Orbit stabilization for the new insertion devices in SSRF

Abstract

Abstract During the Shanghai Synchrotron Radiation Facility (SSRF) beamline project, fourteen new insertion devices (IDs) have been successfully installed and transitioned to operation. However, these new IDs led to considerable closed orbit distortions in the SSRF storage ring. In the canted beamlines, the theoretical current values of dipoles required for the closed dual-canted angle were established, however, errors in the actual machine make a significant effect on closed orbit. To address this, an adjustment configuration, based on the response matrix, was developed for the closed dual-canted angles. Additionally, an orbit feedforward compensation system equipped with corrector coils, was employed. As a result, the maximum horizontal and vertical orbit distortions induced by the IDs were successfully decreased to less than 5.0 μm and 3.5 μm, respectively. Furthermore, a specialized local fast feedback system was designed to maintain the precise orbit and angle stability for the Hard X-ray Nanoprobe beamline.