1. A. BallarinoEucard MeetingCERN,20/03/2013 High-Tc Superconducting Links for the LHC WP 7 – Task 5 A.Ballarino, TE-MSC, CERN Task 5 participants : A. Ballarino, B. Bordini, J. Fleiter, A. Gharib, G. Hurte (CERN) V. Cubeda, G. Grasso, M. Tropeano (Columbus) C. Beduz, Y. Yang (University of Southampton) A. Aubele, A. Hallbauer (Bruker HTS) CERN, 20-03-2013

2. A. BallarinoEucard MeetingCERN,20/03/2013 Disclaimer: The presentation strictly follows instructions received from WP leader  Aim of the Task  Main achievements  Status of deliverables  Post-Eucard era Outline

3. A. BallarinoEucard MeetingCERN,20/03/2013 Aim of the Task and Deliverable Objective: demonstrate possibility of providing remote powering of LHC magnets fed from LHC P7 using HTS SC-links. Initial concern: potential higher heat load on existing Nb-Ti SC-links. Present concern: need to remove power converters from the tunnel radiation environment. Configuration of SC-Link at LHC P7 could be applied also at LHC P3 Deliverable: Design and assembly of a superconducting link, 20 m long, containing 24 pairs of 600 A HTS cables. The test of the link is not included in the Task

4. A. BallarinoEucard MeetingCERN,20/03/2013 HTS Link for the LHC Machine – P7 Current Leads and Power Converters ~ 250 m P3 would require the same type of link 48 cables rated at 600 A per link Two links each about 500 m long

5. A. BallarinoEucard MeetingCERN,20/03/2013 Layout of the link in the LHC tunnel Preliminary integration studies, Y. Muttoni

6. A. BallarinoEucard MeetingCERN,20/03/2013 Main achievements 1.Development of a novel type of cable (twisted-pair cable) made from tape conductor and optimized for DC electrical transmission. Iop  1 kA Conductors: MgB 2, YBCO and BSCCO 2223. Cable geometry and cabling process accommodate for the different mechanical properties of the three conductors 2Validation of 2 m long cables at 4.2 K (Fresca). Iop up 2  4.2 kA @ 4.2 K and in self-field 3Preparation of short (up-to 5m) multi-cable assembly (2  24 cables) as required for integration in the SC-Link for LHC P7

7. A. BallarinoEucard MeetingCERN,20/03/2013 + 600 A - 600 A  5.6 mm  = 40 Twisted-pair cable (Iop  1000 A)

8. A. BallarinoEucard MeetingCERN,20/03/2013 Main achievements 4.Construction at Southampton University of a test station enabling the operation of 5 m SC-link and of the associated current lead cryostat. Coolant:He gas at variable temperatures. Design and assembly at CERN of 5 m long complete (2  24 MgB 2 cables) SC link (48 cables in Nexans semi-flexible cryostat) integrated in the test station in Southampton and successfully tested in nominal operating conditions 5.Design and assembly at CERN of a test station enabling the measurement of 20 m long cables and SC-links in a variable temperature range (5 K-70 K, I up to 20 kA). Commissioning of the test station in Dec. 2013. Successful test of 20 m long twisted-pair YBCO cable pair assembly 6.Design and construction at CERN of two cabling machines enabling the controlled assembly of the twisted-pair cables: stacking + electrical insulation, twisting + electrical insulation

9. A. BallarinoEucard MeetingCERN,20/03/2013 CERN SC-Link Test Station

10. A. BallarinoEucard MeetingCERN,20/03/2013 Main achievements 7.Quench tests performed on a full-scale 5 m long SC-Link at Southampton University. Verification of radial heat transfer – quench of one cable should not provoke a resistive transition in the other cables contained in the same SC-Link cryostat (different electrical circuits). Test confirming “sufficient” thermal insulation. Analysis and modelling on- going 8.Cabling of 100 m of stacked, insulated and twisted conductor being launched at CERN – using the newly developed cabling machines 8.Agreed deliverable – 20 m long superconducting link assembly – planned to be available by end of April 2013 – MgB 2 tape conductor provided by Columbus in the framework of the Eucard collaboration

11. A. BallarinoEucard MeetingCERN,20/03/2013  Test at CERN of the Eucard deliverable (20 m long link)  Parallel development in collaboration with Columbus Superconductors of MgB 2 round wires for application to high-current cables (up to 20 kA)  Design assembly and test of 60 m a long SC-link system as required for integration in the LHC machine at Point 7  Development and test of high-current cables, multi-cable assemblies (Itot > 150 kA) and SC-links for application at LHC P1 and P5 (vertical transfer along  80 m)  SC-Links transferring the current from the surface to the LHC tunnel for the LHC Hi-Luminosity upgrade Post Eucard-era

12. A. BallarinoEucard MeetingCERN,20/03/2013 Thanks for your attention !