Publications associées à Cascade hyposynchrone

Study of flexible operating conditions in variable-speed hydraulic turbines : advanced models and experimental validation

The global imperative to transition from fossil fuel-based energy sources to renewable alternatives has become increasingly urgent in the pursuit of sustainable and renewable power generation. This paradigm shift necessitates innovative approaches to manag ...

EPFL2024

Rock-Flow Cell Parameters Evaluation Using Ultrasound Doppler Velocimetry

Giovanni De Cesare, Javier Neves da Silva, Andre Luis Stakowian

This work presents a study of two-phase flow generated inside a rock-flow cell setup. It is characterized by a pipe section filled with fluid (oil in our studies) that is put into oscillation around its mass centre by an electric motor. This type of appara ...

2023

Increasing the Energy Efficiency of Gas Boosters for Hydrogen Storage and for Refueling Stations

Alfred Rufer

A new electrically driven gas booster is described as an alternative to the classical air-driven gas boosters known for their poor energetic efficiency. These boosters are used in small scale Hydrogen storage facilities and in refueling stations for Hydrog ...

MDPI2023

Torque Computation With the Isogeometric Mortar Method for the Simulation of Electric Machines

Rafael Vazquez Hernandez, Bernard Kapidani

In this work, isogeometric mortaring is used for the simulation of a six-pole permanent magnet synchronous machine. Isogeometric mortaring is especially well suited for the efficient computation of rotating electric machines, as it allows for an exact geom ...

Institute of Electrical and Electronics Engineers2022

Modelling and Sensors for Magnetically-Levitated Disc Drives

Juan Patricio Tomás Peralta Fierro

The development of new industrial applications has diverted the focus of research towards compacter and faster rotatory drives. These requirements push the classical ball-bearings of electric motors to the limits in terms of operational lifetime and fricti ...

EPFL2022

Ferroelectric Effects Probed by in situ Transmission Electron Microscopy

Reinis Ignatans

Ferroelectric perovskite oxides are widely used in sensors, actuators and optical modulators and, at the same time, they show promise for implementation in future applications such as energy storage, memory and cooling devices. At the infancy of the discov ...

EPFL2022

Long Spin Lifetime in Rare-Earth Single-Atom Magnets at Surfaces

Boris Sorokin

Further miniaturisation of magnetic storage devices requires an advent of new types of magnets, since classical ferromagnetic materials show lack of remanence at nano- and subnanoscale. A single atom can represent the smallest possible bit of information. ...

EPFL2022

Efficiency Optimisation of Slotless Magnetic Bearing Machines

Yves Perriard, Douglas Martins Araujo, Leopoldo Rossini, Guzmán Borque Gallego

Efficiency is one of the key performance indexes in the design of electric motors. When considering fully active magnetic bearing machines, this aspect gain further relevance due to the necessity of actively controlling all the remaining degrees of freedom ...

2021

Breakerless Protection for Voltage Source Converter-Based Marine DC Power Supply Systems

Drazen Dujic, Seongil Kim

DC power supply systems utilising voltage source converters offer several advantages compared with their counterparts in marine low-voltage DC power distribution networks. In case of a two-level voltage source converter fed by a synchronous generator which ...

IEEE2021

Low-energy stereodynamics of ion-forming reactions

Junwen Zou

In this thesis, an experimental study of low-temperature stereodynamics in the reactive scattering of Ne(3P2) + X collisions (X = Ar, Kr, Xe, CO and N2) is presented. The steric effect of Ne(3P2) in these reactions is observed experimentally using a contro ...

EPFL2021

Effect of electrode composition and patterning method on the lifetime of silicone-based dielectric elastomer actuators (DEA) under different environmental conditions

Herbert Shea, Fabio Beco Albuquerque

We report an experimental investigation of the lifetime of dielectric elastomer actuators (DEAs) under constant DC actuation, with a characterization setup which allows the monitoring of strain and resistance over time for 6 DEAs in parallel. We show how t ...

SPIE-INT SOC OPTICAL ENGINEERING2021

Data-Driven LPV Controller Design for Islanded Microgrids

Alireza Karimi, Seyed Sohail Madani

This paper presents a data-driven multivariable Linear Parameter Varying (LPV) controller design method. The synthesis process is based on frequency-domain data corresponding to different operating points of the plant. The performance and also stability co ...

ELSEVIER2021

Performance assessment of grid-forming and grid-following converter-interfaced battery energy storage systems on frequency regulation in low-inertia power grids

Mario Paolone, Fabrizio Sossan, Yihui Zuo, Sidi-Rachid Cherkaoui, Antonio Zecchino, Zhao Yuan

Power systems with large shares of converter-interfaced renewables may be characterised by low grid inertia due to the lack of frequency containment provided by synchronous generators. Battery energy storage systems (BESSs), which can adjust their power ou ...

2021

Partial Discharge Localization Using Time Reversal: Application to Power Transformers

Farhad Rachidi-Haeri, Marcos Rubinstein, Mohammad Azadifar, Amirhossein Mostajabi, Hamidreza Karami

In this work, we present a novel technique to locate partial discharge (PD) sources based on the concept of time reversal. The localization of the PD sources is of interest for numerous applications, including the monitoring of power transformers, Gas Insu ...

2020

Design and development of the efficient anguilliform swimming robot- MAR

Auke Ijspeert, Peter Eckert, Anouk Looijestijn

Propulsion of swimming robots at the surface and underwater is largely dominated by rotary propellers due to high thrust, but at the cost of low efficiency. Due to their inherently high speed turning motion, sharp propeller blades and generated noise, they ...

2020

Protection Coordination in Marine DC Power Distribution Networks

Seongil Kim

The increasing penetration of renewable energy sources, energy storage systems (ESSs), and DC loads has opened the door to DC technology to pave its way into future grids. The shift has been more obvious in the marine domain supported by track records of i ...

EPFL2020

Deexcitation Characterization for Power Supply Protection in DC Shipboard Power Systems

Drazen Dujic, Seongil Kim

The deexcitation of a synchronous machine has been used for the protection of the power supply based on a diode rectifier in marine dc power distribution networks. The fault current from the generator can be eliminated with the protection method utilizing ...

IEEE2020

Data-Driven Distributed Reactive Power Sharing in Microgrids

Alireza Karimi, Seyed Sohail Madani

In this paper, reactive power sharing for Photovoltaic (PV) units in islanded microgrids has been formulated as a robust control design problem and is solved using convex optimization method. In addition to reactive power sharing, the disturbance rejection ...

IEEE2020

Topology Optimization for Coils of Electric Machine with Level-set Method

Yves Perriard, Adrien Jean-Michel Thabuis, Xiaotao Ren

This work studies the level-set based topology optimization for the optimal layout of winding in electric motor. The functional to optimize is to maximize the torque in the air-gap. The coil domain is initiated by a level set function. The time evolutionar ...

IEEE2019

A low-cost, autonomous mobile platform for limnological investigations, supported by high-resolution mesoscale airborne imagery

David Andrew Barry, Ulrich Lemmin, Htet Kyi Wynn, Anton Ivanov, Beat Marcel Geissmann, Abolfazl Irani Rahaghi, Stepan Tulyakov, Philippe Olivier Paccaud, Ludovic Zulliger, Nawaaz Sidharth Gujja Shaik, Jean-Luc Liardon, Jérôme Béguin, Pascal Klaus

Two complementary measurement systems – built upon an autonomous floating craft and a tethered balloon – for lake research and monitoring are presented. The autonomous vehicle was assembled on a catamaran for stability, and is capable of handling a variety ...

2019