Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Artificial intelligence-based predictive modeling for imaging neutral particle analyzers on the DIII-D tokamak

Journal Article · · Nuclear Fusion
 [1];  [2];  [3];  [4];  [4];  [4];  [5]
  1. Oak Ridge Institute for Science and Education, Oak Ridge, TN (United States); Princeton University, NJ (United States)
  2. University of Illinois at Urbana-Champaign, IL (United States)
  3. General Atomics, San Diego, CA (United States)
  4. Princeton University, NJ (United States)
  5. Princeton University, NJ (United States); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
The Imaging Neutral Particle Analyzer (INPA) at DIII-D is a diagnostic system used to accurately resolve the energy and spatial distributions of fast ions in fusion plasmas. A novel artificial intelligence (AI) technique named INPA-net is based on Reservoir Computing Networks and developed here to predict active and passive signals produced by charge-exchange reactions from injected and edge-cold neutrals, respectively, in magnetically confined fusion plasmas. This model is trained using a set of 21 time domain signals between 0 s to 3.35 s that includes injected beam and thermal plasma information, and 6444 real 2D experimental images of the INPA in 12 plasma discharges at DIII-D. The trained neural network is able to forecast experimental images in real-time. The model achieves an R-squared value of 0.91, which is higher than the 0.83 value achieved by a simple linear regression model. This improvement highlights the model's enhanced predictive accuracy for measured images from the validation set. This AI approach is valuable due to its rapid response times and potential for integration into real-time plasma control systems. A version of this model capable of generating syntehic images would be useful for the real-time monitoring of fast-ion transport. A comprehensive sensitivity study reveals that INPA-net maintains high performance even with variations in the input parameters, indicating the model's robustness and reliability. While developed for the INPA, the underlying architecture is adaptable and may be applied to various 2D imaging diagnostics in fusion research.
Research Organization:
General Atomics, San Diego, CA (United States)
Sponsoring Organization:
USDOE; USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF); USDOE Office of Science (SC), Fusion Energy Sciences (FES)
Grant/Contract Number:
AC02-09CH11466; FC02-04ER54698; SC0014664; SC0024527
OSTI ID:
2553087
Alternate ID(s):
OSTI ID: 2539968
Journal Information:
Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 5 Vol. 65; ISSN 0029-5515
Publisher:
IOP ScienceCopyright Statement
Country of Publication:
United States
Language:
English

References (50)

Advancing Fusion with Machine Learning Research Needs Workshop Report journal August 2020
Introduction to the interaction between energetic particles and Alfven eigenmodes in toroidal plasmas journal December 2018
Clustering of periodic multichannel timeseries data with application to plasma fluctuations journal June 2014
PyRCN: A toolbox for exploration and application of Reservoir Computing Networks journal August 2022
Physics of the conceptual design of the ITER plasma control system journal May 2014
Deep learning journal May 2015
Predicting disruptive instabilities in controlled fusion plasmas through deep learning journal April 2019
Basic physics of Alfvén instabilities driven by energetic particles in toroidally confined plasmas journal May 2008
Extended fast-ion D-alpha diagnostic on DIII-D journal October 2010
Scintillator-based diagnostic for fast ion loss measurements on DIII-D journal October 2010
Machine learning control for disruption and tearing mode avoidance journal February 2020
Toroidal Alfvén eigenmode‐induced ripple trapping journal August 1995
Exploratory Machine Learning Studies for Disruption Prediction Using Large Databases on DIII-D journal February 2018
Fast-wave heating of a two-component plasma journal October 1975
Loss of energetic beam ions during TAE instabilities journal May 1993
ASCOT simulations of fast ion power loads to the plasma-facing components in ITER journal August 2009
Control of power, torque, and instability drive using in-shot variable neutral beam energy in tokamaks journal September 2016
Principles of Plasma Diagnostics: Second Edition journal November 2002
The role of energetic particles in fusion plasmas journal November 2004
Automatic disruption classification in JET with the ITER-like wall journal October 2015
Experiment-theory comparison for low frequency BAE modes in the strongly shaped H-1NF stellarator journal August 2015
Measurement of the passive fast-ion D-alpha emission on the NSTX-U tokamak journal January 2018
Disruption prediction investigations using Machine Learning tools on DIII-D and Alcator C-Mod journal June 2018
Active control of Alfvén eigenmodes in magnetically confined toroidal plasmas journal March 2019
Automatic identification of MHD modes in magnetic fluctuation spectrograms using deep learning techniques journal July 2021
Commissioning of the imaging neutral particle analyser for the ASDEX Upgrade tokamak journal February 2024
Adaptive predictors based on probabilistic SVM for real time disruption mitigation on JET journal March 2018
Development and verification of a novel scintillator-based, imaging neutral particle analyzer in DIII-D tokamak journal June 2018
Active real-time control of Alfvén eigenmodes by neutral beam and electron cyclotron heating in the DIII-D tokamak journal September 2018
Machine learning for disruption warnings on Alcator C-Mod, DIII-D, and EAST journal July 2019
Validation of the imaging neutral particle analyzer in nearly MHD quiescent plasmas using injected beam ions on DIII-D journal August 2020
‘BAAE’ instabilities observed without fast ion drive journal December 2020
Stability of beta-induced Alfvén eigenmodes (BAE) in DIII-D journal May 2021
Alfvén eigenmode classification based on ECE diagnostics at DIII-D using deep recurrent neural networks journal December 2021
The radial phase variation of reversed-shear and toroidicity-induced Alfvén eigenmodes in DIII-D journal April 2022
Disruption prediction at JET through deep convolutional neural networks using spatiotemporal information from plasma profiles journal April 2022
Modelling the Alfvén eigenmode induced fast-ion flow measured by an imaging neutral particle analyzer journal September 2022
Exploring data-driven models for spatiotemporally local classification of Alfvén eigenmodes journal August 2022
Comparison of machine learning systems trained to detect Alfvén eigenmodes using the CO2 interferometer on DIII-D journal October 2023
Visualization of phase-space orbit topological boundary using imaging neutral particle analyzer journal October 2023
Initial testing of Alfvén eigenmode feedback control with machine-learning observers on DIII-D journal July 2024
Neural networks for reconstruction and uncertainty quantification of fast-ion phase-space distributions using FILD and INPA measurements journal November 2024
Imaging Neutral Particle Analyzer (INPA) measurements of confined fast ions in DIII-D journal September 2019
Visualization of Fast Ion Phase-Space Flow Driven by Alfvén Instabilities journal December 2021
Physics of Alfvén waves and energetic particles in burning plasmas journal March 2016
Alfvén eigenmode detection using Long-Short Term Memory Networks and CO2 Interferometer data on the DIII-D National Fusion Facility conference June 2023
Machine Learning Characterization of Alfvénic and Sub-Alfvénic Chirping and Correlation With Fast-Ion Loss at NSTX journal January 2020
MHD and Plasma Control in ITER journal April 2011
Contemporary Instrumentation and Application of Charge Exchange Neutral Particle Diagnostics in Magnetic Fusion Experiments report July 2007
Multipitch tracking in music signals using Echo State Networks conference January 2021