Author: Rutkowski, I.
Paper Title Page
WEPME009 Recent Developments of the European XFEL LLRF System 2941
 
  • Ch. Schmidt, G. Ayvazyan, V. Ayvazyan, J. Branlard, Ł. Butkowski, M.K. Grecki, M. Hoffmann, T. Jeżyński, F. Ludwig, U. Mavrič, S. Pfeiffer, H. Schlarb, H.C. Weddig, B.Y. Yang
    DESY, Hamburg, Germany
  • P. Barmuta, S. Bou Habib, K. Czuba, M. Grzegrzółka, E. Janas, J. Piekarski, I. Rutkowski, D. Sikora, Ł. Zembala, M. Żukociński
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  • W. Cichalewski, K. Gnidzińska, W. Jałmużna, D.R. Makowski, A. Mielczarek, A. Napieralski, P. Perek, A. Piotrowski, T. Pożniak, K.P. Przygoda
    TUL-DMCS, Łódź, Poland
  • S. Korolczuk, I.M. Kudla, J. Szewiński
    NCBJ, Świerk/Otwock, Poland
  • K. Oliwa, W. Wierba
    IFJ-PAN, Kraków, Poland
  
  The Eu­ro­pean XFEL is com­prised of more than 800 TESLA-type su­per-con­duct­ing ac­cel­er­a­tor cav­i­ties which are dri­ven by 25 high-power multi-beam kly­strons. For re­li­able, re­pro­ducible and main­tain­able op­er­a­tion of linac, the LLRF sys­tem will process more than 3000 RF chan­nels. Be­side the large num­ber of RF chan­nels to be processed, sta­ble FEL op­er­a­tion de­mands field sta­bil­ity bet­ter than 0.010deg in phase and 0.01% in am­pli­tude. To cope with these chal­lenges the LLRF sys­tem is de­vel­oped on MTCA.4 plat­form. In this paper, we will give an up­date of the lat­est elec­tron­ics de­vel­op­ments, ad­vances in the feed­back con­troller al­go­rithm and mea­sure­ment re­sults at FLASH.  
 
THPEA030 Improved Vector Modulator Card for MTCA-based LLRF Control System for Linear Accelerators 3207
 
  • I. Rutkowski, K. Czuba, M. Grzegrzólka
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  • D.R. Makowski, A. Mielczarek, P. Perek
    TUL-DMCS, Łódź, Poland
  • H. Schlarb
    DESY, Hamburg, Germany
  
  Mod­ern lin­ear ac­cel­er­a­tors re­quire high-pre­ci­sion RF field reg­u­la­tion of ac­cel­er­at­ing cav­i­ties. A crit­i­cal com­po­nent to achieve high-pre­ci­sion in the feed­back loop a Low Level Radio Fre­quency (LLRF) con­troller is the vec­tor mod­u­la­tor dri­ving the high power RF chain. At FLASH, the Free Elec­tron Laser in Ham­burg and Eu­ro­pean XFEL the LLRF con­trols are based on MTCA.4 plat­form. This paper de­scribes the con­cept, de­sign and per­for­mance of an im­proved vec­tor mod­u­la­tor mod­ule (DRTM-VM2). It is con­structed as Rear Tran­si­tion Mod­ule (RTM). The mod­ule con­sists of dig­i­tal, ana­log, di­ag­nos­tic and man­age­ment sub­sys­tems. FPGA from Xil­inx Spar­tan 6 fam­ily re­ceives data from con­trol mod­ule (AMC) using Multi-Gi­ga­bit Trans­ceivers (MGTs). The FPGA con­trols the ana­log part which in­cludes fast, high-pre­ci­sion DACs, I/Q mod­u­la­tor chips, pro­gram­ma­ble at­ten­u­a­tors, power am­pli­fier and fast RF gates for ex­ter­nal in­ter­lock sys­tem. Pin as­sign­ment on the Zone3 con­nec­tor is com­pli­ant with dig­i­tal class D1.2 rec­om­men­da­tions pro­posed by DESY. The de­sign has been op­ti­mized for mass pro­duc­tion and for easy ex­tends to wider fre­quency range. Elec­tronic switches offer soft­ware con­fig­u­ra­tion of power and clock sources.  
 
THPEA031 REGAE LLRF Control System Overview 3210
 
  • I. Rutkowski, Ł. Butkowski
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  • M. Hoffmann, H. Schlarb, Ch. Schmidt
    DESY, Hamburg, Germany
  
  The lin­ear ac­cel­er­a­tor REGAE (Rel­a­tivis­tic Elec­tron Gun for Atomic Ex­plo­ration) at DESY de­liv­ers elec­tron bunches with a few fem­tosec­ond du­ra­tion for time-re­solved in­ves­ti­ga­tion of ma­te­r­ial struc­tures in pump-probe con­fig­u­ra­tion. To achieve sub-10fs res­o­lu­tion, the Low Level RF con­trols for the nor­mal con­duct­ing S-band cav­i­ties must pro­vide field sta­bil­ity of .005% in am­pli­tude and of .005deg in phase. To achieve these de­mands, the re­cently de­vel­oped LLRF con­trol mod­ules based on the Mi­cro-Telecom­mu­ni­ca­tions Com­put­ing Ar­chi­tec­ture (MTCA.4) plat­form are used. For pre­cise field de­tec­tion and con­trol a rear tran­si­tion mod­ule (DRTM-DW­C8VM1) hous­ing 8 down-con­vert­ers and 1 vec­tor-mod­u­la­tor has been de­vel­oped. The down-con­verted sig­nals are trans­mit­ted to low-noise ADCs on an ad­vanced mez­za­nine card (SIS8300L) with two high speed DACs dri­ving the vec­tor-mod­u­la­tor. The on board FPGA de­vice runs the ad­vanced con­trol al­go­rithms with min­i­mum la­tency. Shot-to-shot learn­ing feed for­ward and ul­tra-fast ana­log and dig­i­tal feed­backs are ap­plied. In this paper, the first re­sults of the new RTM-AMC mod­ule pairs are pre­sented to­gether with the achieve­ments and lim­i­ta­tions on the RF field sta­bil­ity.