A5086466062- Gyrotron and Vacuum Electronics Research
- Particle accelerators and beam dynamics
- Magnetic confinement fusion research
- Microwave Engineering and Waveguides
- Superconducting Materials and Applications
- Particle Accelerators and Free-Electron Lasers
- Pulsed Power Technology Applications
- Plasma Diagnostics and Applications
- Electromagnetic Simulation and Numerical Methods
- Acoustic Wave Resonator Technologies
- Muon and positron interactions and applications
- Induction Heating and Inverter Technology
- Superconducting and THz Device Technology
- Fusion materials and technologies
- Ionosphere and magnetosphere dynamics
- Plasma Applications and Diagnostics
- Laser Design and Applications
- Photonic and Optical Devices
- Magnetic and Electromagnetic Effects
- Laser-Plasma Interactions and Diagnostics
- Astronomical Observations and Instrumentation
- Electromagnetic Compatibility and Measurements
- Inorganic Fluorides and Related Compounds
- Terahertz technology and applications
- Energy Harvesting in Wireless Networks
Karlsruhe Institute of Technology
2015-2024
Polytechnic University of Turin
2023
National Agency for New Technologies, Energy and Sustainable Economic Development
2022
University of Padua
2022
Institute of Plasma Physics
2019
National Research Council
2019
Max Planck Society
2012-2018
Institute of Technology of Cambodia
2012
Institute of Applied Physics
2011
FIZ Karlsruhe – Leibniz Institute for Information Infrastructure
1999-2010
A 2-MW continuous-wave (CW) 170-GHz coaxial-cavity gyrotron for electron cyclotron heating and current drive in the International Thermonuclear Experimental Reactor (ITER) is under development within European Gyrotron Consortium (EGYC1), a cooperation between research institutions. To support of industrial prototype CW gyrotron, short-pulse tube (preprototype) used at KIT Karlsruhe (former FZK) experimental verification design critical components, like gun, beam tunnel, cavity, quasi-optical...
The European DEMO is a pulsed device with pulse length of 2 hours. functions devoted to the heating and current drive system are: plasma breakdown, ramp-up flat-top where fusion reactions occur, control during phase, finally ramp-down. EU-DEMO project was in Pre-Concept Design Phase 2014-2020, meaning that some cases, design values precise requirements from physics point view were not yet frozen. A total 130 MW considered for all phases plasma: flat top, 30 required neoclassical tearing...
The feasibility of manufacturing a 2-MW CW coaxial cavity gyrotron at 170 GHz has been demonstrated and data required for fabrication an industrial tube have obtained. An engineering design prototype started recently with the goal to provide gyrotrons microwave output power International Thermonuclear Experimental Reactor (ITER). critical components as electron gun, RF system will be verified under realistic conditions short pulses using experimental Forschungszentrum Karlsruhe.
The development of high-power gyrotrons (118 GHz, 140 GHz) in continuous-wave (CW) operation for heating nuclear fusion plasmas has been progress several years a joint collaboration between different European research institutes and industrial partners. 140-GHz gyrotron being under the installation at W7-X stellarator now construction IPP Greifswald, Germany, operates TE/sub 28,8/ mode is equipped with diode type magnetron injection electron gun, an improved beam tunnel, high mode-purity...
The first series tube of the gyrotrons for 10-MW electron cyclotron resonance heating system stellarator W7-X was tested at Forschungszentrum Karlsruhe (FZK) and yielded a total output power 0.98 MW, with an efficiency 31% (without single-stage depressed collector) in short-pulse operation 0.92 MW pulses 180 s (efficiency almost 45% depression voltage 29 kV). Gaussian mode 0.91 MW. pulselength full (1 MW) is limited FZK by available supply. At reduced beam current, it possible to operate...
Megawatt gyrotrons are found to suffer from various parasitic oscillations, in particular, RF oscillations the beam tunnel prior desired interaction zone (the cavity). This paper describes experimental results a gyrotron experiment which was dedicated investigate and verify improved beam-tunnel structures. A system for spectral measurements new analysis method presented. The theoretical predictions on effect validate corresponding structure. In addition, other types of were observed explained.
The European Union is working toward providing 2-MW, coaxial-cavity, continuous-wave (cw) 170-GHz gyrotrons for ITER. Their design based on results from an experimental preprototype tube having a pulse length of several milliseconds, in operation at Forschungszentrum Karlsruhe (FZK) years now. first industrial prototype was designed cw but, phase, aimed 1 s the Gyrotron Test Facility Lausanne, Switzerland, as part phased testing/development program (1 s, 60 cw). this gyrotron are reported...
