Publications de Daniel Biner | EPFL Graph Search

Numerical study on pressure fluctuations in a variable speed pump-turbine with head variations

Grid regulation capacities of Pumped Storage Hydropower Plants (PSHPs) are of great importance for today’s and future power supply systems. In this context, variable speed technologies provide solutions for enhanced operational flexibility of PSHP units. E ...

Institute of Physics2025

Experimental investigation of a FSFC variable speed pump-turbine prototype - Part2: runner fatigue reduction

Drazen Dujic, Daniel Biner

The demonstration of flexibility technologies to enhance ancillary services of Hydropower Plants (HPPs) is showcased by the XFLEX HYDRO H2020 European Project. The potential of Full Size Frequency Converters (FSFC) is numerically and experimentally assesse ...

Institute of Physics2024

Experimental investigation of a FSFC variable speed pump-turbine prototype - Part1: penstock fatigue reduction and fast active power regulation

Daniel Biner

The Z’Mutt pumping station is located in Canton Valais-Wallis, in Switzerland and is part of the Grande Dixence hydroelectric scheme. The unit 5 of this station has recently been upgraded with a 5 MW variable speed reversible Francis pump-turbine equipped ...

Institute of Physics2024

Fatigue investigations of a converter-fed variable speed pump-turbine for flexible power generation

Daniel Biner

Climate neutrality goals envisaged by many nations on the globe imply substantial deployment of intermittent renewable energy sources in the electrical power system that increases the need for grid stabilizing elements. One key asset to respond to these em ...

EPFL2024

Online Loss Calculation and Optimization of a M3C Driven Externally Excited SM

Cécile Münch-Alligné, Philippe Alexandre Bontemps, Drazen Dujic, Daniel Biner

2023

Discretization Uncertainties of Flow and Fatigue Damage Simulations of a Reversible Francis Pump-Turbine at Off-Design Operation in Turbine Mode

Philippe Alexandre Bontemps, Drazen Dujic, Daniel Biner

In the framework of the XFLEX HYDRO H2020 European Project, a 5 MW reversible Francis pump-turbine prototype, equipped with an industrial full size frequency converter, is investigated to demonstrate enhanced grid regulation capacities of variable speed hy ...

SPRINGER INTERNATIONAL PUBLISHING AG2022

CFD simulations of a Y-junction for the implementation of hydraulic short-circuit operating mode

François Avellan, Cécile Münch-Alligné, Daniel Biner

In the framework of the XFLEX HYDRO H2020 European Project, one of the demonstrators focuses on the implementation of the hydraulic short-circuit on the pump storage power plant of Grand-Maison owned by Electricite De France (EDF). The Grand-Maison power p ...

IOP PUBLISHING LTD2021

DuoTurbo: Implementation of a Counter-Rotating Hydroturbine for Energy Recovery in Drinking Water Networks

François Avellan, Samuel Chevailler, Cécile Münch-Alligné, Vlad Hasmatuchi, Daniel Biner

To enhance the sustainability of water supply systems, the development of new technologies for micro scale hydropower remains an active field of research. The present paper deals with the implementation of a new micro-hydroelectric system for drinking wate ...

2021

Crystal electric field excitations in the quantum spin liquid candidate NaErS2

Shang Gao, Daniel Biner, Christian Rüegg

The delafossite family of compounds with a triangular lattice of rare earth ions has been recently proposed as a candidate host for quantum spin liquid (QSL) states. To realize QSLs, the crystal electric field (CEF) ground state of the rare earth ions shou ...

AMER PHYSICAL SOC2020

Bound States and Field-Polarized Haldane Modes in a Quantum Spin Ladder

Bruce Normand, Pierre Bouillot, Daniel Biner, Christian Rüegg

The challenge of one-dimensional systems is to understand their physics beyond the level of known elementary excitations. By high-resolution neutron spectroscopy in a quantum spin-ladder material, we probe the leading multiparticle excitation by characteri ...

Amer Physical Soc2017

Comprehensive power loss modelling to improve the performance of an Energy Recovery Station for water utility networks

François Avellan, Cécile Münch-Alligné, Loïc Andolfatto, Daniel Biner

The work presented in this paper details the methodology applied to inventory and estimate the power losses in a micro-turbine with counter-rotating runners. The separation between the impact of design parameters and operational parameters on each identifi ...

Pennwell2017

Engineering & Performance of DuoTurbo: Microturbine with Counter-Rotating Runners

François Avellan, Vlad Hasmatuchi, Loïc Andolfatto, Daniel Biner

Considering the nuclear phase-out strategy of several European countries and the future tendency to promote renewable energies, the exploitation of small hydropower sites (

International Association For Hydraulic Research2016

Magnetic entropy landscape and Gruneisen parameter of a quantum spin ladder

Pierre Bouillot, Daniel Biner

We present measurements of the magnetic entropy landscape and Gruneisen parameter of the Cu2+ complex (C5H12N)(2)CuCl4 in a magnetic field. Our thermodynamic measurements are in very good agreement with a theoretical description by a S = 1/2 Heisenberg lad ...

American Physical Society2014

Field-controlled magnetic order in the quantum spin-ladder system (Hpip)2CuBr4

Thierry Giamarchi, Bruce Normand, Henrik Moodysson Rønnow, Pierre Bouillot, Joël Mesot, Daniel Biner, Christian Rüegg

Neutron diffraction is used to investigate the field-induced, antiferromagnetically ordered state in the two-leg spin-ladder material (Hpip)(2)CuBr4. This "classical" phase, a consequence of weak interladder coupling, is nevertheless highly unconventional: ...

2009

Direct Observation of Magnon Fractionalization in the Quantum Spin Ladder

Bruce Normand, Henrik Moodysson Rønnow, Joël Mesot, Jean-Sebastien Caux, Daniel Biner, Christian Rüegg

We measure by inelastic neutron scattering the spin excitation spectra as a function of applied magnetic field in the quantum spin-ladder material (C5H12N)(2)CuBr4. Discrete magnon modes at low fields in the quantum disordered phase and at high fields in t ...

2009

Thermodynamics of the Spin Luttinger Liquid in a Model Ladder Material

Bruce Normand, Pierre Bouillot, Daniel Biner

The phase diagram in temperature and magnetic field of the metal-organic, two-leg, spin-ladder compound (C5H12N)(2)CuBr4 is studied by measurements of the specific heat and the magnetocaloric effect. We demonstrate the presence of an extended spin Luttinge ...

2008