Research Needs for Magnetic Fusion Energy Sciences - US Burning ...

Relation to Other Thrusts
The proposed Thrust combines many diverse elements, and key research requirements of several
of the Theme 1 and 2 panels, into a single comprehensive and coordinated program where the
research needs for actuators, diagnostics, and control algorithms are defined by control needs.
many of the specific elements themselves require a concerted and focused development effort,
and some of these are important and large enough that they should be provided by other thrusts.
specific examples include the development of target scenarios for iteR and beyond (Thrusts 4
and 8), understanding and mitigation of plasma event induced transient events appropriate to
iteR (Thrust 2), and the role of non-axisymmetric fields in improving performance (Thrust 17).
diagnostics are an integral part of plasma control. diagnostic developments in a burning highfluence
fusion environment are the focus of Thrust 1 and strong coordination with this Thrust is
required to specify those needs that are crucial for control, and incorporate realistic inputs into
real-time systems. While some development of physics and actuators for iteR will be done in
Thrust 4, developments for demo are primarily within this Thrust. Thrust 6 is expected to provide
the simulation and knowledge basis for developing control-level models. integrated demonstration
of plasma boundary solutions compatible with core scenarios is undertaken in Thrust 12.
Thrust 5 will in turn provide control and sustainment tools that enable the long pulse integration
facility of Thrust 12. in each case, it is expected that those elements necessary for the success of
the control mission will be coordinated so that solutions to specific issues found in other thrusts
can be incorporated into a control system in a timely manner.
benefit to DOE
This Thrust, if fully implemented, would have an enormous impact on the fusion program. a definitive
answer to the performance limit for robust advanced tokamak scenarios will inform and
have an impact on the vision of a fusion reactor, and allow comparison of the different limits and
issues of other magnetic configurations. some of the issues are generic to any fusion reactor —
specifically, thermal stability and handling of off-normal events. This Thrust also has potential
for a considerable number of spin-offs outside fusion: algorithms for coupling actuators and sensors
in a highly nonlinear, near-marginal system with multiple time and length scales. also, the
development of new actuators — such as new radiofrequency or beam sources — needed for controlling
the self-heated, self-organized plasma may have applications to other fields such as high-
energy physics.
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