A5006713428- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Fusion materials and technologies
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Plasma Diagnostics and Applications
- Laser-Plasma Interactions and Diagnostics
- Nuclear reactor physics and engineering
- Energy Efficient Wireless Sensor Networks
- Energy Harvesting in Wireless Networks
- Innovative Energy Harvesting Technologies
- Atomic and Subatomic Physics Research
- Indoor and Outdoor Localization Technologies
- Underwater Vehicles and Communication Systems
- Gyrotron and Vacuum Electronics Research
- Laser-induced spectroscopy and plasma
- Iterative Learning Control Systems
- Physics of Superconductivity and Magnetism
- Acoustic Wave Resonator Technologies
- Power Line Inspection Robots
- Distributed systems and fault tolerance
- Wireless Power Transfer Systems
- Water Quality Monitoring Technologies
- Advanced Battery Technologies Research
- Advanced MEMS and NEMS Technologies
École Polytechnique Fédérale de Lausanne
2015-2025
Massachusetts Institute of Technology
2019
Dutch Institute for Fundamental Energy Research
2019
University of York
2019
Culham Science Centre
2019
Institute of Plasma Physics
2011-2017
Max Planck Society
2015-2016
Max Planck Institute for Plasma Physics
2015-2016
National Agency for New Technologies, Energy and Sustainable Economic Development
2012-2014
Politecnico di Milano
2006-2013
Abstract Nuclear fusion using magnetic confinement, in particular the tokamak configuration, is a promising path towards sustainable energy. A core challenge to shape and maintain high-temperature plasma within vessel. This requires high-dimensional, high-frequency, closed-loop control actuator coils, further complicated by diverse requirements across wide range of configurations. In this work, we introduce previously undescribed architecture for controller design that autonomously learns...
The success of wireless sensor networks and their pervasive use is somehow constrained by energy supply which, generally provided batteries, a finite resource. Energy harvesting mechanisms must hence be taken into account to grant long time operational life, with solar being the most interesting one in outdoor deployments due its relatively high power density. In this paper we propose <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">low-power</i>...
The paper proposes an environmental monitoring framework based on a wireless sensor network technology characterized by energy harvesting, robustness with respect to large class of perturbations and real-time adaptation the topology. fully designed developed ad hoc system, clusters relying star topology, encompasses sensing activity, one-step local transmission from nodes gateway, remote data gateway control center, storage in DB visualization. Hw Sw modules have been either carefully...
This work presents a novel, real-time capable, 10-channel Multispectral Advanced Narrowband Tokamak Imaging System installed on the TCV tokamak, MANTIS. Software and hardware requirements are presented together with complete system architecture. The image quality of is assessed emphasis effects resulting from narrowband interference filters. Some filters found to create internal reflection images that correlated filters' coefficient. was measured for selected where significant absorption (up...
Abstract In magnetic confinement thermonuclear fusion the exhaust of heat and particles from core remains a major challenge. Heat leaving are transported via open field lines to region reactor wall, called divertor. Unabated, particle fluxes may become intolerable damage Controlled ‘plasma detachment’, regime characterized by both large reduction in plasma pressure temperature at divertor target, is required reduce onto Here we report systematic approach towards achieving this critical need...
Energy conservation techniques for sensor networks typically rely on the assumption that data sensing and processing consume considerable less energy than communication. This does not hold in some practical application scenarios, where ad hoc developed units require power consumption comparable with, or even larger than, of radio. In this paper we focus an embedded monitoring snow composition mountain slopes avalanche forecasting. To lower propose adaptive sampling algorithm able to...
The TCV tokamak is augmenting its unique historical capabilities (strong shaping, strong electron heating) with ion heating, additional heating compatible high densities, and variable divertor geometry, in a multifaceted upgrade program designed to broaden operational range without sacrificing fundamental flexibility. rooted three-pronged approach aimed at ITER support, explorations towards DEMO, research. A 1 MW, tangential neutral beam injector (NBI) was recently installed promptly...
Reinforcement learning (RL) has shown promising results for real-time control systems, including the domain of plasma magnetic control. However, there are still significant drawbacks compared to traditional feedback approaches confinement. In this work, we address key RL method; achieving higher accuracy desired properties, reducing steady-state error, and decreasing required time learn new tasks. We build on top Degrave et al. (2022), present algorithmic improvements agent architecture...
The rampdown in tokamak operations is a difficult to simulate phase during which the plasma often pushed towards multiple instability limits. To address this challenge, and reduce risk of disrupting operations, we leverage recent advances Scientific Machine Learning (SciML) develop neural state-space model (NSSM) that predicts dynamics Tokamak \`a Configuration Variable (TCV) rampdowns. By integrating simple physics structure data-driven models, NSSM efficiently learns from modest dataset...
