Abstract

Variable speed hydroelectric units equipped with full size frequency converter (FSFC) offer high operational flexibility enabling fast operating point transitions which increase grid regulation capacities. The XFLEX HYDRO H2020 European research project aims to demonstrate flexibility of such technology at prototype scale. The Z’Mutt pumping station, part of the Grande Dixence hydroelectric scheme located in Switzerland, is one of the demonstrators focused on the FSFC technology with a new 5 MW reversible Francis pump-turbine which will be commissioned in 2021. This paper, divided in two parts, aims to simulate the turbine mode fast start-up sequence made possible with the use of a FSFC and to assess the unit damage by means of 1D and 3D CFD simulations. The part I of this paper presents the 1D hydraulic transient simulation results of start-up sequences of unit U5 considering both conventional fixed speed technology and variable speed technology. The time evolution of the unit’s operating point is used as input data for 3D CFD simulations of part II, aiming to assess the impeller damage. Different control strategies to use the FSFC for turbine mode start-up sequence are analysed. Advantages and limits of each strategy are discussed, and recommendation is made for the Z’Mutt prototype demonstrator.

Details

Title
Turbine mode start-up simulation of a FSFC variable speed pump-turbine prototype – Part I: 1D simulation
Author
Alligné, S 1 ; Béguin, A 1 ; Biner, D 2 ; Münch-Alligné, C 3 ; Hasmatuchi, V 3 ; Hugo, N 4 ; Avellan, F 5 ; Dujic, D 6 ; C, Nicolet 1 

 Power Vision Engineering Sàrl, St-Sulpice, Switzerland 
 Institute of Systems Engineering, School of Engineering, HES-SO Valais-Wallis, Rawyl 47, Sion, Switzerland; Power Electronics Laboratory – PEL, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland 
 Institute of Systems Engineering, School of Engineering, HES-SO Valais-Wallis, Rawyl 47, Sion, Switzerland 
 Alpiq SA, Lausanne, Switzerland 
 Laboratory for Hydraulic Machines – LMH, Ecole Polytechnique Fédérale de Lausanne, Avenue de Cour 33 bis, 1007 Lausanne, Switzerland 
 Power Electronics Laboratory – PEL, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland 
Publication year
2021
Publication date
Jun 2021
Publisher
IOP Publishing
ISSN
17551307
e-ISSN
17551315
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2540836953
Copyright
© 2021. This work is published under http://creativecommons.org/licenses/by/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.