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Title: Hybrid model predictive control techniques for safety factor profile and stored energy regulation while incorporating NBI constraints

Journal Article · · Nuclear Fusion

Abstract A novel hybrid Model Predictive Control (MPC) algorithm has been designed for simultaneous safety factor ( q ) profile and stored energy ( w ) control while incorporating the pulse-width-modulation constraints associated with the neutral beam injection (NBI) system. Regulation of the q -profile has been extensively shown to be a key factor for improved confinement as well as non-inductive sustainment of the plasma current. Simultaneous control of w is necessary to prevent the triggering of pressure-driven magnetohydrodynamic instabilities as the controller shapes the q profile. Conventional MPC schemes proposed for q -profile control have considered the NBI powers as continuous-time signals, ignoring the discrete-time nature of these actuators and leading in some cases to performance loss. The hybrid MPC scheme in this work has the capability of incorporating the discrete-time actuator dynamics as additional constraints. In nonlinear simulations, the proposed hybrid MPC scheme demonstrates improved q -profile+ w control performance for NSTX-U operating scenarios.

Sponsoring Organization:
USDOE Office of Science (SC), Fusion Energy Sciences (FES)
Grant/Contract Number:
SC0021385
OSTI ID:
2396062
Alternate ID(s):
OSTI ID: 2377893
Journal Information:
Nuclear Fusion, Journal Name: Nuclear Fusion Journal Issue: 8 Vol. 64; ISSN 0029-5515
Publisher:
IOP PublishingCopyright Statement
Country of Publication:
IAEA
Language:
English

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