A slow orbit feedback algorithm based on expanded response matrix for SSRF storage ring

Background Most of the global orbit feedback algorithms in storage rings are based on response matrix (RM) singular value decomposition method. Commonly, the RM is the orbit distortion along the ring responding to the steering magnet changes. For those methods RF frequency feedback is in a separated process. Methods and Results In this paper, the response matrix is expanded to the orbit distortion caused by the RF frequency variation. With this expanded RM, the orbit correction via steering magnet changes and RF frequency adjustment can be accomplished in one step. The commissioning results are carried out showing that the algorithm works stably.