Simulation of the Antenna–Plasma Coupling Efficiency of the Three-Loop ICR Antenna of the T-15MD Tokamak

Currently, the National Research Center “Kurchatov Institute” is developing an ion-cyclotron resonance (ICR) heating system for the T-15MD tokamak. The ICRF (ion cyclotron range of frequency) system is to be used to heat the ion component of the plasma and generate a non-inductive current (drag current). The total power of the system is 6 MW with a pulse duration of up to 30 s. Under these parameters, reflected power could lead to failure of the ion-cyclotron resonance heating (ICRH) of the system. Therefore, matching the load (plasma) to the generator requires special attention. This work presents a numerical study of the antenna–plasma coupling efficiency for a three-loop antenna developed for ICRF plasma heating in the T‑15MD tokamak. The dependence of the antenna impedance on plasma parameters, its position, and the phasing of the antenna excitation currents is studied.