LINAC2022 - List of Authors (Leyge, J.F.)

Paper	Title	Page
MOPOPA15	Three Years of Operation of the SPIRAL2 SC LINAC- RF Feedback	98
	M. Di Giacomo, M. Aburas, P.-E. Bernaudin, O. Delahaye, A. Dubosq, A. Ghribi, J.-M. Lagniel, J.F. Leyge, G. Normand, A.K. Orduz, F. Pillon, L. Valentin GANIL, Caen, France F. Bouly LPSC, Grenoble Cedex, France S. Sube CEA-DRF-IRFU, France
	The superconducting LINAC of SPIRAL2 at the GANIL facility has been in operation since October 2019. The accelerator uses 12 low beta and 14 high beta supercon-ducting quarter wave cavities, cooled at 4°K, working at 88 MHz. The cavities are operated at a nominal gradient of 6.5 MV/m and are independently powered by a LLRF and a solid-state amplifier, protected by a circulator. Pro-ton and deuteron beam currents can reach 5 mA and beam loading perturbation is particularly strong on the first cavities, as they are operated at field levels much lower than the nominal one. This paper presents a feedback after three years of oper-ation, focuses on the RF issues, describing problems and required improvement on the low level, control and pow-er systems
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOPA15
About •	Received ※ 14 August 2022 — Revised ※ 17 August 2022 — Accepted ※ 01 September 2022 — Issue date ※ 02 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPA13	Superconducting Cavity and RF Control Loop Model for the SPIRAL2 Linac	767
	F. Bouly LPSC, Grenoble Cedex, France M. Di Giacomo, J.F. Leyge, M. Tontayeva GANIL, Caen, France
	The SPIRAL2 superconducting linac has been successfully commissioned with protons in 2020. During the commissioning, a model of the cavity and its LLRF control loop has been developed. The model enables to have better understanding of the system and was used to guide the tuning of the PI(D) correctors for beam loading compensation. Here we review the development of such a tool, computed with MATLAB Simulink and using the frequency domain (Laplace transfer function) to model the cavity RF and mechanical behaviours (Lorentz detuning), as well as all elements that compose the RF control loop (digital LLRF, amplifier, transmission lines, etc.). The benchmarking of the model with measurement carried out with the proton beam is also discussed in this contribution.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-THPOPA13
About •	Received ※ 24 August 2022 — Revised ※ 01 September 2022 — Accepted ※ 03 September 2022 — Issue date ※ 15 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Three Years of Operation of the SPIRAL2 SC LINAC- RF Feedback

98

M. Di Giacomo, M. Aburas, P.-E. Bernaudin, O. Delahaye, A. Dubosq, A. Ghribi, J.-M. Lagniel, J.F. Leyge, G. Normand, A.K. Orduz, F. Pillon, L. Valentin
GANIL, Caen, France
F. Bouly
LPSC, Grenoble Cedex, France
S. Sube
CEA-DRF-IRFU, France

The superconducting LINAC of SPIRAL2 at the GANIL facility has been in operation since October 2019. The accelerator uses 12 low beta and 14 high beta supercon-ducting quarter wave cavities, cooled at 4°K, working at 88 MHz. The cavities are operated at a nominal gradient of 6.5 MV/m and are independently powered by a LLRF and a solid-state amplifier, protected by a circulator. Pro-ton and deuteron beam currents can reach 5 mA and beam loading perturbation is particularly strong on the first cavities, as they are operated at field levels much lower than the nominal one. This paper presents a feedback after three years of oper-ation, focuses on the RF issues, describing problems and required improvement on the low level, control and pow-er systems

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOPA15

About •

Received ※ 14 August 2022 — Revised ※ 17 August 2022 — Accepted ※ 01 September 2022 — Issue date ※ 02 September 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPA13

Superconducting Cavity and RF Control Loop Model for the SPIRAL2 Linac

767

F. Bouly
LPSC, Grenoble Cedex, France
M. Di Giacomo, J.F. Leyge, M. Tontayeva
GANIL, Caen, France

The SPIRAL2 superconducting linac has been successfully commissioned with protons in 2020. During the commissioning, a model of the cavity and its LLRF control loop has been developed. The model enables to have better understanding of the system and was used to guide the tuning of the PI(D) correctors for beam loading compensation. Here we review the development of such a tool, computed with MATLAB Simulink and using the frequency domain (Laplace transfer function) to model the cavity RF and mechanical behaviours (Lorentz detuning), as well as all elements that compose the RF control loop (digital LLRF, amplifier, transmission lines, etc.). The benchmarking of the model with measurement carried out with the proton beam is also discussed in this contribution.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-THPOPA13

About •

Received ※ 24 August 2022 — Revised ※ 01 September 2022 — Accepted ※ 03 September 2022 — Issue date ※ 15 September 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)