2. 09/05/2016 2 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project 2 nd Workshop of the Spanish Traineeship Programme FTEC 2015 Alejandro Fernandez Navarro Supervisor: Arjan Verweij TE-MPE-PE 09.05.2016 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez

3. 09/05/2016 3 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Outline Introduction Overview CLIQ-QPS design for D1 and D2 connected in series CLIQ-QPS design for D1 and D2, independent circuits (or decoupled) FMEA (Failure Modes and Effects Analysis) Failure scenario study for the QH-QPS of the 11 T chain Actions planned in the short-term Annex

4. 09/05/2016 4 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Introduction CLIQ (Coupling-Loss Induced Quench) Current change Magnetic field change Coupling losses (heat) Temperature rise Quench 1 st generation of CLIQ units manufactured at CERN (2015) First test of the CLIQ system on a spare LHC dipole magnet (SM18, August 2015) Test campaign report written: https://edms.cern.ch/document/1606724/ 0.1/TAB3

5. 09/05/2016 5 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Overview CLIQ-based Quench Protection System (QPS) design for D1 and D2 of HL-LHC Risk analysis of a redundant CLIQ-QPS for D1 (FMEA methodology) Failure scenario study for the Quench Heater (QH) protection of the 11 T chain of HL-LHC (using TALES for the electro- thermal dynamic simulations) 11 T collimator 11 T Separation Dipole Recombination Dipole

6. 2 x 750 V / 40 mF 3 x 500 V / 40 mF 4 x 500 V / 40 mF 09/05/2016 6 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez CLIQ-QPS design for D1 and D2 Connected in series Nominal performance Failure: CLIQ 4 not fired

7. 09/05/2016 7 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez CLIQ-QPS design for D1 and D2 Independent circuits (or decoupled) D1 D2 = ? Total decoupling confirmed in simulations 1 x 700 V / 40 mF per magnet

8. 09/05/2016 8 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez CLIQ-QPS design for D1 and D2 Independent circuits (or decoupled) D1 D2 2 x 600 V / 40 mF per magnet (redundant) D1 discharge in nominal performance

9. 09/05/2016 9 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez FMEA (Failure Modes and Effects Analysis) To identify reliability problems in a CLIQ system and to assess the appropriate level of redundancy of the internal CLIQ components. Goal: Risk Priority Number: RPN = Severity * Probability * Detectability Failure scenarios Triggering delay of 1 ms of one CLIQ unit Spurious triggering of one CLIQ unit One CLIQ unit not firing Short-circuit of the capacitor bank of one CLIQ unit Non-nominal discharge due to one/several capacitors in open/short circuit (depending on the capacitor bank configuration)

10. 09/05/2016 10 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Trigger card Redundant circuit (?) Capacitors power supply Capacitor bank (1,2 parallel/series,4?) Bi-directional thyristor Redundant thyristor (?) Pulse transformer Redundant transformer (?) TC power supply (Redundant power supply?) Circuit schematic of a CLIQ unit

11. 09/05/2016 11 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Failure rates for the components of CLIQ

12. 09/05/2016 12 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez FMEA study

13. 09/05/2016 13 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Failure scenario study for the QH-QPS of the 11 T chain ROXIE (Susana Izquierdo) TALES Comparison between ROXIE and TALES simulations for one 11 T magnet without quench back Failure case: QHs of the 1 st pole, 1 st aperture not fired Goal: Support Susana’s QH-QPS design of the 11 T. TALES can provide simulations of chain of magnets and simulate the quench back effect Very good agreement between TALES and ROXIE Satisfactory results: peak voltage-to-ground decreased in a factor ~0.6 with the QB effect voltages increased by 10-20 % in the 11 T chain compared to 1 magnet

14. 09/05/2016 14 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Actions planned in the short-term Improve the FMEA study by analysing the reliability data with the commercial software Isograph Reliability Workbench To apply the FMEA methodology to the QH protection system of the MQM magnets of the LHC To finish the design of the proposal of a hybrid CLIQ-QH protection system for the 11T magnet To be the user of new physical modules and tester of evolving features of the new electro-thermal-mechanical simulating framework STEAM (under development). SCRUM methodology for project management

15. 09/05/2016 15 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Thank you for your attention!

16. 09/05/2016 16 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Annex

17. Output results - Figures - GIF animations - Data files 17 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez Modelling, simulating, testing Modelling Input - Geometric design - Cable data - Material properties Simulating Input - Excel file: Electrical circuit, geometry, magnetic field map, cable and material properties Testing and model validation ROXIE simulations (magnetic field calculations) Output - Magnetic field map MATLAB post- processing TALES Matlab application for electro- thermal dynamic simulations Analysis of results SM18 (Magnet Test Facility of CERN) PredictionsMeasurements Comparison and model validation 09/05/2016

18. 18 Modelling and testing of circuit protection of new superconducting magnets for the HL-LHC project A. Fernandez D1 and D2 characteristics