Upgraded closed orbit distortion system and its application in Hefei light source

The paper presents an upgraded close orbit distortion(COD) system and its application in phase II project of HLS, and introduces Bergoz's modules for COD signal process. The upgraded COD system, with resolution of processing electronics circuit up to 1μm and repetition error of system not greater than 10μm, is operated in routine. The measurement of dispersion validated the reliability of upgraded COD system. We have completed to position the beam in the magnetic center of a quadrupole using the high precision COD system and the beam based alignment system. We have accomplished global close orbit correction system and its application on line. The improved beam quality can provide a stable light source for users.