Commissioning of the LHC super-conducting magnets systems - Why an LHC Hardware Commissioning? Specificity and complexity of this machine

The operation of the Large Hadron Collider relies many systems with technologies often beyond the start of the art and in particular on hundreds of superconducting magnets operating in superfluid He at 1.9K powered by more than 1700 power converters. A sophisticated magnet protection system is crucial to detect a quench and safely extract the energy stored in the circuits (about 1GJ only in one of the dipole circuits of each sector) after a resistive transition. In order to ensure safe operation, these systems depend on each other and on the infrastructure systems (controls, electricity distribution, water cooling, ventilation, communication systems, etc.). The commissioning of the technical systems together with the associated infrastructures is therefore mandatory. The complexity of operating this machine stems from the dependence and interplay of the systems, their nominal performance which is often at the technological frontier and on their geographical distribution.