uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
A new high-power low-loss air-dielectric stripline Gysel divider/combiner for particle accelerator applications at 352 MHz
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, FREIA. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
Vietnam National University (VNU), Hanoi, Vietnam.
Vietnam National University (VNU), Hanoi, Vietnam.
Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, FREIA. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
Show others and affiliations
2018 (English)In: IET Control Theory & Applications, ISSN 1751-8644, E-ISSN 1751-8652, no 5, p. 264-267Article in journal (Refereed) Published
Abstract [en]

This study presents a new two-way Gysel combiner based on an air-dielectric stripline which allows to handle very high radio-frequency power levels with low-loss suitable for power combination in accelerator applications. The insertion loss of the combiner is 0.1 dB (2%). A thick stripline implementation allows improving the power capability in both continuous wave (CW) and pulsed operation. In addition, a mechanical tuner allows compensating for assembly and fabrication discrepancies. A methodology of designing the Gysel combiner as well as high-power measurements up to 22 kW in pulsed mode are presented. Simulations and measurements are in very good agreement.

Place, publisher, year, edition, pages
2018. no 5, p. 264-267
National Category
Other Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
URN: urn:nbn:se:uu:diva-334913DOI: 10.1049/joe.2017.0793ISI: 000436345200003OAI: oai:DiVA.org:uu-334913DiVA, id: diva2:1161140
Projects
ESSAvailable from: 2017-11-29 Created: 2017-11-29 Last updated: 2019-11-21Bibliographically approved
In thesis
1. High Power Radio Frequency Solid-State Amplifiers and Combiners for Particle Accelerators: From module to system design approach
Open this publication in new window or tab >>High Power Radio Frequency Solid-State Amplifiers and Combiners for Particle Accelerators: From module to system design approach
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The rise of Big Science projects brings issues related to the energy consumption and the associated environmental impacts of such large-scale facilities. Therefore, environmentally-sustainable developments are undertaken towards the adoption of energy savings and improved energy-efficient approaches. The advent of the superconducting (SC) radio frequency (RF) accelerating cavity is bringing answers to these issues. Such superconducting RF (SRF) cavity is made of niobium that allows much higher accelerating gradients with a minimization of the energy consumption. The SC RF technology is increasingly used in many modern particle accelerators, including: the European Spallation Source (ESS), the X-ray Free Electron Laser (XFEL), the Linac Coherent Light Source (LCLS)-II and the proposed International Linear Collider (ILC).

The innovation of solid state PA technology pushes limits regarding packaging, efficiency, frequency capability, thermal stability, making them more attractive than other well-established alternative technologies, such as vacuum tube technology in mid-range power applications. Through the investigations of designs and techniques, this research goal of the thesis allows to improve solid-state based power generation systems from module to the overall system design. This thesis introduces the single-ended PA design approach in planar technology and at kilowatt level. The design solution unlocks different possibilities including: improved integration, layout flexibility for tuning, and suitably for mass productions that are demanded in future high peak power generation systems. The novel amplifier design is followed by time domain characterization to fully evaluate the pulse profiles of such amplifiers when delivering kilowatt output power level for operation in conjunction with SRF accelerating cavities. Amplitude and phase stability of those amplifiers are also investigated in time-domain. The extracted data can then be used as measurement-based model for predicting factors which could degrade the overall stability of the associated PA.

Future RF power generation systems built around solid state PAs need also efficient combining strategies. Two engineering design solutions are investigated in this thesis aiming for mid- and high- range power combination. One solution is based on a combination of the Gysel structure using suspended strip-line technology for improved power handling capability. Another solution is implementing a radial combiner, which uses re-entrant cavity resonator at 352 MHz and door-nob geometry for coupling at inputs and at the output. These solutions facilitate the scaling up 400 kW for powering ESS spoke cavities while maintaining a high degree of efficiency in RF power generation. This thesis gives insights of system integration and tuning procedures with a demonstration of combining 8 modules, delivering a total of 10 kW output power. Along with the proposed combining solutions at higher power levels, the nominal power block of 10 kW is used as an elementary block to propose scaling up in power till the 400 kW nominal power required by ESS.

Finally, this thesis focuses on implementing an optimal charging scheme for SRF cavities, which helps reducing the wasted energy and improves the overall efficiency operation at future accelerating facilities. Therefore, these results contribute further to the larger adoption of solid state technologies in the future power generation systems for particle accelerators.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2019. p. 98
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1881
Keywords
solid state technology, power amplifier, superconducting cavities, optimal charging, high efficiency, particle accelerators
National Category
Engineering and Technology
Research subject
Engineering Science with specialization in Microwave Technology
Identifiers
urn:nbn:se:uu:diva-397500 (URN)978-91-513-0818-0 (ISBN)
Public defence
2020-01-15, Häggsalen, Ångströmlaboratoriet, Lägerhyddsvägen 1, Uppsala, 09:15 (English)
Opponent
Supervisors
Available from: 2019-12-20 Created: 2019-11-21 Last updated: 2020-01-13

Open Access in DiVA

fulltext(683 kB)380 downloads
File information
File name FULLTEXT02.pdfFile size 683 kBChecksum SHA-512
fb13ac37f4dcec9d1b4d4d5c5bd3824eb662d717a6e273fc849f1cd8cd1b06f47a4e1a8ecb9a3a89a5605caa3b6dede58b534ef2ab1b7e054072fdd396ae5187
Type fulltextMimetype application/pdf

Other links

Publisher's full textFörlagets fulltext

Authority records BETA

Hoang Duc, LongJobs, MagnusRuber, RogerDancila, Dragos

Search in DiVA

By author/editor
Hoang Duc, LongJobs, MagnusRuber, RogerDancila, Dragos
By organisation
FREIASolid State ElectronicsHigh Energy Physics
In the same journal
IET Control Theory & Applications
Other Electrical Engineering, Electronic Engineering, Information Engineering

Search outside of DiVA

GoogleGoogle Scholar
Total: 380 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 448 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf