Integration of orbit control with real-time feedback (original) (raw)

User Operation and Upgrades of the Fast Orbit Feedback at the SLS

Proceedings of the 2005 Particle Accelerator Conference, 2005

A report on the performance of the fast orbit feedback (FOFB) in its 2nd year of user operation is given. Photon beam position monitors (XBPM) have been included by means of a slow feedback which changes the reference settings of the FOFB. Users are permitted to change the XBPM references within certain limits while the feedback is running. A fast synchronous readout of the XBPMs allows their integration into the FOFB loop. The FOFB will be extended by an additional beam position monitor (BPM) in order to satisfy the requirements of the upcoming FEMTO project.

Design of a fast global orbit feedback system for the Advanced Light Source

PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268), 2000

The fast stability of the closed orbit of the electron beam at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory fulfills user requirements so far without any fast active correction system. In the range between 0.1 and 500 Hz the integrated rms closed orbit motion is significantly below one tenth of one sigma beamsizes. For the future there is some user demand to improve this stability further. Moreover, the expansion of the capabilities of the ALS creates new sources of closed orbit noise. Therefore the design of a fast, global orbit feedback system has been started in conjunction with a general upgrade of the ALS control system. It will initially operate with an update rate of 500 Hz-1 kHz, will include 24 beam position monitors and corrector magnets in each plane and will use standard computer and networking architecture. The system design, measurements of transfer functions and tests with small prototype systems will be presented.

Architecture of the APS Real-Time Orbit Feedback System

The APS Real-Time Orbit Feedback System is designed to stabilize the orbit of the stored positron beam against low-frequency sources such as mechanical vibration and power supply ripple. A distributed array of digital signal processors is used to measure the orbit and compute corrections at a 1kHz rate. The system also provides extensive beam diagnostic tools. This paper describes the architectural aspects of the system and describes how the orbit correction algorithms are implemented. 1 Introduction The APS is the foremost third-generation synchrotron light source in the United States, delivering intense x-rays to as many as 35 insertion-device and 35 bending-magnet beamlines. As with other light sources, orbit stability is critical in order to achieve the optimum performance for the x-ray users. At APS the rms orbit motion must not exceed 5% of the beam size, translating to limits of 17m rms horizontally and 4.5m rms vertically. The APS real-time orbit feedback system provides rea...

Real-Time Orbit Feedback at the APS

A real-time orbit feedback system has been implemented at the Advanced Photon Source in order to meet the stringent orbit stability requirements. The system reduces global orbit motion below 30 Hz by a factor of four to below 5 l.trn rms horizontally and 2 pm rms vertically. This paper focuses on dynamic orbit stability and describes the all-digital orbit feedback system that has been implemented at the APS. Implementation of the global orbit feedback system is described and its latest performance is presented. Ultimately, the system will provide local feedback at each x-ray source point using installed photon BPMs to measure x-ray beam position and angle directly. Technical challenges associated with local feedback and with dynamics of the associated corrector magnets are described. The unique diagnostic capabilities provided by the APS system are discussed with reference to their use in identifying sources of the underlying orbit motion.

Commissioning results of the fast orbit feedback at the ALS

Proceedings of the 2003 Bipolar/BiCMOS Circuits and Technology Meeting (IEEE Cat. No.03CH37440), 2003

A new fast global orbit feedback system has been designed at the ALS and is in commissioning since last September. The system has two main purposes. The first is to meet the demands of some users for even improved short term orbit stability. The second is to enable the use of more sophisticated insertion device compensation schemes (e.g. tune, beta-beating, coupling) for fast moving insertion devices like elliptically polarizing undulators, without deteriorating the orbit stability. One feature of the fast orbit feedback (with 1 kHz update rate) is the use of standard computer and networking equipment. 0-7803-7739-9 ©2003 IEEE

Design of a fast orbit feedback for SOLEIL

SOLEIL is a third generation light source under construction. Great care is taken at all levels of the machine design in order to reach beam stability at the micrometer level. In particular, a fast global closed-orbit feedback is foreseen for suppressing remaining beam vibrations up to 100 Hz.

Operational Experience Integrating Slow and Fast Orbit Feedbacks at the Als

2004

A fast global orbit feedback system has been imple- mented at the ALS and is being used during user opera- tion since this year. The system has two main purposes. The first is to meet the demands of some users for even im- proved (submicron) short term orbit stability. The second is to enable the use of more sophisticated insertion

Use of a simple storage ring simulation for development of enhanced orbit correction software

At the Advanced Photon Source (APS) most of the testing of minor operational software is done during accelerator studies time. For major software changes, such as the porting of the complex workstation-based orbit control software to an EPICS IOC, much of the testing was done "offline" on a test IOC. A configurable storage ring simulator was created in a workstation with corresponding control system records for correctors and orbit readbacks.

Commissioning Results of Slow Orbit Feedback Using Pid Controller Method for Siam Photon Source

Presented at, 2012

A slow orbit feedback (SOFB) system has been developed to improve the orbit stability of the Siam Photon Source (SPS) storage ring. The SOFB uses a PID controller method utilizing LabVIEW channel to access 20 BPMs and 28 correctors of the ring. The first phase implementation of the feedback loops based on this method was operated at 0.05Hz sampling frequency, which reduces the fluctuation of both horizontal and vertical positions of the orbit from ~100-200 microns down to ~15-30 microns. The commissioning results indicate that further work and hardware upgrade are required. A higher sampling frequency up to 30-50Hz is strongly necessary for PID controller implementation. Upgrading of the existing 12-bit resolution corrector power supplies is also needed. The basic principle of PID algorithms, hardware, software and commissioning results of the current SOFB system, as well as future development plans, will be presented.

ORBIT FEEDBACK DEVELOPMENT AT THE ALS

The slow orbit feedback system at the ALS has been continually improved over the years. The most recent upgrades were the incorporation of an RF-frequency feedback and the switch to higher resolution digital to analog converters (DACs). In addition all readouts of beam position monitors (BPMs) and most of the controls for corrector magnet power supplies were ported to a new control system based on compact PCI (cPCI) intelligent output controllers (IOCs). These upgrades were part of the implementation of a new fast global orbit feedback system which has been designed over the last year and a half and is entering its commissioning stage. One feature of the fast orbit feedback (with 1 kHz update rate) is the use of standard computer and networking equipment.