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Fusion Burn Regulation via Deuterium Tritium Mixture control in the Joint European Torus

PRX Energy 2025年第2期4卷 023007-023007页

作者： M. Lennholm L. Piron D. Valcarcel P. Almond M. Baruzzo M. van Berkel T. Bosman L. Ceelen P. Fox K. Kirov B. Kool C. Lowry J. Mitchell B. Sieglin H. Sun Plasma Science and Fusion Operations Directorate United Kingdom Atomic Energy Authority Culham Campus Abingdon Oxon OX14 3DB United Kingdom morten.lennholm@ukaea.uk Dipartimento di Fisica “G. Galilei” Università degli Studi di Padova Padova Italy Consorzio RFX Corso Stati Uniti 4 35127 Padova Italy Fusion and Nuclear Safety Department ENEA C.R. Frascati via E. Fermi 45 00044 Frascati Rome Italy DIFFER—Dutch Institute for Fundamental Energy Research De Zaale 20 5612 AJ Eindhoven The Netherlands Department of Mechanical Engineering Control Systems Technology Group Eindhoven University of Technology Eindhoven The Netherlands Max Planck Institute for Plasma Physics Boltzmannstr. 2 85748 Garching Germany

The first generation of nuclear fusion reactors is expected to operate using a mixture of deuterium (D) and tritium (T) fuel. controlling the D:T ratio is a promising option to control the fusion burn rate. The Joint European Torus (JET), as the only operational tokamak that can use tritium, is uniquely placed to test the feasibility of such control. Experiments carried out in 2023, during the third JET D-T campaign, have demonstrated effective feedback control of the D:T ratio under H-mode conditions. The D:T ratio was measured using visible spectroscopy and tritium was injected via gas valves, while deuterium was injected either via gas valves or pellets. In these experiments, the fusion power, measured via the neutron rate, responded promptly to variations in the measured D:T ratio. This demonstrates that, although the plasma is fueled mainly at the edge, rapid mixing of the isotopes occurs throughout the plasma and controlling the D:T ratio is an effective way of controlling the burn rate. To sustain a stable type-I ELMy H-mode plasma, it is desirable to maintain a given edge localised mode (ELM) frequency. However, both the total fueling rate and the D:T ratio influence this ELM frequency, with higher fueling rates and higher D:T ratios both resulting in more frequent ELMs. For this reason, the D:T ratio controller was combined with an ELM frequency controller in a multi-input multi-output controller. Successful simultaneous decoupled control of the D:T ratio and ELM frequency was demonstrated using a combination of pellet and gas fueling. This is the first and, for the time being, only demonstration of such an advanced burn control scheme in a DT plasma.

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Cooperative pollution source localization and cleanup with a bio-inspired swarm robot aggregation

arXiv

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arXiv 2019年

作者： Amjadi, Arash S. Raoufi, Mohsen Turgut, Ali E. Broughton, George Krajník, Toma7acute š Arvin, Farshad School of Electrical Engineering University of Tabriz Tabriz Iran Department of Aerospace Engineering Sharif University of Technology Tehran Iran Mechanical Engineering Department Middle East Technical University Ankara Turkey Artificial Intelligence Centre Faculty of Electrical Engineering Czech Technical University Prague Czech Republic Control Systems Group School of Electrical and Electronic Engineering University of Manchester ManchesterM13 9PL United Kingdom

Using robots for exploration of extreme and hazardous environments has the potential to significantly improve human safety. For example, robotic solutions can be deployed to find the source of a chemical leakage and clean the contaminated area. This paper demonstrates a proof-of-concept bio-inspired exploration method using swarm robotic system, which is based on a combination of two bio-inspired behaviors: aggregation, and pheromone tracking. The main idea of the work presented is to follow pheromone trails to find the source of a chemical leakage and then carry out a decontamination task by aggregating at the critical zone. Using experiments conducted by a simulated model of a Mona robot, we evaluate the effects of population size and robot speed on the ability of the swarm in a decontamination task. The results indicate feasibility of deploying robotic swarms in an exploration and cleaning task in an extreme environment. Copyright © 2019, The Authors. All rights reserved.

关键词： Population statistics

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Identifying position-dependent mechanical systems: A modal approach with applications to wafer stage control

arXiv

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arXiv 2018年

作者： Voorhoeve, Robbert De Rozario, Robin Aangenent, Wouter Oomen, Tom Eindhoven University of Technology Department of Mechanical Engineering Control Systems Technology group Eindhoven Netherlands ASML Research Mechatronics Veldhoven Netherlands

Increasingly stringent performance requirements for motion control necessitate the use of increasingly detailed models of the system behavior. Motion systems inherently move, therefore, spatio-temporal models of the flexible dynamics are essential. In this paper, a two-step approach for the identification of the spatio-temporal behavior of mechanical systems is developed and applied to a prototype industrial wafer stage with a lightweight design for fast and highly accurate positioning. The proposed approach exploits a modal modeling framework and combines recently developed powerful linear time invariant (LTI) identification tools with a spline-based mode-shape interpolation approach to estimate the spatial system behavior. The experimental results for the wafer stage application confirm the suitability of the proposed approach for the identification of complex position-dependent mechanical systems, and show the pivotal role of the obtained models for improved motion control performance. Copyright © 2018, The Authors. All rights reserved.

