LINAC2018 - List of Keywords (FPGA)

Paper	Title	Other Keywords	Page
MOPO041	Performance Test Results of Magnet Power Supply	controls, interface, power-supply, experiment	118
	K.-H. Park, J.H. Han, S.-H. Jeong, Y.G. Jung, D.E. Kim, M.J. Kim, H.-G. Lee, S.B. Lee, B.G. Oh, H.S. Suh PAL, Pohang, Kyungbuk, Republic of Korea
	A high stable magnet power supply (MPS) was developed, which was a bipolar type with 200A of the output current at the 40V of output voltage. The MPS has been implemented by the digital signal processing technology using the DSP, FPGA, ADCs and so on. The output current stability of the MPS showed about 6ppm peak-to-peak in a short term experiment at 200A of its full output current. The long term stability was shown in 15 ppm peak-to-peak for 10 hours at 200A. And the others experimental results about the MPS were shown in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO041
About •	paper received ※ 31 August 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO107	Performance Evaluation of the RF Reference Phase Stabilization System on Fiber-optical Link for KEK e⁻/e⁺ Injector LINAC	feedback, linac, controls, EPICS	230
	N. Liu, B. Du Sokendai - Hayama, Hayama, Japan D.A. Arakawa, H. Katagiri, T. Matsumoto, S. Michizono, T. Miura, F. Qiu, Y. Yano KEK, Ibaraki, Japan T. Matsumoto, T. Miura, F. Qiu Sokendai, Ibaraki, Japan
	KEK e⁻/e⁺ injector is the 600 m J-shaped LINAC which has 8 RF sectors. Stabilization of RF phase reference for long distance transmission is necessary for stable RF operation. In the present system, single-mode fiber-optical links without feedback control are used from sector 2 to 5. For the SuperKEKB, the phase stability requirement is within 0.1 deg. rms. The more stable RF phase reference is necessary to improve the phase stability. In this paper, a feedback control system for RF reference phase stabilization is tested for system performance evaluation. The temperature and humidity characteristics of the electric and optical components and phase stabilized optical fiber (PSOF) with different wavelengths will also be presented.
	Poster MOPO107 [2.026 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO107
About •	paper received ※ 12 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO111	Development of New LLRF System at the J-PARC Linac	LLRF, linac, low-level-rf, feedback	233
	K. Futatsukawa, Z. Fang, Y. Fukui KEK, Ibaraki, Japan Y. Sato Nippon Advanced Technology Co., Ltd., Tokai, Japan S. Shinozaki JAEA/J-PARC, Tokai-mura, Japan
	In the J-PARC linac, the LLRF system with the digital feedback (DFB) and the digital feedforward (DFF) was adopted for satisfying requirement of amplitude and phase stabilities. It has been operated without serious problems. However, it has been used since the beginning of the J-PARC and more than ten years have already passed since the development. The increase of the failure frequency for this system is expected. Additionally, it is difficult to maintain it for some discontinued boards of DFB and DFF and the older developing environment of software. Therefore, we are starting to study the new LLRF system of the next generation. In the present, we are exploring several possibilities of a new way and investigating each advantage and disadvantage. The project and the status of the development for the new system in the J-PARC linac LLRF are introduced.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO111
About •	paper received ※ 22 September 2018 paper accepted ※ 09 November 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPO115	CEBAF Photo Gun RF System	operation, laser, gun, LLRF	236
	T. E. Plawski, R. Bachimanchi, M. Diaz, H. Higgins, C. Hovater, C.I. Mounts, D.J. Seidman JLab, Newport News, Virgina, USA
	Funding: Authored by JSA, LLC under U.S. DOE Contract DE-AC05- 06OR23177 and DE-SC0005264. During the CEBAF 12 GeV Upgrade at Jefferson Lab, a fourth experimental hall, ’D’, was added to the existing three halls. To produce four beams and deliver them to all halls concurrently requires new frequencies and a new timing pattern of the electron bunches. Since a photo-gun is used to produce electron bunches, the gun’s drive laser pulses need to be synchronized with the required bunch rate frequencies of 499 MHz or 249.5 MHz. To meet these new operational requirements, the new LLRF system has been proposed. Very specific requirements (dual frequency operation) on one side and the simple RF drive mode operation on the other imply the use of a commercial off-the-shelf digital platform rather than a system typical for RF cavity field control. We have chosen the Texas Instruments FPGA board along with a high-speed 8-Channel, 14-Bit board, and a 4-Channel, 16-Bit board. The DAC board includes the clock generator for clocking ADCs, DACs and the FPGA. The complete Gun Laser LLRF system has been designed, built, and recently commissioned in the CEBAF Injector. This paper will detail the design and report on commissioning activities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO115
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPO007	FRIB Fast Machine Protection System: Chopper Monitor System Design	controls, machine-protect, high-voltage, power-supply	336
	Z. Li, D. Chabot, S. Cogan, S.M. Lidia, R.C. Webber FRIB, East Lansing, USA
	Funding: Work supported by Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661. The Facility for Rare Isotope Beams tunes the beam power from 0 to 400KW by chopping the beam current with a beam chopper in the Low Energy Beam Transport. A chopper monitoring system is employed to verify proper chopper operation to avoid delivery of undesired high-powered beam and to inhibit beam for machine protection purposes. The system monitors the incoming beam gate time structure, the chopper switch high voltage pulses, the chopper electrode charge/discharge currents, and the status of machine protection system. It is designed to switch off the beam within tens of nanoseconds of a detected fault. Chal-lenges include a dynamic beam gate pulse structure with pulse lengths as short as 0.6 µs and high voltage power supply current pulses of ~25 ns. A high speed "integrate and hold circuit with reset", Field Program-mable Gate Array based digital control circuit and high speed ADC circuit were developed to fulfil the re-quired functions. Design approach, simulation, and test results with the beam are the focus of this paper.
	Slides TUPO007 [1.082 MB]
	Poster TUPO007 [1.321 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO007
About •	paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPO132	Implementation of the Beam Loading Compensation Algorithm in the LLRF System of the European XFEL	LLRF, controls, cavity, FEL	594
	Ł. Butkowski, J. Branlard, M. Omet, R. Rybaniec, H. Schlarb, Ch. Schmidt DESY, Hamburg, Germany
	In the European XFEL, a maximum number of 2700 electron bunches per RF pulse with beam currents up to 4.5mA can be accelerated. Such large beam currents can cause a significant drop of the accelerating gradients, which results in large energy changes across the macro-pulse. But, the electron bunch energies should not deviate from the nominal energy to guarantee stable and reproducible generation of photon pulses for the European XFEL users. To overcome this issue, the Low Level RF system (LLRF) compensates in real-time the beam perturbation using a Beam Loading Compensation algorithm (BLC) minimizing the transient gradient variations. The algorithm takes the charge information obtained from beam diagnostic systems e.g. Beam Position Monitors (BPM) and information from the timing system. The BLC is a part of the LLRF controller implemented in the FPGA. The article presents the implementation of the algorithm in the FPGA and shows the results achieved with the BLC in the European XFEL.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO132
About •	paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPO041

