Hydraulic Phenomena Frequency Signature of Francis Turbines Operating in Part Load Conditions

28th IAHR symposium on Hydraulic Machinery and Systems

Bouajila, S.^1 ; De Colombel, T.^2 ; Lowys, P.-Y.^2 ; Maitre, T.^1

Laboratoire LEGI, Domaine Universitaire, BP53, Grenoble, Cedex 9

38041, France^1

General Electric Hydro, 82, Avenue Leon Blum - BP 75, Grenoble Cedex 9

38041, France^2

关键词: Electricity grids;    Frequency signatures;    Integration of renewable energies;    Measurement campaign;    Off design condition;    Part load conditions;    Spatial harmonic;    Unsteady phenomena;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/49/8/082001/pdf
DOI  :  10.1088/1755-1315/49/8/082001

来源: IOP

【 摘 要 】

With the integration of renewable energies into the electricity grid, new requirements have been defined by power station operators. These changes bring new challenges for hydraulic turbine manufacturers, such as more flexibility during machines operation. In recent years, investigations have been focused on off-design conditions, since unsteady phenomena occur far from the classical Francis turbine operating range. This is especially the case at partial load, where dynamic stresses on the runner could impact the machine lifetime. The main objective of the study presented in this paper is to gain a better understanding of Francis turbine partial load flows. Thus, different runners are compared, based on test rig measurement campaigns already realized on model scale turbines. Pressure sensors and strain gauges signals are compared, using Fast Fourier Transform (FFT) analysis and Spatial Harmonic Decomposition (SHD). Finally, an attempt to classify these sets of frequencies is realized, according to their dynamical loading on the structure operating in off- design conditions and their impact on the turbine lifetime.