Publications by François Roy | EPFL Graph Search

Evaluation of the Applicability of Phenomenological HTS Models for Numerical Analysis of Quenches in Coated Conductors: Simulations vs. Experiments

François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

The electrical resistivity of coated conductors is strongly related to the inter-dependent set of parameters (J, H, T), respectively current density, magnetic field and temperature. On the one hand, it is difficult to isolate the contribution of each of th ...

IEEE Institute of Electrical and Electronics Engineers2011

Modeling and Characterization of Coated Conductors Applied to the Design of Superconducting Fault Current Limiters

François Roy

The Superconducting Fault Current Limiter (SFCL) appears to be a device of great interest to efficiently build the electrical grid of tomorrow. With the recent progress made by the superconducting wires manufacturers, there are needs coming from the indust ...

EPFL2010

Numerical studies of the quench propagation in coated conductors for Fault Current Limiters

François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

A fundamental understanding of the quench phenomenon is crucial in the future design and operation of HTS based Fault Current Limiters (FCLs). The key parameter that quantifies the quenching process in superconductors is the normal zone propagation (NZP) v ...

IEEE Institute of Electrical and Electronics Engineers2009

Assessment of the Computational Performances of the Semi-Analytical Method (SAM) for Computing 2-D Current distributions in Superconductors

François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

The semi-analytical method (SAM) is a fast integral technique for solving small 2-D, time-transient electromagnetic problems in high temperature superconductors (HTS) with transport current and/or applied field. The method in itself is a generalization of ...

IEEE Institute of Electrical and Electronics Engineers2009

Quench propagation in coated conductors for fault current limiters

François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

A fundamental understanding of the quench phenomenon is crucial in the future design and operation of high temperature superconductors based fault current limiters. The key parameter that quantifies the quenching process in superconductors is the normal zo ...

Elsevier2009

Comparison Between the Behavior of HTS Thin Film Grown on Sapphire and Coated Conductors for Fault Current Limiter Applications

François Roy, Bertrand Dutoit, Bertrand Dutoit

The major drawback for the commercialization of fault current limiter (FCL) made of YBCO on sapphire is their expensive price. In the recent years, coated conductors (CC) have been extensively developed and, due to their lower prices, have been recently te ...

IEEE Institute of Electrical and Electronics Engineers2009

Magneto-thermal finite element modeling of 2nd generation HTS for FCL design purposes

Francesco Grilli, François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

Coated conductors are very promising for the design of novel and e±cient Fault Current Limiter (FCL). However, before considering using them in a power grid, their thermal and electromagnetic behaviors in the presence of over-critical currents need to be i ...

Iop Publishing Ltd, Dirac House, Temple Back, Bristol Bs1 6Be, England2008

Magneto-Thermal Modeling of Second-Generation HTS for Resistive Fault Current Limiter Design Purposes

Francesco Grilli, François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

Coated conductors are very promising for the design of novel and efficient resistive Fault Current Limiters (FCLs). However, a detailed knowledge about their thermal and electromagnetic behaviors in the presence of over- critical currents is crucial for th ...

IEEE Institute of Electrical and Electronics Engineers2008

Evaluation of two commercial finite element packages for calculating AC losses in 2-D high temperature superconducting strips

Francesco Grilli, François Roy, Frédéric Sirois, Bertrand Dutoit, Bertrand Dutoit

This paper compares the speed and accuracy of two commercial packages based on the finite element method (FEM) for calculating the AC losses in high temperature superconductors (HTS). The softwares investigated in this paper were COMSOL Multiphysics and FL ...

2008