Performance Test Results of Magnet Power Supply

controls, interface, power-supply, experiment

118

K.-H. Park, J.H. Han, S.-H. Jeong, Y.G. Jung, D.E. Kim, M.J. Kim, H.-G. Lee, S.B. Lee, B.G. Oh, H.S. Suh
PAL, Pohang, Kyungbuk, Republic of Korea

A high stable magnet power supply (MPS) was developed, which was a bipolar type with 200A of the output current at the 40V of output voltage. The MPS has been implemented by the digital signal processing technology using the DSP, FPGA, ADCs and so on. The output current stability of the MPS showed about 6ppm peak-to-peak in a short term experiment at 200A of its full output current. The long term stability was shown in 15 ppm peak-to-peak for 10 hours at 200A. And the others experimental results about the MPS were shown in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO041

About •

paper received ※ 31 August 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

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

MOPO107

Performance Evaluation of the RF Reference Phase Stabilization System on Fiber-optical Link for KEK e⁻/e⁺ Injector LINAC

feedback, linac, controls, EPICS

230

N. Liu, B. Du
Sokendai - Hayama, Hayama, Japan
D.A. Arakawa, H. Katagiri, T. Matsumoto, S. Michizono, T. Miura, F. Qiu, Y. Yano
KEK, Ibaraki, Japan
T. Matsumoto, T. Miura, F. Qiu
Sokendai, Ibaraki, Japan

KEK e⁻/e⁺ injector is the 600 m J-shaped LINAC which has 8 RF sectors. Stabilization of RF phase reference for long distance transmission is necessary for stable RF operation. In the present system, single-mode fiber-optical links without feedback control are used from sector 2 to 5. For the SuperKEKB, the phase stability requirement is within 0.1 deg. rms. The more stable RF phase reference is necessary to improve the phase stability. In this paper, a feedback control system for RF reference phase stabilization is tested for system performance evaluation. The temperature and humidity characteristics of the electric and optical components and phase stabilized optical fiber (PSOF) with different wavelengths will also be presented.

