CERN Beam Interlock Redundant Dump Trigger Module Performance during LHC Run 2

During the Long Shutdown 1 an additional link between the Beam Interlocks System and the LHC Beam Dumping System was installed. This third channel is a direct access from the BIS to the asynchronous dump triggering lines. This paper describes the experience collected for the first 10 months of operation and the improvements proposed for a future upgrade of the module

Analysis of the Dependability of the LHC Quench Detection System During LHC Run 2 and Further System Evolution

The quench detection system (QDS) of the LHC superconducting circuits is an essential part of the LHC machine protection and ensures the integrity of key elements of the accelerator. The large amount of hardwired and software interlock channels of the QDS requires a very high system dependability in order to reduce the risk of affecting the successful operation of the LHC. This contribution will present methods and tools for systematic fault tracking and analysis, and will discuss recent results obtained during the LHC production run in 2016. Measures for maintaining and further improving of the system performance will be explained. An overview of the further evolution of the LHC QDS also in view of the upcoming High Luminosity Upgrade of the LHC will be given

An Enhanced Quench Detection System for Main Quadrupole Magnets in the Large Hadron Collider

To further improve the performance and reliability of the quench detection system (QDS) for main quadrupole magnets in the Large Hadron Collider (LHC), there is a planned upgrade of the system during the long shutdown period of the LHC in 2019-2020. While improving the already existing functionalities of quench detection for quadrupole magnets and field-bus data acquisition, the enhanced QDS will incorporate new functionalities to strengthen and improve the system operation and maintenance. The new functionalities comprise quench heater supervision, interlock loop monitoring, power cycling possibility for the whole QDS and its data acquisition part, monitoring and synchronization of trigger signals, and monitoring of power supplies. In addition, the system will have two redundant power supply feeds. Given that the enhanced QDS units will replace the existing QDS units in the LHC tunnel, the units will be exposed to elevated levels of ionizing radiation. Therefore, it is necessary to design a radiation tolerant detection system. In this work, an overview of the design solution for such enhanced QDS is presented

Quench detection and diagnostic systems for the superconducting circuits for the HL-LHC

The High Luminosity Upgrade of the LHC [1] will incorporate a new generation of superconducting elements such as high field superconducting magnets based on Nb$_3$Sn conductors and MgB$_2$ high temperature superconducting links for magnet powering. The proper protection and diagnostics of those elements require the development of a new generation of integrated quench detection and data acquisition systems as well as novel methods for quench detection. The next generation of quench detection systems is to a large extent software defined and serves at the same time as high performance data acquisition system

A Statistical Analysis of Electrical Faults in the LHC Superconducting Magnets and Circuits

The large hadron collider (LHC) at CERN has been operating and generating physics experimental data since September 2008, and following its first long shut down, it has entered a second, 4-year-long physics run. It is to date the largest superconducting installation ever built, counting over 9000 magnets along its 27-km long circumference. A significant operational experience has been accumulated, including the occurrence and consequences of electrical faults at the level of the superconducting magnets, as well as their protection and instrumentation circuits. The purpose of this paper is to provide a first overview of the most common electrical faults and their frequency of occurrence in the first years of operation, and to perform a statistical analysis that can provide reference values for future productions of similar dimensions and nature

A New Cryogenic Test Facility for Large and Heavy Superconducting Magnets

CERN has recently designed and constructed a new cryogenic facility for testing large and heavy superconducting magnets at liquid helium temperatures. The facility, erected in a large assembly hall with cranes capable of up to 100 t, provides a cooling capacity of 1.2 kW at 4.5 K equivalent, 15-kW LN$_2$ cooling and warming capabilities for up to three magnets in parallel. The facility provides the required technical infrastructure for continuous and reliable operation. Test capabilities comprise electrical, cryogenics, vacuum and mechanical verification, and validation at ambient and liquid helium temperatures. A comprehensive survey and magnetic measurement system, comprising a hall-probe mapper, a rotating-coil magnetometer, a stretched wire, a translating fluxmeter, and a laser tracker, allows the detailed measurement of the magnetic field strength and quality on a large volume. The magnetic axes of the quadrupoles can be established within $\pm 0.2$ mm at $1 \sigma$ accuracy. The facility has been equipped with power supplies, three converters of $\pm 500$ A/120 V, and six converters of $\pm 600$ A/40 V, as well as the required energy extraction, quench protection, data acquisition, and interlocks for the testing of superconducting magnets for the FAIR project, currently under construction at the GSI Research Center, in Darmstadt, Germany. The versatile design of the facility, its layout, and testing capabilities complements CERN's other test infrastructures for large superconducting magnets. We report on the design, construction, and commissioning of the facility as well as the expected capabilities and performances for future tests of large and heavy superconducting magnets