Circuit modeling and analysis of matching configurations for the DTT ICRF system

In Ion Cyclotron Range of Frequencies (ICRF) systems, transmission lines, based on rigid coaxial cables, deliver the power from the radiofrequency generators to the antennas, matching the impedances to protect the generator, and maximizing the power transfer to the plasma. This work performs such an analysis, employing a circuital approach to evaluate different matching configurations, checking the maximum voltage all over the cables and avoiding heavy electromagnetic simulation for a quick and easy comparison. Simulations were run for the ICRF system of the Divertor Tokamak Test facility (DTT) using the circuit simulation tool of Ansys Electronic Desktop. After choosing which circuit fits the best in this application, the whole antenna matching circuit was modelled and verified through the active S-parameters. The analysis has proceeded by drawing the ELM resilient schemes for two antennas with -3dB hybrid couplers, showing the power reflected into the dummy load varying the power ratio and the phasing between the straps by a source tapering of amplitude and phase at the generator.