Author: Yuan, Q.
Paper Title Page
MOPFI046 Transverse RF Kicker Excitation and Longitudinal RF Noise Diffusion for Slow Extraction from SAPT 386
 
  • L. Ouyang, M. Gu, D.M. Li, Q. Yuan, M.Z. Zhang
    SINAP, Shanghai, People's Republic of China
  
  Two key tech­niques used in the slow ex­trac­tion from syn­chro­tron ac­cel­er­a­tor: lon­gi­tu­di­nal RF sto­chas­tic noise ac­cel­er­a­tion, and trans­verse RF knock out ex­ci­ta­tion have been stud­ied in this paper. De­tailed com­par­i­son have re­vealed the po­ten­tials and lim­its of both meth­ods. For the lon­gi­tu­di­nal RF sto­chas­tic ac­cel­er­a­tion ex­ci­ta­tion, the focus has been the phase space com­pres­sion of par­ti­cles, which makes the them to has­ten around the RF bucket of the cav­ity, thus to lower the sen­stiv­ity to rip­ple. For the trans­verse RF knock out ex­ci­ta­tion, the em­pha­sis have been op­ti­mal schemes of am­pli­tude mod­u­la­tion and fre­quency mod­u­la­tion of the RF sin­gals. The op­ti­miza­tions are also used to lower the sen­stiv­ity of the beam to the rip­ple and to en­hance the uni­for­mity of the ex­tracted beam.  
 
WEPWA032 The Feed-forward Control Design of Correction Coil Power Supply for SSRF EPU 2199
 
  • Q. Yuan, M. Gu, G.Y. Jiang, R. Wang
    SINAP, Shanghai, People's Republic of China
  
  The SSRF El­lip­ti­cally Po­lar­ized Un­du­la­tor (EPU) has been in op­er­a­tion for about three years. The feed-for­ward con­trol al­go­rithm of cor­rec­tion coil power sup­ply (CCPS) is im­ple­mented in the Input and Out­put Con­troller (IOC) based on VME. The cor­rec­tion cur­rent re­sponds not fast enough to gap move­ment, mainly be­cause the com­mu­ni­ca­tion be­tween IOC and dig­i­tal CCPS tak­ing up much time. This paper in­tro­duces one new feed-for­ward de­sign, that is ,on the one hand, the CCPS cur­rent re­sponds to both gap move­ment and shift move­ment ac­cord­ing to 2D Look-up Table(LUT) by lin­ear in­ter­po­la­tion method. On the other hand, feed-for­ward con­trol al­go­rithm is car­ried out in the EPU con­troller, and the CCPS with fast con­trol re­sponse is di­rectly con­trolled by PLC through ana­log in­ter­face. Thus, the cor­rec­tion cur­rent re­spond well to gap and shift move­ment owing to leav­ing out com­mu­ni­ca­tion time.