Publications associées à Applicability of Non-Destructive Examination to Iter TF Joints Nb3Sn

A Spectral Ansatz for The Long-Time Homogenization of The Wave Equation

Consider the wave equation with heterogeneous coefficients in the homogenization regime. At large times, the wave interacts in a nontrivial way with the heterogeneities, giving rise to effective dispersive effects. The main achievement of the present wor ...

Ecole Polytechnique2024

DC Power Distribution Networks with Direct Current Transformers

The shift towards DC power distribution networks, enabled by power electronics technologies, is changing the nature of electrical power systems. Nowadays, DC power distribution networks can effectively support the high penetration of distributed energy res ...

EPFL2024

Direct observations of X-rays produced by upward positive lightning

Farhad Rachidi-Haeri, Marcos Rubinstein, Antonio Sunjerga, Thomas Chaumont

X-rays have been observed in natural downward cloud-to-ground lightning for over 20 years and in rocket-triggered lightning for slightly less. In both cases, this energetic radiation has been detected during the stepped and dart leader phases of downward n ...

Nature Publishing Group2024

Power Aware Placement of On-Chip Voltage Regulators

Rassul Bairamkulov

In traditional power delivery networks, the on-chip supply voltage is provided by board-level converters. Due to the significant distance between the converter and the load, variations in the load current are not effectively managed, producing a significan ...

Ieee-Inst Electrical Electronics Engineers Inc2024

The time-domain Cartesian multipole expansion of electromagnetic fields

Farhad Rachidi-Haeri, Marcos Rubinstein, Nicolas Mora Parra, Elias Per Joachim Le Boudec, Emanuela Radici, Chaouki Kasmi

Time-domain solutions of Maxwell’s equations in homogeneous and isotropic media are paramount to studying transient or broadband phenomena. However, analytical solutions are generally unavailable for practical applications, while numerical solutions are co ...

Nature Publishing Group2024

Polarization-enhanced GaN Schottky barrier diodes: Ultra-thin InGaN for high breakdown voltage and low Ron

Elison de Nazareth Matioli, Alessandro Floriduz, Zheng Hao

In this work, we present a concept that leverages the strong piezoelectric polarization field in InGaN, which counteracts the external electric field at reverse bias. We show that despite the smaller InGaN band-gap and lower critical electric field, its st ...

2024

DEMO toroidal field coil fast discharge unit integration studies

Roberto Guarino, Alberto Ferro

The Fast Discharge Units (FDUs) of the Superconducting (SC) Toroidal Field (TF) coils in the European demonstration fusion power plant DEMO warrant the machine integrity over its full lifetime against severe failure events, such as SC coil quenches or any ...

Elsevier Science Sa2024

Performance Comparison of Cables With Partial Transposition

Pierluigi Bruzzone, Kamil Sedlák, Chiara Frittitta, Federica Demattè

The need of full transposition of the current carrying elements (strands) in large cables is frequently retained as top design criterion for conductors operating in pulsed mode. However, when the transposition error, i.e., the inductance difference among t ...

IEEE Institute of Electrical and Electronics Engineers2024

Re-design of EU DEMO with a low aspect ratio

Hartmut Zohm

The design point that had been chosen for EU DEMO in 2016 is reviewed here and a modification is proposed with a lower aspect ratio. Previously the same aspect ratio, A, was chosen for EU DEMO as in major tokamak experiments including ITER (A = 3.1), and, ...

2024

Static and Dynamic Voltage Balancing for an IGCT-Based Resonant DC Transformer

Drazen Dujic, Nikolina Djekanovic, Renan Pillon Barcelos

This paper focuses on the operational characteristics of a medium voltage resonant DC transformer based on a split capacitor IGCT 3L-NPC leg. The study delves into both the dynamic and static balancing aspects of the 3L-NPC when operating in a two-level, 5 ...

2024

Ripple Voltage and Loss Reduction of Single-Phase ISOP SST by Eliminating the Second Harmonic Current in LLC Converters

Drazen Dujic, Tianyu Wei, Andrea Cervone

In two-stage solid-state transformers with input-series output-parallel structure, the LLC converter operating at a fixed switching frequency is a common choice for the isolated DC/DC conversion stage because it can provide a high efficiency and a fixed vo ...

2024

Gyrokinetic simulations of turbulence in magnetic fusion plasmas using a delta-f PIC scheme with evolving background

Moahan Murugappan

Using the GKEngine code which simulates an electrostatic plasma with adiabatic electron response under a sheared-slab geometry, an attempt at developing a hybrid approach between the delta-f and full-f schemes to describe plasma profiles exhibiting high fl ...

EPFL2024

Benign termination of runaway electron beams on ASDEX Upgrade and TCV

Basil Duval, Stefano Coda, Joan Decker, Umar Sheikh, Jean Arthur Cazabonne, Claudia Colandrea, Luke Simons, Gergely Papp, Bernhard Sieglin

This paper discusses the development of a benign termination scenario for runaway electron (RE) beams on ASDEX Upgrade and TCV. A systematic study revealed that a low electron density (n e) companion plasma was required to achieve a large MHD instability, ...

Iop Publishing Ltd2024

Phase Shift Angle Segmentation Modulation for Soft-Switching Medium-Voltage DAB Converter With Series-Connected SiC MOSFETs

Heng Fang, Rui Lu, Chengmin Li

The medium-voltage (MV) dual active bridge (DAB) converter with series-connected SiC (S-SiC) MOSFETs is a promising solution for high-power-density isolated dc/dc converter. To improve the voltage sharing and reliability of S-SiC, relatively large snubber ...

Ieee-Inst Electrical Electronics Engineers Inc2024

Modeling and optimization of PCB coils for inductive power transfer systems

Xiaotong Du

The auxiliary power supply for medium voltage converters requires high insulation capability between the source and the load. Inductive power transfer technology, with an air gap between the primary and secondary coil, offers such high insulation capabilit ...

EPFL2024

Active Voltage Balancing with Seamless Integration into Dual Gate Driver for Series Connection of SiC MOSFETs

Drazen Dujic

The versatility of half-bridge configuration of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET) power module contributes to its widespread adoption, highlighting the popularity and significance of its corresponding dual gat ...

2024

A Dual-Channel Gate Driver Design with Active Voltage Balancing Circuit for Series Connection of SiC MOSFETs

Drazen Dujic

Dual-channel gate driver is commonly utilized in the industry for accommodating the widespread use of half-bridge power modules. As wide-bandgap devices become increasingly prevalent due to their superior switching characteristics compared with conventiona ...

2024

Photoinduced Second-Order Nonlinearities in Centrosymmetric Media

Ozan Yakar

The interaction of light and matter enables nonlinear frequency conversion and the creation of coherent currents. The optical control of electric currents is of fundamental relevance and prominent research focus in the last decades. These photocurrents ena ...

EPFL2024

On Energy Control of Modular Multilevel Converters

Milan Utvic

Owing to the advancements in the area of power electronics, efficient and flexible ac to dc conversion is made possible, bringing back into focus the idea of the dc power transmission at various voltage levels. Several technical and economical factors advo ...

EPFL2023

Experimental study of stability, quench propagation and detection methods on 15 kA sub-scale HTS fusion conductors in SULTAN

Pierluigi Bruzzone, Kamil Sedlák, Nikolay Bykovskiy, Ortensia Dicuonzo

High-temperature superconductors (HTSs) enable exclusive operating conditions for fusion magnets, boosting their performance up to 20 T generated magnetic fields in the temperature range from 4 K to 20 K. One of the main technological issues of HTS conduct ...

2023