Advances in the experimentation of extremum seeking techniques to maximize the RF power absorption in FTU

In this paper we report on the advances in the experimentation of extremum seeking techniques on the horizontal positioning system of the plasma in the Frascati Tokamak Upgrade (FTU). The dynamic extremum seeking technique had already shown very desirable results on the experimentation on one of the LH grills available at FTU. We report here on new experimental results where the experimentation is extended to two grills, consisting of a total of 2times8=16 waveguides. Additional results will be presented on the use of a modified extremum seeking algorithm to increase the robustness of the approach toward disturbances affecting the measurement of the reflected power. The experiments are carried out by relying on a reduced set of on-line measurements to keep the architecture of the control system simple. It is shown that the reduced measures are sufficient to gather the necessary information on the reflected power on each grill.