Author: Harumatsu, K.
Paper Title Page
WEPME014 Progress in Development of New LLRF Control System for SuperKEKB 2953
 
  • T. Kobayashi, K. Akai, K. Ebihara, A. Kabe, K. Nakanishi, M. Nishiwaki, J.-I. Odagiri
    KEK, Ibaraki, Japan
  • H. Deguchi, K. Harumatsu, K. Hayashi, T. Iwaki, J. Mizuno, J. Nishio, M. Ryoshi
    Mitsubishi Electric TOKKI Systems, Amagasaki, Hyogo, Japan
  
  For the Su­perKEKB pro­ject, a new LLRF con­trol sys­tem was de­vel­oped to re­al­ize high ac­cu­racy and flex­i­bil­ity. It is an FPGA-based dig­i­tal RF feed­back con­trol sys­tem using 16-bit ADC's, which works on the μTCA plat­form. The FPGA boards con­trol ac­cel­er­at­ing cav­ity fields and cav­ity tun­ing, and the EPICS-IOC is em­bed­ded in each of them. The CSS-BOY was adopted for a user in­ter­face of our sys­tem. High power test of the new LLRF con­trol sys­tem was per­formed with the ARES Cav­ity of KEKB. The ob­tained feed­back con­trol sta­bil­ity with a kly­stron drive was suf­fi­cient as well as the low-level eval­u­a­tion re­sult. And auto tuner con­trol also worded suc­cess­fully. The start-up se­quencer pro­gram for the cav­ity op­er­a­tion and auto-ag­ing pro­gram also worked very well. The tem­per­a­ture char­ac­ter­is­tics of the sys­tem de­pend largely on band-pass fil­ters (BPF). We tried to tune the BPF to re­duce the tem­per­a­ture co­ef­fi­cient. Con­se­quently the tem­per­a­ture de­pen­dence was im­proved to sat­isfy the re­quired sta­bil­ity.