ICALEPCS2011 - List of Authors (Luchini, K.)

Paper

Title

Page

Changing Horses Mid-stream: Upgrading the LCLS Control System During Production Operations

574

S. L. Hoobler, R.P. Chestnut, S. Chevtsov, T.M. Himel, K.D. Kotturi, K. Luchini, J.J. Olsen, S. Peng, J. Rock, R.C. Sass, T. Straumann, R. Traller, G.R. White, S. Zelazny, J. Zhou
SLAC, Menlo Park, California, USA

The control system for the Linac Coherent Light Source (LCLS) began as a combination of new and legacy systems. When the LCLS began operating, the bulk of the facility was newly constructed, including a new control system using the Experimental Physics and Industrial Control System (EPICS) framework. The Linear Accelerator (LINAC) portion of the LCLS was repurposed for use by the LCLS and was controlled by the legacy system, which was built nearly 30 years ago. This system uses CAMAC, distributed 80386 microprocessors, and a central Alpha 6600 computer running the VMS operating system. This legacy control system has been successfully upgraded to EPICS during LCLS production operations while maintaining the 95% uptime required by the LCLS users. The successful transition was made possible by thorough testing in sections of the LINAC which were not in use by the LCLS. Additionally, a system was implemented to switch control of a LINAC section between new and legacy control systems in a few minutes. Using this rapid switching, testing could be performed during maintenance periods and accelerator development days. If any problems were encountered after a section had been switched to the new control system, it could be quickly switched back.

Slides TUCAUST04 [0.183 MB]

FRBHAULT03

Beam-based Feedback for the Linac Coherent Light Source

1310

D. Fairley, K.H. Kim, K. Luchini, P. Natampalli, L. Piccoli, D. Rogind, T. Straumann
SLAC, Menlo Park, California, USA

Funding: Work supported by the U. S. Department of Energy Contract DE-AC02-76SF00515
Beam-based feedback control loops are required by the Linac Coherent Light Source (LCLS) program in order to provide fast, single-pulse stabilization of beam parameters. Eight transverse feedback loops, a 6x6 longitudinal feedback loop, and a loop to maintain the electron bunch charge were successfully commissioned for the LCLS, and have been maintaining stability of the LCLS electron beam at beam rates up to 120Hz. In order to run the feedback loops at beam rate, the feedback loops were implemented in EPICS IOCs with a dedicated ethernet multicast network. This paper will discuss the design, configuration and commissioning of the beam-based Fast Feedback System for LCLS. Topics include algorithms for 120Hz feedback, multicast network performance, actuator and sensor performance for single-pulse control and sensor readback, and feedback configuration and runtime control.

Slides FRBHAULT03 [1.918 MB]

Paper	Title	Page
TUCAUST04	Changing Horses Mid-stream: Upgrading the LCLS Control System During Production Operations	574
	S. L. Hoobler, R.P. Chestnut, S. Chevtsov, T.M. Himel, K.D. Kotturi, K. Luchini, J.J. Olsen, S. Peng, J. Rock, R.C. Sass, T. Straumann, R. Traller, G.R. White, S. Zelazny, J. Zhou SLAC, Menlo Park, California, USA
	The control system for the Linac Coherent Light Source (LCLS) began as a combination of new and legacy systems. When the LCLS began operating, the bulk of the facility was newly constructed, including a new control system using the Experimental Physics and Industrial Control System (EPICS) framework. The Linear Accelerator (LINAC) portion of the LCLS was repurposed for use by the LCLS and was controlled by the legacy system, which was built nearly 30 years ago. This system uses CAMAC, distributed 80386 microprocessors, and a central Alpha 6600 computer running the VMS operating system. This legacy control system has been successfully upgraded to EPICS during LCLS production operations while maintaining the 95% uptime required by the LCLS users. The successful transition was made possible by thorough testing in sections of the LINAC which were not in use by the LCLS. Additionally, a system was implemented to switch control of a LINAC section between new and legacy control systems in a few minutes. Using this rapid switching, testing could be performed during maintenance periods and accelerator development days. If any problems were encountered after a section had been switched to the new control system, it could be quickly switched back.
	Slides TUCAUST04 [0.183 MB]

FRBHAULT03	Beam-based Feedback for the Linac Coherent Light Source	1310
	D. Fairley, K.H. Kim, K. Luchini, P. Natampalli, L. Piccoli, D. Rogind, T. Straumann SLAC, Menlo Park, California, USA
	Funding: Work supported by the U. S. Department of Energy Contract DE-AC02-76SF00515 Beam-based feedback control loops are required by the Linac Coherent Light Source (LCLS) program in order to provide fast, single-pulse stabilization of beam parameters. Eight transverse feedback loops, a 6x6 longitudinal feedback loop, and a loop to maintain the electron bunch charge were successfully commissioned for the LCLS, and have been maintaining stability of the LCLS electron beam at beam rates up to 120Hz. In order to run the feedback loops at beam rate, the feedback loops were implemented in EPICS IOCs with a dedicated ethernet multicast network. This paper will discuss the design, configuration and commissioning of the beam-based Fast Feedback System for LCLS. Topics include algorithms for 120Hz feedback, multicast network performance, actuator and sensor performance for single-pulse control and sensor readback, and feedback configuration and runtime control.
	Slides FRBHAULT03 [1.918 MB]