Installing a Fast Orbit Feedback at BESSY

In view of increased processing bandwidth at demanding experiments and the need for rapid compensation of noise spikes and new, yet unknown excitations, a fast orbit feedback aiming at noise suppression in the 1Hz 50Hz range has become mandatory for the 3rd generation light source BESSY II. The fast set point transmission plus the replacement of all corrector power supplies is scheduled as a first step. Later in combination with top up operation orbit stability can be further improved by replacing today s multiplexed analog beam position monitors by state of the art fast digital units. This paper describes how the pilot installation of a small subset of fast corrector power supplies allows to tune performance and study the benefits for today s most sensitive experiment

Fast Orbit Feedback at BESSY II Performance and Operational Experiences

At the 3rd generation light source BESSY II the first phase of a fast orbit feedback system has been completed and put into operation in 2012. In this first phase the aim was to achieve noise suppression in the 1Hz to several 10Hz range, mostly avoiding expensive upgrades to existing hardware, such as beam position monitors and the CAN based setpoint transmission to the power supplies. Only the power supplies were replaced with newer, faster versions. This paper describes the capability of the phase I FOFB with respect to beam motion transient suppression, low frequency damping and high frequency noise generation as well as aspects of operational integration and stabilit

Automated Operation of the MLS Electron Storage Ring

The Metrology Light Source MLS is in user operation since April 2008 working at energies ranging from 105 MeV up to 630 MeV, operating currents from a single electron up to 200 mA and different values for the momentum compaction factor. In parallel to machine commissioning, an automated finite state machine has been developed. This code knows, controls and coordinates a broad manifold of machine states and meanwhile has been evolved to an automated operator acting by itself on demand of a few high level commands. Actions range from plain device I O to complex transactions including filesystem operations and multiple device I O. The aim is to always keep machine and control system in a well defined state. We describe the program and report on the experience with the automated operation using this applicatio