Publications related to Torque converter

Principle and Analysis of Radial-Force-Based Swirling Actuator for Low-Speed High-Torque Applications

This article proposes a swirling actuator that uses the electromagnetic radial force and mechanical gears to generate rotational torque. The proposed actuator generates a rotating radial force between an inner stator and a swirler. The gears on the swirler ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Optical rotating torque sensor with nano newton-meter resolution based on a hanging torsion wire

Simon Nessim Henein, Etienne Frédéric Gabriel Thalmann, Billy Nussbaumer

This article presents a novel torque measuring setup working in the nano newton-meter range. The central novelty is a long (1 meter range) thin (diameter of a few tens of micrometers) metallic wire used instead of the relatively stiff torsion zone of the s ...

euspen2021

Pushing the Limits of Efficiency and Power Density in High-Frequency Power Conversion Based on Wide-Band-Gap Technologies

Armin Jafari

The emergence of wide-band-gap (WBG) power transistors with low conduction losses and high-speed switching speeds has paved the way for more-than-ever efficient power electronics systems and huge energy saving potentials. Likewise, power density- the ratio ...

EPFL2021

97.4%-Efficient All-GaN Dual-Active-Bridge Converter with High Step-up High-Frequency Matrix Transformer

Elison de Nazareth Matioli, Armin Jafari, Palliyage Srilak Nirmana Perera, Mohammad Samizadeh Nikooytabalvandani

In this work, we demonstrate a state-of-the-art high step-up/down dual-active-bridge (DAB) converter designed with GaN transistors, to achieve a high efficiency and large power-density. A quasi-planar matrix transformer with high step-up/down ratio is demo ...

2020

Enhanced-performance integrated Resonant Switched-Capacitor and Buck DC-DC converters for application in extreme radiation and magnetic field environments

Giacomo Ripamonti

DC-DC converters based on Application Specific Integrated Circuits (ASICs) have been developed in this doctoral work for the High-Luminosity Large Hadron Collider (HL-LHC) experiments at CERN. They step down the voltage from a 2.5 V line and supply a load ...

EPFL2020

Automatically Starting and Secured Detent Escapement for a Timepiece

Simon Nessim Henein, Ilan Vardi

A horological detent escapement for a horological movement arranged to transmit a torque from said horological movement to an oscillating regulating organ of said horological movement, the regulating organ comprising a first mobile body and the escapement ...

2019

Development of a New Embedded Dynamometer for the Measurement of Forces and Torques at the Ski-Binding Interface

Alain Schorderet, Alain Michel Prenleloup, Frédéric Meyer

In alpine skiing, understanding the interaction between skiers and snow is of primary importance for both injury prevention as well as performance analysis. Risk of injuries is directly linked to constraints undergone by the skier. A force platform placed ...

2019

Unsteady Flow Numerical Simulations on Internal Energy Dissipation for a Low-Head Centrifugal Pump at Part-Load Operating Conditions

François Avellan, Xiaoran Zhao

Dredge pumps are usually operated at part-load conditions, in which the low-solidity centrifugal impeller could experience large internal energy dissipation, related to flow separation and vortices. In this study, SST k- and SAS-SST turbulence models were ...

2019

Predicting the dynamic behavior of Francis turbine generating units

Joao Gomes Pereira Junior

To reduce CO2 emissions and tackle global warming, an increasing amount of electrical power consumed around the world must be obtained from renewable sources. Among these sources, hydropower has not only the advantage of leaving a very small carbon footpri ...

EPFL2019

An Energy Efficient Power Converter for Zero Power Wearable Devices

Milad Ataei Ashtiani

Early diagnosis of Alzheimer's and epilepsy requires monitoring a subject's development of symptoms through electroencephalography (EEG) signals over long periods. Wearable devices enable convenient monitoring of biosignals, unlike complex and costly hospi ...

EPFL2018

Fluid-structure interaction mechanisms leading to dangerous power swings in Francis turbines at full load

François Avellan, Arthur Tristan Favrel, Christian Landry

Hydropower plants play an important regulatory role in the large scale integration of volatile renewable energy sources into the existing power grid. This duty however requires a continuous extension of their operating range, provoking the emergence of com ...

Elsevier2017

Analytical Models of Multiphase Isolated Medium-Frequency DC-DC Converters

Alfred Rufer, Asier Garcia Bediaga, Irma Villar, Alejandro Rujas

This paper presents new analytical equations, parametrized with respect to the number of converter phases, for multiphase isolated dc-dc topologies. This paper describes five multiphase isolated converter models, as well as their level of accuracy. Based o ...

Ieee-Inst Electrical Electronics Engineers Inc2017

Experimental Hydro-Mechanical Characterization of Full Load Pressure Surge in Francis Turbines

François Avellan, Arthur Tristan Favrel, Christian Landry, Andres Müller, Keita Yamamoto

Full load pressure surge limits the operating range of hydro-electric generating units by causing significant power output swings and by compromising the safety of the plant. It appears during the off-design operation of hydraulic machines, which is increa ...

2017

Energy Integration On Multi-Periods For Vehicle Thermal Powertrains

François Maréchal, Zlatina Kirilova Dimitrova

Internal combustion engines are the most applied energy converters in passenger cars. In order to increase their efficiency, energy integration techniques are used to recover waste heat. An adapted methodology is required to design the organic Rankine cycl ...

Wiley-Blackwell2017

Gas Turbine: Optimization of Energy Production and High Efficiency by Using Power Electronics

Alfred Rufer, Aziza Benaboud

The use of gas turbines in the power generation industry has been increasing. Their demand represents more than 50% of the world market of thermal power plants. Electric power generators using gas turbines as power sources are connected to the turbines thr ...

Elsevier Science Bv2016

Large Eddy Simulation of the Rotating Stall in a Pump-Turbine Operated in Pumping Mode at a Part-Load Condition

François Avellan, Olivier Pacot, Chisachi Kato

The investigation of the rotating stall phenomenon appearing in the HYDRODYNA pump-turbine reduced scale model is carried out by performing a large-scale large eddy simulation (LES) computation using a mesh featuring approximately 85 x 10(6) elements. The ...

American Society of Mechanical Engineers2016

Physical Mechanisms governing Self-Excited Pressure Oscillations in Francis Turbines

Andres Müller

The importance of renewable energy sources for the electrical power supply has grown rapidly in the past decades. Their often unpredictable nature however poses a threat to the stability of the existing electric grid. Hydroelectric powerplants play an impo ...

EPFL2014

Experimental study of the pressure fluctuations in a pump turbine at large partial flow conditions

Hongjuan Ran, Yao Zhang, Xin Wang

Frequent shifts of output and operating mode require a pump turbine with excellent stability. Current researches show that large partial flow conditions in pump mode experience positive-slope phenomena with a large head drop. The pressure fluctuation at th ...

Editorial Office Chinese Journal Mechanical Engineering2012

Hydrodynamics of a Pump-Turbine Operating at Off-Design Conditions in Generating Mode

Vlad Hasmatuchi

Modern pump-turbines are subject to frequent switching between the pumping and generating modes with extended operation under off-design conditions. Depending on the specific speed of the pump-turbine, the discharge-speed as well as torque-speed generating ...

EPFL2012

Fluid-Structure Coupling Effects on the Dynamic Response of Pump-Turbine Guide Vanes

Steven Roth

Hydraulic pump-turbines are subject to a high periodic excitation due to the Rotor-Stator Interaction, RSI. Basically, the RSI is caused by the impeller blade passage in the wake of the guide vanes in generating mode, or upstream from the guide vanes in pu ...

EPFL2012