Real-Time Plasma Flight Simulators
A plasma flight simulator runs a fast physics model in place of the real machine so controllers can be tested and tuned before a discharge.
The idea
A flight simulator for a fusion device couples a control-oriented plasma model to the actual control software, running in a loop that mimics a real discharge. The controller cannot tell whether it is talking to hardware or to the model. This lets operators rehearse scenarios, tune gains, and check off-normal responses without risking the machine.
What the model must capture
A useful simulator is fast but faithful in the quantities the controller acts on: plasma current, shape and position, stored energy, density, and the profiles that set stability limits. It does not need first-principles turbulence; it needs the right input-output response over the control bandwidth. Reduced models and lookup tables are common.
Hardware-in-the-loop
When the simulator runs on the real control hardware at real-time speed, it is called hardware-in-the-loop testing. This exposes timing bugs, network faults, and integer overflows that a pure software test would miss. It is the closest a controller comes to flight before its first shot.
Uses across the life cycle
- Commissioning new controllers safely
- Operator training on rare fault sequences
- Regression testing after software changes
- Pre-shot rehearsal of a planned scenario
- Root-cause study of an anomalous discharge
In the Kronos program
Because the Hyperion breeder and the burner generators are still design and simulation devices, their flight simulators do double duty: they validate control designs and they let the team explore scenarios that hardware will only see after construction begins in the second quarter of 2027. The same reduced models that drive the simulator also feed the digital twin and the trajectory optimizer, so a scenario proven in simulation carries forward consistently.