Author: Verdu, J.
Paper Title Page
WEPPD070 Automatic Tuner Unit Operation for the Microwave System of the ESS-Bilbao H+ Ion Source 2684
  • L. Muguira, I. Arredondo, D. Belver, M. Eguiraun, F.J. Fernandez Huerta, J. Feuchtwanger, N. Garmendia, O. González, P.J. González
    ESS Bilbao, LEIOA, Spain
  • V. Etxebarria, J. Jugo, J. Portilla
    University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
  • J. Verdu
    EPFL, Lausanne, Switzerland
  Funding: The present work is supported by the Basque Government and Spanish Ministry of Science and Innovation.
The operation of the waveguide automatic tuner unit (ATU) for optimizing the impedance matching and the RF power coupling in the ESS-Bilbao H+ Ion Source (ISHP) is presented. Since the plasma chamber can be considered as a time varying load impedance for the pulsed RF 2.7 GHz high power generator, several approaches have been studied for accurately measuring the load impedance. In the later case, a set of power detectors connected to electric field probes, IQ demodulators and gain/phase detectors connected to dual directional couplers have been integrated. An experimental comparison of these approaches is presented, showing their accuracy, limitations and error-correction methods. Finally, the control system developed for the automatic operation of the triple capacitive post tuner is described, as well as illustrative results.