A5034061807- Magnetic confinement fusion research
- Fusion materials and technologies
- Superconducting Materials and Applications
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Nuclear reactor physics and engineering
- Laser-Plasma Interactions and Diagnostics
- Cardiovascular Function and Risk Factors
- Advanced Control Systems Optimization
- Metabolism and Genetic Disorders
- Scheduling and Optimization Algorithms
- Advanced Manufacturing and Logistics Optimization
- Nuclear Physics and Applications
- Optimization and Search Problems
- Viral Infections and Vectors
- Target Tracking and Data Fusion in Sensor Networks
Dutch Institute for Fundamental Energy Research
2021-2024
Eindhoven University of Technology
2021-2024
Max Planck Institute for Plasma Physics
2023
We present the first analysis of atomic and molecular processes at play during detachment in MAST-U Super-X divertor using spectroscopy data. Our indicates can be separated into four sequential phases: First, ionisation region detaches from target onset leaving a increased densities downstream. The plasma interacts with these molecules, resulting ions ($D_2^+$ and/or $D_2^- \rightarrow D + D^-$) that further react leading to Molecular Activated Recombination Dissociation (MAR MAD), which...
Future fusion reactors require a safe, steady-state divertor operation. With deep detachment, which is typically induced by impurity seeding, the radiation concentrates in small region at X-point or on closed flux surfaces above X-point. This so-called radiator (XPR) moves further inside confined with increasing seeding and location can be actively controlled. At AUG, parameter space for operation an XPR was significantly extended, using active feedback location. The observed nearly whole...
Abstract JET returned to deuterium-tritium operations in 2023 (DTE3 campaign), approximately two years after DTE2. DTE3 was designed as an extension of JET's 2022-2023 deuterium campaigns, which focused on developing scenarios for ITER and DEMO, integrating in-depth physics understanding control schemes. These were evaluated with mixed D-T fuel, using the only remaining tritium-capable tokamak until its closure 2023. A core-edge-SOL integrated H-mode scenario developed tested D-T, showing...
Abstract Within the 9th European Framework programme, since 2021 EUROfusion is operating five tokamaks under auspices of a single Task Force called ‘Tokamak Exploitation’. The goal to benefit from complementary capabilities each machine in coordinated way and help developing scientific output scalable future largre machines. programme this ensures that ASDEX Upgrade, MAST-U, TCV, WEST JET (since 2022) work together achieve objectives Missions 1 2 Roadmap: i) demonstrate plasma scenarios...
Estimation of the dynamic evolution electron plasma density during a tokamak discharge is crucial since it directly affects performance, confinement and stability. Therefore needs to be monitored controlled. Knowledge profile can also used control in more direct way desired aspects density, for example choosing core, volume averaged or edge replacing methods that rely e.g. on single line-averaged from specific interferometer chord. The reconstruction performed with RAPDENS code, employing...
DEMO will have a limited diagnostic set for optimization of reactor performance, and coverage due to challenging conditions. This poses challenges control, especially detachment control which is planned be performed with spectroscopic lines-of-sight. To demonstrate mitigation the problem, we implemented sparse sensor placement technique on TCV case spectroscopy. Experimental CIII 2D emissivity profiles from MANTIS multispectral imaging system at are used create synthetic spectroscopy system,...
Abstract The successful operation of fusion reactors requires plasma scenarios with good core confinement and acceptable first wall heat loads that are stable robust to external perturbations. This poses both physical technological challenges. One the technologies addresses these challenges is a complex feedback control system supports advances in understanding helps ensure operating conditions. marginally plasmas often leads off-normal events (such as disruptions) can prevent some extent....
Abstract Tokamak à configuration variable (TCV), recently celebrating 30 years of near-continual operation, continues in its missions to advance outstanding key physics and operational scenario issues for ITER the design future power plants such as DEMO. The main machine heating systems changes are first described. Then follow five sections: plasma scenarios. Base-Line (IBL) discharges, triangularity studies together with X3 N2 seeding. Edge localised mode suppression, a high radiation...
Model predictive control (MPC) is promising for fueling and core density feedback in nuclear fusion tokamaks, where the primary actuators, frozen hydrogen fuel pellets fired into plasma, are discrete. Previous approaches have only approximated pellet injection as a continuous input due to complexity that it introduces. In this letter, we model plasma hybrid system propose two MPC strategies control: mixed-integer (MI) using conventional programming (MIP) solver utilizing our novel...
