Instantaneous control strategies for magnetically confined fusion plasma

TL;DR

This paper introduces an instantaneous feedback control method for guiding magnetically confined plasma within a specified region, using a Vlasov equation model with numerical validation to demonstrate effectiveness.

Contribution

It presents a novel real-time control strategy for plasma confinement based on the Vlasov equation, integrating cost minimization directly into particle interactions.

Findings

Control effectively steers plasma away from boundaries.

Feedback approach based on instantaneous system prediction.

Numerical simulations confirm the method's validity.

Abstract

The principle behind magnetic fusion is to confine high temperature plasma inside a device in such a way that the nuclei of deuterium and tritium joining together can release energy. The high temperatures generated needs the plasma to be isolated from the wall of the device to avoid damages and the scope of external magnetic fields is to achieve this goal. In this paper, to face this challenge from a numerical perspective, we propose an instantaneous control mathematical approach to steer a plasma into a given spatial region. From the modeling point of view, we focus on the Vlasov equation in a bounded domain with self induced electric field and an external strong magnetic field. The main feature of the control strategy employed is that it provides a feedback on the equation of motion based on an instantaneous prediction of the discretized system. This permits to directly embed the minimization of a given cost functional into the particle interactions of the corresponding Vlasov model. The numerical results demonstrate the validity of our control approach and the capability of an external magnetic field, even if in a simplified setting, to lead the plasma far from the boundaries.