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Title: Development of real-time density feedback control on MAST-U in L-mode

Journal Article · · Fusion Engineering and Design
ORCiD logo [1]; ORCiD logo [1]; ORCiD logo [2];  [2]; ORCiD logo [2]; ORCiD logo [1]; ORCiD logo [3];  [2];  [2];  [2];  [2]; ORCiD logo [4]; ORCiD logo [1]
  1. Eindhoven Univ. of Technology (Netherlands). Dutch Institute for Fundamental Energy Research (DIFFER)
  2. Culham Science Centre, Abingdon (United Kingdom). Culham Centre for Fusion Energy (CCFE), EURATOM/UKAEA Fusion Association
  3. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
  4. Culham Science Centre, Abingdon (United Kingdom). Culham Centre for Fusion Energy (CCFE), EURATOM/UKAEA Fusion Association; Univ. of York (United Kingdom)

In this paper we report on the development and demonstration of density feedback control for MAST-U. Sinusoidal perturbations are used to measure the frequency response from a deuterium gas valve (actuator) to line-integrated core electron density measured by the interferometer (sensor). In the frequency range relevant for control design, only two system-identification experiments were needed to regress a first-order dynamic model. This control-oriented model informs the offline design of a proportional integral controller with the established loop-shaping controller design method. After offline verification of the controller implementation, control is demonstrated by experimentally tracking a staircase reference for the line-integrated electron density. This paper demonstrates the efficiency of controller design using system-identification and loop-shaping, providing reliable density control for MAST-U.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE Office of Science (SC)
Contributing Organization:
EUROFUSION TOKAMAK EXPLOITATION TEAM; MAST-U team
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
2333742
Journal Information:
Fusion Engineering and Design, Journal Name: Fusion Engineering and Design Vol. 202; ISSN 0920-3796
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English

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