The Cryogenic System for ITER

ITER cryogenic system is in its final design phase to be constructed at Cadarache, South of France. It shall use the most advanced cryogenic technologies developed for accelerators projects adapted and optimized to fulfill the requirements and constraints of a large fusion installation. A refrigeration capacity equivalent to 65 kW at 4.5 K is planned for the cooling of superconducting magnets, their HTS current leads and small users. It also includes the cooldown of the cryogenic pumps and their re-cooling after regeneration. A 1300 kW nitrogen plant provides cooling power for the thermal shields. The key design requirement is the capability to cope with large pulsed heat loads deposited in the magnets due to magnetic field variations and neutron production from the fusion reaction. The cryogenic distribution system is based on the design of a complex and compact transfer line system and several cryogenic distribution and feed boxes. After recalling the basic features we shall present the status of the design and the main magnet interfaces and key design requirements. (authors)