Requirements and Interfaces to Cryogenic and Power Supply Plants for the ITER Magnet System

Abstract

This paper describes the requirements and interfaces of cryogenic and power supply plants for the ITER magnet system. The heat loads and mass flow rates of the magnet system is evaluated to keep coil temperature within 6.5 K during the plasma operation of 2200 s. The helium consumption in the current leads is estimated for a current feed of 4.5 MA from 4 K to 300 K. The location of the electrical insulation breaks is compared near winding and outside of cryostat. The terminal box is designed for interfacing the cryogenic and power supply systems. Separate vacuums for the cryostat and the cryolines facilitate maintenance of all cryogenic components without warm-up of the whole system. A superconducting busbar is used to supply current from a current connector at the coil to the vapor-cooled lead in the coil terminal box. The layout of cryogenic lines and equipment is designed to consider space limitations and routing restrictions in the tokamak hall and the electrical termination building. The main parameters of the cryogenic plant (cryoplant) are discussed.