Closed-loop Tracking Control of Poloidal Magnetic Flux Profile in Tokamaks
Y. Ou, C. Xu, E. Schuster, T. C. Luce, J. R. Ferron, M. L. Walker and D. A. Humphreys
American Control Conference
Seattle, Washington, June 11-13, 2008
Abstract
|
|
The potential operation of a tokamak fusion reactor
in a highly-efficient, steady-state mode is directly related to
the achievement of certain types of radial profiles for the current
flowing toroidally in the reactor. The time evolution of the
toroidal current profile is related to the poloidal magnetic flux
profile evolution, which is modeled in cylindrical coordinates
using a nonlinear partial differential equation (PDE) usually
referred to as the magnetic diffusion equation. In this paper,
we propose a framework to solve a closed-loop, finite-time,
optimal tracking control problem for the poloidal magnetic
flux profile via diffusivity, interior, and boundary actuation.
The proposed approach is based on reduced order modeling via
proper orthogonal decomposition (POD) and successive optimal
control computation for a bilinear system. Simulation results
illustrate the performance of the proposed controller.