关键词： Interpolation

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Online learning with stability guarantees: A memory-based real-time model predictive controller∗

arXiv

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arXiv 2018年

作者： Schwenkel, Lukas Gharbi, Meriem Trimpe, Sebastian Ebenbauer, Christian Institute for Systems Theory and Automatic Control University of Stuttgart Germany Institute for Data Science in Mechanical Engineering RWTH Aachen University Germany Intelligent Control Systems Group Max Planck Institute for Intelligent Systems Stuttgart Germany

We propose and analyze a real-time model predictive control (MPC) scheme that utilizes stored data to improve its performance by learning the value function online with stability guarantees. For linear and nonlinear systems, a learning method is presented that makes use of basic analytic properties of the cost function and is proven to learn the MPC control law and the value function on the limit set of the closed-loop state trajectory. The main idea is to generate a smart warm start based on historical data that improves future data points and thus future warm starts. We show that these warm starts are asymptotically exact and converge to the solution of the MPC optimization problem. Thereby, the suboptimality of the applied control input resulting from the real-time requirements vanishes over time. Numerical show that existing real-time MPC schemes can be improved by storing optimizatising the proposed ng scheme. Copyright © 2018, The Authors. All rights reserved.

关键词： Model predictive control

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A novel frequency domain maximum likelihood approach for estimating transport coefficients in cylindrical geometry for nuclear fusion devices

A novel frequency domain maximum likelihood approach for est...

引用

IEEE Annual Conference on Decision and control

作者： Matthijs van Berkel Gerardus W. Oosterwegel Martijn Anthonissen Hans J. Zwart Gerd Vandersteen DIFFER-Dutch Institute for Fundamental Energy Research Energy Systems and Control group Eindhoven The Netherlands Dept. of Mathematics and Computer Science Eindhoven University of Technology Eindhoven The Netherlands Dept. of Mechanical Engineering Eindhoven University of Technology Eindhoven The Netherlands Dept. of Fundamental Electricity and Instrumentation Vrije Universiteit Brussel (VUB) Brussels Belgium

ISBN: (数字)9781728113982

ISBN: (纸本)9781728113999

This paper introduces a novel maximum likelihood approach to determine the local thermal transport coefficients belonging to diffusion and convection from excitation (perturbative) transport experiments. It extends previous work developed for linear (slab) geometry to cylindrical (toroidal) geometry for fusion reactors. The previous linear geometry approach is based on analytic solutions of the partial differential equation. However, for cylindrical geometries with convection the analytic solutions are confluent hypergeometric functions (CHFs) with complex valued arguments. Most numerical libraries do not support CHFs evaluation with complex valued arguments. Hence, this paper proposes the use of an ultra-fast transfer function evaluation based on sparse numerical solutions for the discretized partial differential equation. This solution is implemented in MATLAB and incorporated in the frequency domain Maximum Likelihood Estimation framework. Consequently, transport coefficients can be estimated consistently when measurements are perturbed by coloured and spatially correlated noise.

关键词： Fusion reactors Geometry Maximum likelihood estimation Temperature sensors Partial differential equations Frequency-domain analysis

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A whole-body model predictive control scheme including external contact forces and com height variations

arXiv

引用

arXiv 2018年

作者： Mirjalili, Reihaneh Yousefi-koma, Aghil Shirazi, Farzad A. Nikkhah, Arman Nazemi, Fatemeh Khadiv, Majid School of Mechanical Engineering College of Engineering University of Tehran Tehran Iran School of Mechanical Engineering College of Engineering University of Tehran Tehran Iran Movement Generation and Control group Max-Planck Institute for Intelligent Systems Tuebingen Germany

In this paper, we present an approach for generating a variety of whole-body motions for a humanoid robot. We extend the available Model Predictive control (MPC) approaches for walking on flat terrain to plan for both vertical motion of the Center of Mass (CoM) and external contact forces consistent with a given task. The optimization problem is comprised of three stages, i. e. the CoM vertical motion, joint angles and contact forces planning. The choice of external contact (e. g. hand contact with the object or environment) among all available locations and the appropriate time to reach and maintain a contact are all computed automatically within the algorithm. The presented algorithm benefits from the simplicity of the Linear Inverted Pendulum Model (LIPM), while it overcomes the common limitations of this model and enables us to generate a variety of whole body motions through external contacts. Simulation and experimental implementation of several whole body actions in multi-contact scenarios on a humanoid robot show the capability of the proposed algorithm. Copyright © 2018, The Authors. All rights reserved.

