Coil Power-Supply Switching Control
Fast switching supplies drive the coil currents both machines depend on; L1 controls their switching deterministically to deliver clean, bounded current.
Supplies as the muscle behind the coils
Every field the control loops command is realized by a power supply pushing current through a coil. Kronos uses fast switching converters whose output current tracks L1's demand. The switching itself — the gating of the power devices — is a deterministic control task: it sets how fast and how cleanly the coil current follows the setpoint the shape, position, or plug loops request.
Current-mode inner loop
Each supply closes a fast current-control inner loop: it modulates its switching duty to make output current equal the demand, rejecting back-EMF and load changes. This inner loop turns the coil-plus-supply into a predictable actuator for the outer plasma loops, which is the pattern used throughout RT-compute actuators. The switching frequency and control bandwidth are chosen so the coil current has the response the outer loop assumes.
Deterministic switching
- Gate timing referenced to the shared clock to bound jitter.
- Current, voltage, and di/dt limits enforced locally.
- Coordinated turn-on/off to avoid cross-supply transients.
- Fast, controlled ramp paths for current ramp-down and dumps.
The supplies also participate in protection: a controlled current ramp-down for disruption handling, or a coordinated de-energization during a magnet event, is executed through the same supplies under L1's timing guarantees. Their di/dt limits protect both the coil insulation and the plasma from abrupt field changes.
Both machines' coil sets
The breeder's central solenoid, toroidal-field, PF and vertical-control coils, and the burner's plug, throat, and central-cell magnets are all driven this way. Different power levels and dynamics, one control discipline: deterministic switching that makes coil current a clean, bounded actuator for the loops above.