Transport Parameter Estimations of Plasma Transport Dynamics using the Extended Kalman Filter

A. Pajares and E. Schuster

IEEE Transactions on Plasma Science, vol. 48, no. 6, pp. 1606-12, June 2020

Abstract

Integrated-control solutions will play a significant role in future tokamaks, in which a variety of coupled control problems will need to be solved simultaneously by means of a limited number of actuators. In this article, the problem of simultaneously regulating the global toroidal rotation and total plasma energy is tackled. These two 0-D variables depend on the ion toroidal rotation and electron temperature profiles, respectively. Both the global toroidal rotation and the total plasma energy also depend on the electron density and safety factor profiles. The actuation methods considered in this article are co-current and counter-current neutral beam injection. A nonlinear, robust controller that makes use of Lyapunov redesign techniques is s ynthesized based on 0-D, control-oriented models of the global toroidal rotation and total plasma energy dynamics. In addition, an actuator management scheme is designed to handle variations in the control priorities and availability of the neutral beam injectors. The actuator manager solves an optimization problem in real time in order to find the most appropriate course of action when unexpected changes occur. The integrated control architecture is tested for a DIII-D scenario by means of the 1-D code Control-Oriented Transport Simulator (COTSIM), which predicts the time evolution of the electron temperature, electron density, ion toroidal rotation, and safety factor profiles.