<title>Abstract</title> The rampdown in tokamak operations is a difficult to simulate phase during which the plasma often pushed towards multiple instability limits. To address this challenge, and reduce risk of disrupting operations, we leverage recent advances Scientific Machine Learning (SciML) develop neural state-space model (NSSM) that predicts dynamics Tokamak à Configuration Variable (TCV) rampdowns. By integrating simple physics structure data-driven models, NSSM efficiently learns...
Routine reaction to approaching disruptions in tokamaks is currently largely limited machine protection by mitigating an ongoing disruption, which remains a basic requirement for ITER and DEMO [1]. Nevertheless, mitigated disruption still generates stress the device. Additionally, future fusion devices, high-performance discharge time itself will be very valuable. Instead of reacting only on generic features, occurring shortly before ultimate goal actively avoid at early stage, sustain...
Since the 2012 IAEA-FEC Conference, FTU operations have been largely devoted to runaway electrons generation and control, exploitation of 140 GHz electron cyclotron (EC) system liquid metal limiter elements. Experiments on shown that measured threshold electric field for their is larger than predicted by collisional theory can be justified considering synchrotron radiation losses. A new control algorithm was developed tested in presence a current plateau, allowing minimize interactions with...
The successful performance of a model predictive profile controller is demonstrated in simulations and experiments on the TCV tokamak, employing test environment. Stable high-performance tokamak operation hybrid advanced plasma scenarios requires control over safety factor (q-profile) kinetic parameters such as beta. This demands to establish reliable routines presently operational tokamaks.
Post-disruption runaway electron (RE) beams in tokamaks with large current can cause deep melting of the vessel and are one major concerns for ITER operations. Consequently, a considerable effort is provided by scientific community order to test RE mitigation strategies. We present an overview results obtained at FTU TCV controlling position improve safety repeatability studies such as massive gas (MGI) shattered pellet injections (SPI). show that proposed beam controller (REB-C) implemented...
On the FTU tokamak, collective Thomson scattering (CTS) diagnostic was renewed for investigating possible excitation of parametric decay instabilities (PDI) by electron cyclotron (EC) or CTS probe beams in presence magnetic islands and measure their effects on EC power absorption.
This work reports developments of the incoherent TS diagnostic capabilities in Tokamak à Configuration Variable (TCV). Their goals are to (i) diagnose TCV divertor region, and (ii) provide Te ne profiles plasma bulk real-time. These two new implemented within framework a upgrade that will insert baffles lower region. 20 spectrometers being installed access electron temperatures down ~1 eV, for densities above ~1.5×1019m−3 They measure Thomson light scattered along vertical propagation path...
Elongated plasmas lead to improved performance in tokamaks but make the plasma prone vertical instability, which requires active feedback control, a critical issue for future fusion reactors. Vertical control was optimized TCV tokamak by applying modern theory electromagnetic models plasma-vessel-coils dynamics. Two different optimal combinations of poloidal field coils actuation are derived from linear response and used on timescales controlling position. On fast timescales, priority is...
Rock face collapses are one of the most dangerous and sudden natural risks in mountain environments. Traditional investigation techniques (e.g., strain gauge, inclinometer) cannot guarantee neither a non-invasive monitoring within rocks nor prompt alarm case possible collapse. Real-time systems, which might provide an effective evaluation dynamics phenomenon for subsequent forecasting phase, generally rely on wired solutions that unfeasible environmental applications. In this paper, we...
Kinetic equilibrium reconstruction (KER) in tokamaks is the solution of free-boundary MHD that best fits external magnetic measurements and internal plasma profiles as imposed from modeling and/or available measurements. In this paper, for first time, KER has been performed real-time by coupling code LIUQE to 1.5D transport RAPTOR, during a TCV discharge. The used dynamic state observer evolving current diffusion equation, electron heat particle equations correcting prediction with...
Abstract Plasma start-up is typically achieved manipulating poloidal magnetic fields, gas injection and possibly auxiliary heating. Model-based design techniques have been gaining increasing attention in view of future large tokamaks which more stringent constraints less room for trial-and-error. In this paper, we formulate the tokamak scenario problem as a constrained optimization introduce novel shot-to-shot correction algorithm, based on Iterative Learning Control concept, to compensate...
This paper investigates a power management architecture based on hybrid accumulator system that utilizes the supercapacitor cell as storage element for energy harvesting applications. The guarantees longer lifetime in terms of charge cycles, it presents itself ¿green¿ technology compared to batteries and has wide range operating temperature. drawbacks this type solution are low density leakage current reduce performance very In photovoltaic scavenger supercapacitors is investigated can work...
A novel plasma position and shape controller has been developed for the highly flexible shaping poloidal-field coil set of TCV tokamak, to aid in precise control advanced configurations such as negative-triangularity plasmas, snowflake super-X divertors, doublets. This work follows relies on deployment a new, sub-ms, real-time magnetic equilibrium-reconstruction algorithm. The formulation ensures flexibility through an ordering controlled variables from most easily least controlled, while...