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Title: Fast Numerical Solution of the Plasma Response Matrix for Real-time Ideal MHD Control

Journal Article · · Physics of Plasmas
DOI:https://doi.org/10.1063/1.5007042· OSTI ID:1418995
 [1];  [2]; ORCiD logo [3]
  1. Princeton Univ., NJ (United States). Dept. of Astrophysical Sciences
  2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)
  3. Fusion Theory and Computation, Inc., Kingston, WA (United States)

To help effectuate near real-time feedback control of ideal MHD instabilities in tokamak geometries, a parallelized version of A.H. Glasser’s DCON (Direct Criterion of Newcomb) code is developed. To motivate the numerical implementation, we first solve DCON’s δW formulation with a Hamilton-Jacobi theory, elucidating analytical and numerical features of the ideal MHD stability problem. The plasma response matrix is demonstrated to be the solution of an ideal MHD Riccati equation. We then describe our adaptation of DCON with numerical methods natural to solutions of the Riccati equation, parallelizing it to enable its operation in near real-time. We replace DCON’s serial integration of perturbed modes—which satisfy a singular Euler- Lagrange equation—with a domain-decomposed integration of state transition matrices. Output is shown to match results from DCON with high accuracy, and with computation time < 1s. Such computational speed may enable active feedback ideal MHD stability control, especially in plasmas whose ideal MHD equilibria evolve with inductive timescale $$\tau$$ ≳ 1s—as in ITER. Further potential applications of this theory are discussed.

Research Organization:
Fusion Theory and Computation, Inc., Kingston, WA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
Grant/Contract Number:
SC0016106; AC02-09CH11466; FOA-0001386: Early Career Research Program
OSTI ID:
1418995
Alternate ID(s):
OSTI ID: 1429578
Journal Information:
Physics of Plasmas, Vol. 25, Issue 3; ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)Copyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 9 works
Citation information provided by
Web of Science

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Cited By (3)

A robust solution for the resistive MHD toroidal Δ′ matrix in near real-time journal August 2018
Progress in disruption prevention for ITER journal June 2019
A Riccati Solution for the Ideal MHD Plasma Response with Applications to Real-time Stability Control dataset January 2018

Figures / Tables (4)