison, EDF, France

The Grand-Maison hydroelectric scheme, located in Isère in the French Alps and operated by EDF, is the most powerful pumped-storage station in Europe with a capacity of 1,800 MW. The objective of this project is to implement a hydraulic short-circuit operation mode, i.e. a simultaneous operation of pumps and turbines. This mode allows to regulate the energy consumed by the pumps with the help of the Pelton turbines and thus to provide a regulation service to the electricity network operator. The numerical simulations of the flow, carried out by the HES SO Valais, will predict the possible instabilities which can develop in the bifurcations or trifurcations as well as the losses of load to select the most advantageous scenarios for the owner while limiting the risks.

Visualization of vortices at a bifurcation in hydraulic short circuit configuration. Jean Decaix.

 

Alto Lindoso andCaniçada, EDP, Portugal

The Alto Lindoso hydroelectric storage power plant, located in northern Portugal along the Lima River, is equipped with two turbines for a total capacity of 630 MW. The turbines rotate at a speed of 214 revolutions per minute for a total flow of 250 m3/s. For this demonstrator, as for the Caniçada power plant, numerical simulations of fluids and structures are carried out by the HES SO Valais to evaluate the effect of variable on the extension of the operating range.
Current lines in no-load condition. (right) FEM analysis of the Alto Lindoso wheel. Olivier Pacot.

Partners

• Alpiq

Publications

• Biner D, Pacot O, Decaix J, Münch-Alligné C (2022), «Plus de flexibilité grâce aux simulations », Bulletin ElectroSuisse 2, 2022
  
  
• Decaix J, Biner D, Drommi J-L, Avellan F and Münch-alligné C (2021), "CFD simulations of a Y-junction for the implementation of hydraulic short-circuit operating mode", IOP Conference Series: Earth and Environmental Science., jun, 2021. Vol. 774(1), pp. 012013. IOP Publishing.
  
  
• Alligné S, Béguin A, Biner D, Münch-Alligné C, Hasmatuchi V, Hugo N, Avellan F, Dujic D and Nicolet C (2021), "Turbine mode start-up simulation of a FSFC variable speed pump-turbine prototype – Part I: 1D simulation", IOP Conference Series: Earth and Environmental Science., jun, 2021. Vol. 774(1), pp. 012052. IOP Publishing.
  
  
• Biner D, Alligné S, Hasmatuchi V, Nicolet C, Hugo N, Avellan F, Dujic D and Münch-Alligné C (2021), "Turbine mode start-up simulation of a variable speed Francis pump-turbine prototype – Part II: 3-D unsteady CFD and FEM", IOP Conference Series: Earth and Environmental Science., jun, 2021. Vol. 774(1), pp. 012070. IOP Publishing.
  
  
• O. Pacot, T. de Colombel, C. Segoufin, J. Delannoy, S. Leguizamon, J. Delgado, M. Roque, C. Münch-Alligné, 2021, “Effect of the variable speed on the hydraulic behavior of the Caniçada Francis turbine.”, SimHydro 2021.
  
  
• D., Biner, P. Bontemps, D., Dujic, C. Münch-Alligné, 2021 “Discretization Uncertainties of Flow and Fatigue Damage Simulations of a Reversible Francis Pump-Turbine at Off-Design Operation in Turbine Mode”, SimHydro 2021.