QUENCH HEATER EXPERIMENTS ON THE LHC MAIN SUPERCONDUCTING MAGNETS

In case of a quench in one of the main dipoles and quadrupoles of CERN's Large Hadron Collider (LHC), the magnet has to be protected against excessive temperatures and high voltages. In order to uniformly distribute the stored magnetic energy in the coils, heater strips installed in the magnet are fired after quench detection. Tests of different quench heater configurations were performed on various 1 m long model and 15 m long prototype dipole magnets, as well as on a 3 m long prototype quadrupole magnet. The experiments aimed at optimising the layout of the quench heater strips, minimising the complexity of the protection system and determining its redundancy. In this paper we discuss the results of the performed experiments and describe the optimised quench heater design for the LHC main magnets.