Preliminary analysis of the external matching unit for the ICRH system for FAST

The Fusion Advanced Studies Torus (FAST) is a new tokamak machine proposed by the Italian Fusion Association as a Satellite Tokamak for accompanying the ITER programme. A relevant objective of FAST is to study burning plasma issues by simulating the alpha particle dynamics by means of fast ions produced by acceleration of a minority species using an Ion Cyclotron Resonance Heating (ICRH) system. A maximum coupled power of 30 MW is foreseen in the 60–90 MHz frequency range. The load tolerant External Conjugate-T (ECT) concept is being studied to match the low impedance of the launcher to the feeding coaxial cables (Z0 = 30 Ω). A preliminary design of the external tuning and matching system has been made and their simulation results are given in the paper.