Draft in progress:

Int’l Review of HL-LHC Magnet CircuitClose-out Report

Review Panel Members

Hans-Jörg Eckoldt (DESY), Jim Strait (FNAL), Neil Michell (ITER), Paolo Fessia (CERN), Steve Gourlay (LBNL), and Akira Yamamoto (KEK-CERN-Chair),

Link Person: Felix Rodriguez Mateos, Scientific Secretary: Samer Yammine

held at CERN on 9 – 10 Sept., 2019

Mandate and ObjectivesThe Panel is invited to:

1. Review the final layout (design) of the HL-LHC magnet circuits including the aspects related to poweringand quench protection strategies, making sure that the right choices have been made both in terms of circuit optimization and protection reliability;

2. Review the adequacy of the protection of the circuits for the different configurations that are adopted in order to assure safe commissioning and operation with beam. This aspect includes protection in case of quenches, failures of various components or of systems, effects of protection equipment to beam, protection of power converters, etc.;

3. Review the integration of equipment respecting installation & maintainability requirements;4. Review the proposed instrumentation for protection and the ancillary equipment (feeders, feedthroughs,

etc.) and its test in operational conditions in the IT String;

5. Assess on the Electrical Quality Assurance strategy of cold/warm equipment and circuits, making sure that insulation coordination is properly established.

While this is mainly a technically oriented review, (managerial aspects are reviewed by special Cost & Schedule Reviews) the Panel may comment on the level of integration and collaboration between various Work packages and teams participating to the circuits design and realization.

Agenda: 9 Sept. • Closed session• Lucio Rossi HiLumi Status and Charge to Review• Ezio Todesco Quick Overview on the HL-LHC (IR region) Magnets Characteristics• Felix R. Mateos Introduction to HL-LHC Circuits and Report from Prev. Review• Michele Martino Warm Powering and Adequacy with Respect to Requirements• --- Break ---• Amalia Ballarino Cold Powering• Ezio Todesco Superconducting Bus Bars Inside Cryostats• Arjan Verweij Quench Protection Strategies• ----- Lunch -----• Reiner Denz Quench Detection, related Hardware and Required Instrumentation• Dr David Carrillo1 Quench Protection Hardware• Lloyd Ralph Williams Design for the Protection and Diagnostic Feeders of the HL-LHC Triplets• Samer Yammine Contribution of Power Converters to the Protection of the Circuits• Daniel Wollmann Effects of Protection Equipment on the Beam and Reliability Studies

for the Circuit Protection Systems• --- Break ---• Michele Modena Integration Studies• Felix Rodriguez Mateos Voltage Withstand Levels• Closed session

Agenda: 10 Sept. • Frederic Savary 11T MBH: Electrical Integrity and Quench Protection Test Results• Giorgio Ambrosio et al. (IR) MQXF: Electrical Electrical Integrity and Quench Protection Test Results• Arnaud Pascal Foussat (IR) NbTi magnets: Electrical Integrity and Quench Protection Test Results• Coffee break• Samer Yammine Document Plan, Management of Change• Marta Bajko The HL-LHC Inner Triplet String• Thomas Otto Safety Aspects

• Closed session including working lunch for Panel

• Marta Bajko Risk analysis of the string systems• Emmanuele Ravaioli Table with voltages and temperatures on QXF magnets• Frederic Savary et al. Voltage withstand levels and quench heater position for QXF and 11T MBH• Herve Prin Splices in HL-LHC cryostats• Andrea Apollonio Reliability of the complete inner triplet circuit protection• Daniel Wollmann Feedback from LHC and MDs done with respect to effects to beam by misfiring of

protection elements

• 17:15 Close out of the Review

Executive Summary (1/2)• The 2nd International Review of HL-LHC Magnet Circuit was held on

9-10 September, 2019, and the review panel received 21+7 reports.

• The panel has been very much impressed with the design and development much integrated and matured, since the 1st review in 2016, and support the general design and the plan for the construction.

• 11T dipole and MQXF circuit layout, quench protection schemes, UQPDS, etc.,

Executive Summary (2/2)• The panel understood that QPHT configurations have been settled differently

with external QPHTs for 11 T, and impregnated QPHT for MQXF, because of different technical boundary conditions such as maximum voltage and project status. • Any change of MQXF QPHT configuration shall be well justified.

• The panel agrees that the integrated system test at SM18 is a critical milestone of the project and it will provide the only possibility to verify many circuit aspects, not tested and testable before on single magnet. • The panel believes that it will save much time to reach the HL-LHC

completion. It is an important part of the project risk reduction, which allows the possibility to identify issues not foreseen by individual magnet tests or the system analysis. It will also provide important benefits for testing safety, operation and procedures

Individual Mandate and Response

Working in progress

Appendix • Executive summaries of from Previous Review Reports.

• Intʼl review in 2016• Internal review in 2017

Appendix 1: Executive Summary of Review Panel Report of Int’l Review 2016

Appendix 1: Summary of Review Panel Report of Int’l Review 2016

Appendix 2: Review Panel Report of Internal Review 2017

Appendix 2: Review Panel Report of Internal Review 2017