Thermodynamic optimisation of 70kA binary current lead - Final report
In the frame of the European Fusion Technology Programme, the Forschungszentrum Karlsruhe and the Centre de Recherches en Physique des Plasmas are developing a 70 kA current lead for the toroidal field coil system of the International Thermonuclear Experimental Reactor ITER-FEAT using high-temperature superconductors (HTS). The thermal behaviour of binary 70 kA HTS current leads has been simulated numerically. The optimum temperature of the helium and the conductor at the cold end of the heat exchanger has been found to depend on the assumed refrigerator efficiency, the engineering critical current density of the silver/gold/bismuth-2223 tapes at the envisaged temperature at the warm end of the superconductor and the cross-section of the stainless steel support. Reduced operating current densities and a lower warm end temperature provide an enhanced temperature margin. A larger stainless steel cross-section increases the heat capacity of the HTS part of the current lead. Both measures would considerably prolong the time available to discharge the toroidal field coils in the case of loss of flow.
Bibliographic Reference: An internal report LRP 720/02, February 2002, pp.32
Availability: Available free of charge from: École Polytechnique Fédérale de Lausanne (EPFL), Ecublens, CH-1015 Lausanne Fax +41-21-6934747
Record Number: 200214710 / Last updated on: 2002-05-10
Original language: en
Available languages: en