Sep 25, 2018
20,8 T for the high-field magnet NOUGAT
20,8 T for the high-field magnet NOUGAT

NOUGAT HTS-MI insert picture

The DACM is involved in several high-field magnet projects, particularly for medical applications (MRI / NMR) and large test stations (LNCMI hybrid magnet).
In order to generate high field, it is necessary to use new generation High Temperature Superconductors (HTS) instead of NbTi or Nb3Sn LTS.
The HTS R & D studies the means of making such magnets and investigates the problems inherent in these conductors with these intense field values (G. Dilasser's thesis on the currents of screens [1], M. ALHarake's thesis on mechanics [2], Internal R & D for uninsulated windings ...).






[1] Etude expérimentale et numérique des courants d’écrantage dans les aimants supraconducteurs à haute température critique REBCO, thèse soutenue en 2017, G. Dilasser
[2] Contribution à l’étude d’un aimant haut-champ 30-40 T, thèse en cours, M. ALHArake

As part of this R & D, the NOUGAT high temperature superconducting insert has been studied, realized and tested; it operated up to 20.8 T for 45 minutes. It generated 12.8 T in a 8 T background field provided by ‘bitters’ resistor coils at LNCMI Grenoble (dark blue dot in Figure 2).
This insert is composed of 9 double-pancakes (Figure 1) with an internal diameter of 50 mm using the 'Metal-as-Insulation' (MI) winding  to replace the traditional insulation by a metallic co-winding; it is thus possible to eliminate the complex protection system because the winding reacts autonomously to a quench thanks to the bypassing of the resistive zone by the current.
This is a decisive first step towards its point of operation at 30 T (10 T generated by the insert in 20 T outsert, red dot in Figure 2); the final tests will be carried out up to this value in spring 2019 when the LNCMI Grenoble test station is  available.
This insert was made in DACM thanks to ANR funding with 2 partners, CNRS-LNCMI and CRETA.



Last update : 09/27 2018 (4488)


Retour en haut