Speaker
Description
When a superconducting magnet has a local irreversible transition above the critical surface (quench), protection systems must be activated to avoid overheating the conductor or creating too large voltages in the coil between the resistive part the the superconductive one. Here we will deal with protection of high field main accelerator magnets, characterised by a large current density and long lengths, not allowing energy extraction. We will describe the physics ruling the hotspot temperature, with a flarameteric dependence on the magnet design, and the scaling laws for the quench detection. Finally we will describe the two main systems that are sued to protect the magnets, namely the quench heaters and the CLIQ, recently introduced at CERN.
