Eugenio Schuster (Lehigh University)
Title: Sequential Suboptimal Control of Current Profile Dynamics in Tokamak Plasmas
Abstract: We present a framework to solve a finite-time optimal control problem for parabolic partial differential equations with diffusivity-interior actuators, which is motivated by the control of the current density profile in tokamak plasmas. By using proper orthogonal decomposition and Galerkin projection we obtain a bilinear reduced-order model that preserves the most energetic modes of the system. Based on quasi-linearization of the optimality conditions derived from Pontryagin's principle, and stated as a two-boundary-value problem, we propose a convergent iterative scheme for suboptimal closed-loop control which avoids repeated numerical computation of the Riccati equation and reduces in this way the number of ordinary differential equations that must be solved at each iteration step.