A key parameter for the gyrotron operation and efficiency is presence of trapped electrons. Two electron trapping mechanisms can take place in gyrotrons: (i) adiabatic trap (ii) magnetic potential well. Their influence on analyzed. gun design criteria are then proposed to suppress both order minimize risk possible problems. Experimental results three high power gyrotrons presented their performance correlated populations Finally, some very general principles limitation harmful trapping.
The multistage depressed collector (MDC) is essential to significantly increase the overall efficiency of gyrotron. To date, a short pulse (SP) MDC prototype system has been manufactured and currently under test. long-term goal that makes most sense use MDCs on 2-MW fusion gyrotrons in continuous wave (CW) operation. achieve this, CW based same physical principle as SP designed analyzed for first time. highlights this design are sweeping systems keep thermal loading within an acceptable...
Europe is devoting significant joint efforts to develop and manufacture MW-level gyrotrons for electron cyclotron heating current drive of future plasma experiments. The two most important ones are the stellarator Wendelstein W7-X at Greifswald Tokamak ITER Cadarache. While series production 140 GHz, 1 MW, CW 10-MW resonance system proceeding, European GYrotron Consortium presently developing EU-1 170 gyrotron ITER. initial design had already been initiated in 2007, as a risk mitigation...
An inverse magnetron injection gun (MIG) has been designed for the 2-MW, 170-GHz, coaxial-cavity gyrotron built at Karlsruhe Institute of Technology. The design could offer possibility implementation a larger emitter ring without need bigger bore hole in magnet compared with conventional type MIGs. Considering fundamental beam parameters, an excellent quality achieved numerical simulation. Electron-trapping suppression criteria were considered during phase MIG.
Abstract The European DEMO (EU-DEMO) reactor studies within EUROfusion aim to develop a fusion power plant concept. large tokamak device needs an auxiliary heating which, at the present stage, is provided by Electron Cyclotron (EC) system with up 130 MW foreseen reach different regions of plasma for heating, suppression instabilities and possibility support ramp-up ramp-down phases. conceptual design based on 2 coaxial-cavity gyrotron sources, transmission line (TL) using both circular...
High frequency (>230 GHz) megawatt-class gyrotrons are planned as RF sources for electron cyclotron resonance heating and current drive in DEMOnstration fusion power plants (DEMOs). In this paper, the first time, a feasibility study of 236 GHz DEMO gyrotron is presented by considering all relevant design goals possible technical limitations. A mode-selection procedure proposed order to satisfy multi-frequency frequency-step tunability requirements. An effective systematic approach...
A sensitivity analysis of manufacturing imperfections and possible misalignments the emitter ring in gyrotron cathode structure on electron beam quality has been performed. It shown that a radial displacement order few tens microns can cause dramatic effects therefore operation. Two different design approaches are proposed to achieve an which is less sensitive imperfections.
Karlsruhe Institute of Technology (KIT) is doing research and development in the field megawatt-class radio frequency (RF) sources (gyrotrons) for Electron Cyclotron Resonance Heating (ECRH) systems International Thermonuclear Experimental Reactor (ITER) DEMOnstration Fusion Power Plant that will follow ITER. In focus verification European coaxial-cavity gyrotron technology which shall lead to gyrotrons operating at an RF output power significantly larger than 1 MW CW above 200 GHz. A major...
The requirement of higher efficiency in high power microwave devices, such as traveling wave tubes and gyrotrons, guides scientific research to more advanced types collector systems. First, a conceptual design approach multistage depressed for sheet electron beam confined by magnetic field is presented. sorting the trajectories, according their initial kinetic energy, based on E × B drift concept. optimization geometrical parameters analytical equations under several general assumptions....
In the first part of this paper, status 140-GHz continuously operated gyrotrons with an output power 1 MW for stellarator Wendelstein 7-X will be described. With series tube, 1000 kW has been achieved in short pulse operation (milliseconds) electron beam current 40 A, and 1150 at 50 A. a length 3 min limited by available high-voltage (HV) supply, 920 about A efficiency 45% mode purity 97.5% obtained. At reduced 29 570 was measured 1893 s without significant increase tube pressure. The energy...
High-power, high-frequency gyrotrons for electron cyclotron resonance heating and current drive, such as proposed the demonstration thermonuclear fusion reactor DEMO, require operating modes of very high order. As it is shown, selection can be based on multi-frequency operability. A general strategy derived, suitable multi-purpose with quasi-optical mode converter single-disc output window. Two examples, one them relevant future DEMO gyrotron designs, are discussed.
The European 1-MW, 170-GHz continuous wave industrial prototype gyrotron for electron cyclotron resonance heating and current drive on international thermonuclear experimental reactor was during 2016 under test at the Karlsruhe Institute of Technology (KIT) facility. In order to optimize operation, tube first thoroughly tested in short-pulse regime, with pulses that did not exceed 10 ms, a wide range operational parameters. Then, after proper conditioning tube, operation extended longer...