Integral resonance control in continuous wave superconducting particle accelerators

Publikationstyp
Conference Paper
Date Issued
2020-07
Sprache
English
Author(s)
Bellandi, Andrea  
Branlard, Julien  
Eichler, Annika  
Pfeiffer, Sven  
TORE-URI
http://hdl.handle.net/11420/12750
Journal
IFAC-PapersOnLine  
Volume
53
Issue
2
Start Page
361
End Page
367
Citation
IFAC-PapersOnLine 53 (2): 361-367 (2020)
Contribution to Conference
21st IFAC World Congress 2020  
Publisher DOI
10.1016/j.ifacol.2020.12.186
Scopus ID
2-s2.0-85104498995
Publisher
Elsevier
Superconducting accelerating cavities for continuous wave low-current particle accelerators requires a tight resonance control to optimize the RF power costs and to minimize the beam delivery downtime. When the detuning produced by radiation pressure becomes comparable to the RF bandwidth, the monotonic instability starts to affect the cavity operation. When this instability is triggered by external vibrations or drifts, the accelerating field amplitude drops rapidly, and the beam acceleration has to be stopped. Past experiments showed that using an integral control of the piezoelectric tuners installed on the cavity prevents the adverse effects of the monotonic instability. This paper derives theoretically why an integral controller is an effective way to counteract the monotonic instability. To perform the study a linearized state-space model of the cavity is derived. Simulations and experiments in a superconducting test facility indicate that the use of this kind of control has the additional benefit of bringing the cavities to the resonance condition automatically.
Subjects
Control systems
Electromagnetic devices
Parametric resonances
Particle accelerators
DDC Class
004: Informatik
600: Technik