The LCLS-II LLRF System

Conference · Tue Sep 01 00:00:00 EDT 2015

OSTI ID:1223483

DooLittle, Lawrence ^[1]; Huang, G. ^[1]; Ratti, A. ^[1]; Serrano, C. ^[1]; Bachimanchi, Ramakrishna ^[2]; Hovater, J. Curt ^[2]; Babel, S. ^[3]; Hong, B. ^[3]; Van Winkle, D. ^[3]; Chase, B. ^[4]; Cullerton, E. ^[5]; Varghese, P. ^[5]

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1. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
2. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
3. SLAC National Accelerator Lab., Menlo Park, CA (United States)
4. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
5. FNAL, Batavia, IL

The SLAC National Accelerator Laboratory is planning an upgrade (LCLS-II) to the Linear Coherent Light Source with a 4 GeV CW superconducting (SCRF) linac. The SCRF linac consists of 35 ILC style cryomodules (eight cavities each) for a total of 280 cavities. Expected cavity gradients are 16 MV/m with a loaded Q_L of ~ 4x10⁷. The RF system will have 3.8 kW solid state amplifiers driving single cavities. To ensure optimum field stability a single-source single-cavity control system has been chosen. It consists of a precision four-channel cavity receiver and RF stations (Forward, Reflected and Drive signals). In order to regulate the resonant frequency variations of the cavities due to He pressure, the tuning of each cavity is controlled by a Piezo actuator and a slow stepper motor. In addition the system (LLRF-amplifier-cavity) is being modeled and cavity microphonic testing has started. This paper describes the LLRF system under consideration, including recent modeling and cavity tests.

• Research Organization: SLAC National Accelerator Lab., Menlo Park, CA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 1223483
• Report Number(s): JLAB-ACE-15-2107; DOE/OR/23177-3550; TRN: US1601449
• Resource Relation: Conference: IPAC 2015, Richmond, VA (United States), 3-8 May 2015
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
SUPERCONDUCTING CAVITY RESONATORS
STANFORD LINEAR ACCELERATOR CENTER
AMPLIFIERS
ELECTRIC MOTORS
LINEAR ACCELERATORS
GEV RANGE 01-10
LIGHT SOURCES
CONTROL SYSTEMS
RF SYSTEMS
ACTUATORS
PLANNING
SIMULATION
TESTING
TUNING
FREQUENCY CONTROL