Dynamic study of a helium refrigerator for tokamak

Dynamic heat loads of the helium cryoplant of tokamak device due to operation of the magnet system, increase with the progress of the physics experiments, and may cause instability to the helium refrigerator. This paper presents the study of dynamic performance and behavior of EAST tokamak refrigerator from experiments and simulations. The dynamic effects on components depend on the variations of the heat loads and the ways to smooth and control of the system. This study aims to evaluate the stability of a helium refrigerator during high-current and long-pulsed plasma operation, discuss good methods to smooth the dynamic heat loads and to control the refrigerator. It will help to propose better operational way of the total helium cryogenic system in future.