Plasma Control Simulation Codes
Control simulation codes model the plasma as a dynamic system with sensors and actuators to design and test the feedback that holds a discharge.
The plasma as a control plant
A tokamak plasma is unstable in position and shape and must be actively controlled. Plasma control simulation codes treat the plasma, coils, sensors, and power supplies as a coupled dynamic system, building a model that maps actuator commands to sensor responses so that feedback controllers can be designed and tested before they run on hardware.
These codes bridge plasma physics and control engineering. They linearize the plasma response about an operating point, or use a nonlinear evolution, and wrap it with the real diagnostic and actuator dynamics.
Vertical stability and shape control
Elongated plasmas are vertically unstable on the timescale set by the conducting structures, and a controller must react faster than the growth rate. Control codes compute this open-loop growth rate from a free-boundary model and verify that the designed feedback stabilizes it with realistic power-supply limits.
Scenario and event handling
Beyond stabilization, control codes test the full discharge sequence, ramp-up, flat-top regulation of shape and profiles, and controlled ramp-down, and the response to off-normal events, feeding into disruption avoidance and mitigation strategies.
Design relevance
For the Hyperion breeder, a strongly shaped spherical tokamak, control simulation confirms in advance that a physical coil and power-supply set can hold the negative-triangularity, -0.30, shape and stabilize the vertical mode. This design-stage verification precedes construction, which begins Q2 2027.
- Models plasma, coils, sensors, actuators together
- Designs and tests feedback controllers
- Verifies vertical and shape stabilization
- Covers full discharge scenarios and off-normal events