Heating Power Control

Heating power control modulates auxiliary systems to regulate temperature, stored energy, and profiles while respecting source limits.

The heating systems

Auxiliary heating raises the plasma temperature toward fusion-relevant conditions and shapes profiles. The main systems are neutral beam injection, which fires energetic neutral atoms into the plasma, and radio-frequency heating at the ion or electron cyclotron frequencies. Each has a controllable power level and, for the wave systems, a controllable deposition location.

What heating control regulates

Heating power is the primary actuator for stored energy and temperature control, and, through localized deposition, a tool for profile and instability control. A single heating request often serves several goals at once, which is why heating sits at the center of actuator allocation.

Modulation and constraints

Sources have minimum and maximum power, finite ramp rates, and duty-cycle limits. Neutral beams may only operate in discrete steps rather than continuously. Controllers respect these by using the available modulation granularity and by combining sources so that the aggregate power is smooth even when individual sources switch.

Deposition control

For wave systems, steering the deposition changes which physics goal is served: central deposition heats the core and can control sawteeth, off-axis deposition broadens profiles and drives current. Real-time steering mirrors let one system move between roles within a discharge under supervisor control.

In the Kronos program

The Hyperion breeder's heating systems support the stored-energy loop that holds it at 88.7 megawatts of fusion power and are shared, through allocation, with sawtooth, tearing-mode, and profile control. The burner generators use their own heating and sustainment scheme suited to a tandem mirror. Heating control schemes are validated in simulation before operation.