关键词： Anthropomorphic robots

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Elasticity modulus variation of the AISI SAE 1045 steel subjected to corrosion process by chloride using tension test destructive

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IOP Conference Series: Materials Science and engineering 2020年第1期844卷

作者： C G Cárdenas-Arias A D Rincón-Quintero A Santos-Jaimes C L Sandoval-Rodriguez D F Rojas-Gomez S J Ardila-Galvis Design and materials research group (DIMAT) Automation and Control Energy Systems Research Group (GISEAC) Electromechanical engineering Faculty of Natural Sciences and Engineering Technological Units of Santander (UTS) Calle de los estudiantes No 9-82 680005 Bucaramanga Colombia. Materials Research Group (GIM). Mechanical Engineering Engineer School Pontifical Bolivarian University (UPB) Kilometer 7 Highway Floridablanca – Piedecuesta (057) (7) 6799220 Floridablanca Colombia.

The study of materials corrosion effect is a great importance topic for the manufacturing industry and also for the customer that requires this. That is why a research study was conducted that aimed to determine the elasticity modulus variation of AISI SAE 1045 steel subjected to corrosion. To achieve this, thirty-five specimens were used, which were exposed to chlorides by immersion processes and salt spray chamber in three periods of time and then subjected to stress test destructive, following the guidelines established under ASTM G-1 standards, ASTM G-31 and ASTM E-8. Variation was found in the elastic behavior of steel and curves that differ from the theoretical ones raised in the documents.

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Performance analysis of a photovoltaics aided coal-fired power plant

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Energy Procedia 2019年 158卷 1348-1353页

作者： Mingkun Jiang Yuexia Lv Tiankun Wang Zunqiang Sun Jianmin Liu Xinhai Yu Jinyue Yan Key Laboratory of Pressure Systems and Safety (MOE) School of Mechanical Engineering East China University of Science and Technology Shanghai 200237 China State Key Laboratory of Clean and Efficient Coal-fired Power Generation and Pollution Control Guodian Science and Technology Research Institute Nanjing 210023 China Applied Energy Innovation Institute Ningbo 315201 China School of Mechanical & Automotive Engineering Qilu University of Technology (Shandong Academy of Sciences) Jinan China China Energy Group Beijing 100011 China School of Business Society and Technology Mälardalen University Västerås Sweden School of Chemical Science and Engineering Royal Institute of Technology Stockholm Sweden

In this article, integration of photovoltaics (PV) into a coal-fired power plant was proposed. The performance including economic analysis and environmental impact was conducted by a case study in the northwest area of China. The results show that the PV system can replace part of auxiliary power consumption using renewable electricity to reduce internal power consumption and the emissions. Due to the feature of the integration into a power plant, the curtailment of solar PV electricity does not occur compared to stand-alone PV system. The investment cost, operation and maintenance (O&M) expenditure were feasible compared with other PV power generation plants.

关键词： photovoltaics coal-fired power plants auxiliary power consumption

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Variable interface dynamic adjustment (VIDA) technique: A novel approach to adjust lagrangian frame and eulerian frame at flattering interface 8th

Variable interface dynamic adjustment (VIDA) technique: A no...

引用

8th AIAA Theoretical Fluid Mechanics Conference, 2017

作者： Zanj, Amir He, Fangpo Breedveld, Peter C. College of Science and Engineering Advanced Control Systems Research Group Flinders University Adelaide Australia Department of Mechanical engineering Robotics and Mechatronics Group University of Twente Enschede Netherlands

ISBN: (纸本)9781624104978

In the current study to address the incompatibility issue of the Eulerian and Lagrangian frame at FSI problems, a novel physical approach is proposed. According to this approach, the motion of the Lagrangian frame is physically translated to a virtual volumetric flow for the Eulerian frame. As thus, the shared spatial boundary of the two frame at the interface remains unique in spite of the motion of the interface. This capability provides the possibility of dynamic data transactions between the two frames, which guarantees the continuity of these transformation (e. g., the power interactions of the system on the interface). The obtained capability can be a desirable tool in multiple-field dynamic investigations. Also, the proposed method by elimination of mesh regeneration in FSI transient solutions can open a new window in dynamic mesh techniques which leads to reducing the time cost of the solution. © 2017, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.

关键词： Lagrange multipliers

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Approximated unbiased minimum-variance simultaneous states and parameters estimation for nonlinear systems

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IFAC-PapersOnLine 2017年第1期50卷 1607-1612页

作者： Ishihara S. Yamakita M. Hitachi Ltd. Research & Development Group Center for Technology Innovation Mechanical Engineering Ibaraki Japan Dept. of Systems and Control Engineering Tokyo Institute of Technology Tokyo Japan

This paper addresses joint state and parameter estimation problem for nonlinear systems. We linearize the nonlinear system by unscented statistical linearization (USL) and decouple unknown parameter vector of state vector. Then, we treat unknown parameter vector as unknown inputs to the approximated linear model. Furthermore, we applied unbiased minimum variance estimation (UMVE) method for the approximated linear system with unknown input. Our proposed method also offers an easy way to apply the UMVE to nonlinear systems. We confirm the validity of the proposed methods by Monte Carlo simulations. © 2017

关键词： Nonlinear filters Nonlinear sysytems Parameter estimation State estimation Uncertain dynamic systems

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