High Temperature Superconductors in the LHC
Maquette of High Temperature Superconducting Link of the type needed at LHC Point 7. Image credits: CERN
Superconducting links in accelerator systems enable powering of the cryo-magnets from remote power converters. The development carried out within Task 5 of the EuCARD Work Package7 aims at providing such technology for the remote powering of LHC magnets.
The use of High Temperature Superconductors (HTS) in Superconducting Links has the great benefit of enabling the development of a powering system where superconductors can be operated with a generous temperature margin. To enable the use of superconductors with tape geometry, a novel concept of cable optimized for DC electrical transmission (Twisted-Pair Cable) has been developed and demonstrated [1], [2]. A cabling machine enabling the controlled assembly of km-long Twisted Pair cables - made from superconductors with different mechanical characteristics - has been conceived, assembled and commissioned at CERN. A full-scale 5 m long prototype link has been made at CERN and successfully tested in nominal conditions at the University of Southampton [3]. A 20 m-long full scale link is being assembled at CERN, where it will be tested in nominal and transient conditions.
The main outcomes of this activity are: (1) the development of a novel concept of superconducting cable for electrical transmission that can be made from any of the HTS tape-conductors today available (BSCCO 2223, YBCO or MgB2); (2) the development of a new cabling machine for the controlled assembly of the cable; (3) the development of a full superconducting link system that could be used at LHC Point 7 for the powering of the superconducting magnets. The developed technology could be applied for feeding any superconducting system requiring currents in the 1 kA range at any temperature from liquid nitrogen to liquid helium.
