Control Methodology and Test Modes During the Qualification Test of the ITER Cold Circulator

Abstract Supercritical helium cold circulators operating at unprecedented high mass flow rates are required to maintain the ITER magnet and cryopump system at operating conditions. The qualification test plan has been developed for the two cold circulators installed in the Test Auxiliary Cold Box in compliance with the Japan Atomic Energy Agency cryogenic test facility consisting of a cryoplant of ∼ 5 kW at 4.5 K. The process modelling for test modes such as cool-down/warm-up, nominal and 10% higher speed operation, including test approach, assumptions made, and expected results using the control strategies to be implemented during the test are described.