Publications associées à Speed and Stability Limits for High-Speed Bearingless Disc Drives

Laser Doppler Vibrometer measurements of the 3D pressure field for the estimation of the radiation force produced by an acoustic standing-wave levitator

Acoustic levitation devices use powerful ultrasonic standing waves to levitate objects in mid-air. We have created a system and method to measure the full harmonic content of the acoustic field accurately. Our study revealed that levitated particles alter ...

Elsevier Science Sa2024

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

Principles and Test Result of Novel Full Passive Magnetic Levitation Motor with Diamagnetic Disk

Hannes Bleuler

This paper proposes a novel full passive magnetic levitation motor without active magnetic suspension. It has a magnetic levitation unit and a motor unit. The Halbach array permanent magnets and a pyrolytic graphite (PG) disk realize the full passive magne ...

IEEE2021

Characterization and Verification of Eddy-Current Position Sensing for Magnetic Levitation

Yves Perriard, Sean Thomas, Juan Patricio Tomás Peralta Fierro

Magnetically-levitated drives are compelling in applications where the long-lifetime operation or process chamber encapsulation is a requirement. To exploit these advantages, contactless position sensors are needed to estimate the position of the rotor. Of ...

2021

Controlling the rotation of drift tearing modes by biased electrode in ADITYA-U tokamak

Harshita Raj, Ankit Kumar, Abhijit Sen, Rohit Kumar, Sameer Kumar

The influence of background plasma poloidal rotation on the rotation frequency of the m/n = 2/1 drift tearing mode (DTM) has been studied in ADITYA-U tokamak. The poloidal rotation velocity of the background plasma in the ion diamagnetic direction is incre ...

2021

Experimental verification of X-point potential well formation in unfavorable magnetic field direction

Basil Duval, Holger Reimerdes, Christian Gabriel Theiler, Joaquim Loizu Cisquella, Marco Wischmeier, Mirko Wensing, Cedric Kar-Wai Tsui, Claudia Colandrea, Hugo De Oliveira, Sophie Danielle Angelica Gorno

Recent TCV experiments confirm the predicted formation of an electric potential well, below the magnetic X-point, in configurations with unfavorable

B_t

field direction (ion

\nabla B

drift away from the divertor), that substantially reshapes the typica ...

Elsevier2020

Design of Compact Bearingless Disc Drive Systems

Yves Perriard, Douglas Martins Araujo, Juan Patricio Tomás Peralta Fierro

Inflating costs and emerging applications are spawning interests toward smaller and faster electric drives. The challenges of miniaturization make magnetic bearings more appealing, as they provide intrinsic high-speed capability and need virtually zero-mai ...

2020

Transient Electronics for Smart Biodegradable Medical Implants

Matthieu Jean Michel Rüegg

Bioresorbable implantable medical devices show great potential for applications requiring medical care over well-defined periods of time. Such implants naturally degrade and resorb in the body, which eliminates adverse long-term effects or the need for a s ...

EPFL2020

Magnet-assisted ball drive

Pierre Dillenbourg, Francesco Mondada, Wafa Monia Benkaouar Johal, Séverin Lemaignan, Ayberk Özgür

The present invention concerns a magnet-assisted ball drive. The drive comprises a ball and a drive element in contact with the ball. The drive element is arranged to be rotated around its axis of rotation to drive the ball. The ball and the drive element ...

2019

Diamond Window Technology for Electron Cyclotron Heating and Current Drive: State of the Art

Konstantinos Avramidis

Nuclear fusion power plants require electron cyclotron (EC) heating and current drive (H&CD) systems for plasma heating and stabilization. High-power microwave beams between 1 and 2?MW generated by gyrotrons propagate in a dedicated waveguide transmission ...

TAYLOR & FRANCIS INC2019