TRANSP-based closed-loop simulations of current profile optimal regulation in NSTX-Upgrade

Journal Article · Mon Feb 18 23:00:00 EST 2019 · Fusion Engineering and Design

DOI:https://doi.org/10.1016/j.fusengdes.2019.01.021· OSTI ID:1503680

Ilhan, Zeki O. ^[1]; Boyer, Mark D. ^[2]; Schuster, Eugenio ^[1]

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1. Lehigh Univ., Bethlehem, PA (United States)
2. Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States)

Active control of the toroidal current density profile is critical for the upgraded National Spherical Torus eXperiment device (NSTX-U) to maintain operation at the desired high-performance, MHD-stable, plasma regime. Initial efforts towards current density profile control have led to the development of a control-oriented, physics-based, plasma-response model, which combines the magnetic diffusion equation with empirical correlations for the kinetic profiles and the non-inductive current sources. The developed control-oriented model has been successfully tailored to the NSTX-U geometry and actuators. Moreover, a series of efforts have been made towards the design of model-based controllers, including a linear-quadratic-integral optimal control strategy that can regulate the current density profile around a prescribed target profile while rejecting disturbances. In this work, the tracking performance of the proposed current-profile optimal controller is tested in numerical simulations based on the physics-oriented code TRANSP. Furthermore, these high-fidelity closed-loop simulations, which are a critical step before experimental implementation and testing, are enabled by a flexible framework recently developed to perform feedback control design and simulation in TRANSP.

• Research Organization: Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)
• Sponsoring Organization: USDOE
• Grant/Contract Number: AC02-09CH11466
• OSTI ID: 1503680
• Alternate ID(s): OSTI ID: 1557897
• Journal Information: Fusion Engineering and Design, Journal Name: Fusion Engineering and Design Vol. 146; ISSN 0920-3796
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
Current profile control
Model-based control
Optimal control
Plasma control
TRANSP-based simulation