Author: Muguira, L.
Paper Title Page
MOPPR041 Design and Measurements of the Stripline BPM System of the ESS-BILBAO 870
 
  • D. Belver, J. Feuchtwanger, N. Garmendia, P.J. González, L. Muguira, S. Varnasseri
    ESS Bilbao, LEIOA, Spain
  • F.J. Bermejo
    Bilbao, Faculty of Science and Technology, Bilbao, Spain
  • V. Etxebarria, J. Jugo, J. Portilla
    University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
 
  A new design for the Beam Position Monitors (BPMs) diagnostics of ESS-Bilbao, consisting of a whole block of stripline sensors, has been designed and manufactured. The design is based on travelling wave principles to detect the position of the beam in the vacuum chamber. The length of the stripline is 200 mm and the coverage angle is 0.952 rad. The position of the internal tube simulating the beam can be changed with respect to the outer tube within a range of 20 mm approximately for both X and Y axis, with a resolution less than 10 μm. The characteristics of the block with and without beam are measured and evaluated at frequencies of 175 and 352 MHz, using the electronics system developed for the BPM capacitive pick-ups. This electronics system is divided in an Analog Front-End (AFE) unit, where the signals are conditioned and converted to baseband, and a Digital Unit (DU) to sample them and calculate the position and phase of the beam. In this contribution, the performed tests will be fully described and the results also discussed.  
 
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.