Poster MOPO107 [2.026 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO107

About •

paper received ※ 12 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019

Export •

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

MOPO111

Development of New LLRF System at the J-PARC Linac

LLRF, linac, low-level-rf, feedback

233

K. Futatsukawa, Z. Fang, Y. Fukui
KEK, Ibaraki, Japan
Y. Sato
Nippon Advanced Technology Co., Ltd., Tokai, Japan
S. Shinozaki
JAEA/J-PARC, Tokai-mura, Japan

In the J-PARC linac, the LLRF system with the digital feedback (DFB) and the digital feedforward (DFF) was adopted for satisfying requirement of amplitude and phase stabilities. It has been operated without serious problems. However, it has been used since the beginning of the J-PARC and more than ten years have already passed since the development. The increase of the failure frequency for this system is expected. Additionally, it is difficult to maintain it for some discontinued boards of DFB and DFF and the older developing environment of software. Therefore, we are starting to study the new LLRF system of the next generation. In the present, we are exploring several possibilities of a new way and investigating each advantage and disadvantage. The project and the status of the development for the new system in the J-PARC linac LLRF are introduced.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO111

About •

paper received ※ 22 September 2018 paper accepted ※ 09 November 2018 issue date ※ 18 January 2019

Export •

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

MOPO115

CEBAF Photo Gun RF System

operation, laser, gun, LLRF

236

T. E. Plawski, R. Bachimanchi, M. Diaz, H. Higgins, C. Hovater, C.I. Mounts, D.J. Seidman
JLab, Newport News, Virgina, USA

Funding: Authored by JSA, LLC under U.S. DOE Contract DE-AC05- 06OR23177 and DE-SC0005264.
During the CEBAF 12 GeV Upgrade at Jefferson Lab, a fourth experimental hall, ’D’, was added to the existing three halls. To produce four beams and deliver them to all halls concurrently requires new frequencies and a new timing pattern of the electron bunches. Since a photo-gun is used to produce electron bunches, the gun’s drive laser pulses need to be synchronized with the required bunch rate frequencies of 499 MHz or 249.5 MHz. To meet these new operational requirements, the new LLRF system has been proposed. Very specific requirements (dual frequency operation) on one side and the simple RF drive mode operation on the other imply the use of a commercial off-the-shelf digital platform rather than a system typical for RF cavity field control. We have chosen the Texas Instruments FPGA board along with a high-speed 8-Channel, 14-Bit board, and a 4-Channel, 16-Bit board. The DAC board includes the clock generator for clocking ADCs, DACs and the FPGA. The complete Gun Laser LLRF system has been designed, built, and recently commissioned in the CEBAF Injector. This paper will detail the design and report on commissioning activities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO115

About •

paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO007

FRIB Fast Machine Protection System: Chopper Monitor System Design

controls, machine-protect, high-voltage, power-supply

336

Z. Li, D. Chabot, S. Cogan, S.M. Lidia, R.C. Webber
FRIB, East Lansing, USA

Funding: Work supported by Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
The Facility for Rare Isotope Beams tunes the beam power from 0 to 400KW by chopping the beam current with a beam chopper in the Low Energy Beam Transport. A chopper monitoring system is employed to verify proper chopper operation to avoid delivery of undesired high-powered beam and to inhibit beam for machine protection purposes. The system monitors the incoming beam gate time structure, the chopper switch high voltage pulses, the chopper electrode charge/discharge currents, and the status of machine protection system. It is designed to switch off the beam within tens of nanoseconds of a detected fault. Chal-lenges include a dynamic beam gate pulse structure with pulse lengths as short as 0.6 µs and high voltage power supply current pulses of ~25 ns. A high speed "integrate and hold circuit with reset", Field Program-mable Gate Array based digital control circuit and high speed ADC circuit were developed to fulfil the re-quired functions. Design approach, simulation, and test results with the beam are the focus of this paper.

Slides TUPO007 [1.082 MB]

Poster TUPO007 [1.321 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO007

About •

paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO132

Implementation of the Beam Loading Compensation Algorithm in the LLRF System of the European XFEL

LLRF, controls, cavity, FEL

594

Ł. Butkowski, J. Branlard, M. Omet, R. Rybaniec, H. Schlarb, Ch. Schmidt
DESY, Hamburg, Germany

In the European XFEL, a maximum number of 2700 electron bunches per RF pulse with beam currents up to 4.5mA can be accelerated. Such large beam currents can cause a significant drop of the accelerating gradients, which results in large energy changes across the macro-pulse. But, the electron bunch energies should not deviate from the nominal energy to guarantee stable and reproducible generation of photon pulses for the European XFEL users. To overcome this issue, the Low Level RF system (LLRF) compensates in real-time the beam perturbation using a Beam Loading Compensation algorithm (BLC) minimizing the transient gradient variations. The algorithm takes the charge information obtained from beam diagnostic systems e.g. Beam Position Monitors (BPM) and information from the timing system. The BLC is a part of the LLRF controller implemented in the FPGA. The article presents the implementation of the algorithm in the FPGA and shows the results achieved with the BLC in the European XFEL.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO132

About •

paper received ※ 11 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

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