Experiments in various tokamaks and their analysis identify the fast ions (FI) generated by NBI and/or ICRF heating as one of main causes observed improvement core confinement: can reduce microturbulence (mainly Ion-Temperature-Gradient (ITG) driven modes) either electrostatically or electromagnetically, they resonate with fishbones high-frequency Alfvén modes, which turn contribute stabilizing ITG.In this perspective, we discuss recent experiments done on ASDEX Upgrade (AUG) where is...
Plasma density is one of the key quantities that need to be controlled in real-time as it scales directly with fusion power and, if left uncontrolled, limits can reached leading a disruption. On ASDEX Upgrade (AUG), measurements are line-integrated density, measured by interferometers, and average derived from bremsstrahlung spectroscopy. For control, these used reconstruct radial profile using an extended Kalman filter (EKF). However, discharges where ion cyclotron resonance heating (ICRH)...
Abstract In contemporary magnetic confinement devices, the density distribution is sensed with interferometers and actuated feedback controlled gas injection open-loop pellet injection. This at variance control for ITER DEMO, that will depend mainly on as an actuator in feed-back control. paper presents recent developments state estimation of electron profile using relevant sensors actuators. As a first step, Thomson scattering included existing dynamic observer. Second, model predictive...
Pellets - mm-size solid bodies produced from frozen fuel – are mainly destined for fuelling purposes in the fusion reactor EU-DEMO. However, pellets have been proven capable tools further tasks too, e.g. ELM frequency control and efficient delivery of seeding gases already demonstrated. Here, a concept is presented single pellet launcher based on stop-cylinder centrifuge accelerator equipped with multiple sources. The sources can deliver different sizes composition, finally combined into one...
Abstract Control of heat exhaust is essential for the operation power producing fusion reactors. Here, we present results feedback control experiments in JET and AUG. In JET, demonstrate first X-point radiator (XPR) DD DT discharges using argon seeding. AUG, improve XPR with nitrogen seeding, resulting achieving detached L-H H-L transition (in a single discharge). The controllers are designed model-based design procedure. required models obtained experimentally perturbative (system...
Core particle fueling, an essential task in the European demonstration fusion power plant EU-DEMO, relies on adequate pellet injection. However, pellets are fragile objects, and their delivery efficiency can hardly be assumed to unity. Exploring kinetic control of EU-DEMO1 scenario indicates that such missed-out do cause a considerable problem for keeping burning plasma. Missed-out severe drop plasma density turn results potential drastic loss burn power. Efforts under way at ASDEX Upgrade...
On contemporary tokamaks, the control of density is mainly performed with gas injection or single type pellets (mm-sized body frozen fuel). future reactors, pellet expected to be main actuator available for core as foreseen ineffective. It anticipated that multiple types (e.g., varying size, velocity, composition) will used. Hence, a strategy can actuators required. This work presents model predictive controller (MPC) which regulate electron profile tokamak fusion plasma using injectors and...
Model predictive control (MPC) is promising for fueling and core density feedback in nuclear fusion tokamaks, where the primary actuators, frozen hydrogen fuel pellets fired into plasma, are discrete. Previous approaches have only approximated pellet injection as a continuous input due to complexity that it introduces. In this letter, we model plasma hybrid system propose two MPC strategies control: mixed-integer (MI) using conventional programming (MIP) solver utilizing our novel...
Abstract Pellet injection is regarded as the only realistic actuator for core density control in future reactors such ITER and DEMO. However, a strategy that can reliably regulate plasma close to operational limits using multiple pellet injectors not yet available. In this paper, we present first integrated model simulations where dedicated model-predictive controller included JINTRAC. We show that, when continuous actuators are considered, simple transport with steady-state disturbance...
We study the problem of scheduling jobs on parallel machines minimizing total completion time, with each job using exactly one resource. First, we derive fundamental properties and show that is polynomially solvable if $p_j = 1$. Then look at a variant shortest processing time rule as an approximation algorithm for it gives least $(2-\frac{1}{m})$-approximation. Subsequently, that, although complexity remains open, three related problems are $\mathcal{NP}$-hard. In first problem, every...
In contemporary magnetic confinement devices, the density distribution is sensed with interferometers and actuated feedback controlled gas injection open-loop pellet injection. This at variance control for ITER DEMO, that will depend mainly on as an actuator in feed-back control. paper presents recent developments state estimation of electron profile using relevant sensors actuators. As a first step, Thomson scattering included existing dynamic observer. Second, model predictive developed...