Abstract
The system analyses of the magnetic field control system in the International Thermonuclear Experimental Reactor (ITER) are described. The analyses are performed by using a model of the closed loop system, which consists of the data analysis of diagnostics, the controller, the power supply of coils and the tokamak plant. The characteristics of the magnetic field control system in ITER are discussed and it is shown that the control system designed during the ITER engineering design activities satisfies its requirements. The important roles of eddy currents in optimizing the magnetic field control system in ITER are also discussed.