Coil Forces and Structure
At 16.84 T the coils experience immense centering and hoop forces; the structure that reacts them is as much a part of the magnet as the conductor.
Force comes with field
Magnetic field stores energy, and gradients in it produce force. At Hyperion's 16.84 T peak the toroidal-field coils are pulled inward toward the machine axis by centering forces, and every current-carrying loop feels an outward hoop force trying to expand it. These loads are enormous and continuous during operation.
Reacting the loads
The center stack acts as a compression column that resists the inward centering force of all the toroidal-field coils together. Outboard, structural cases and support rings carry hoop and overturning loads. In a REBCO magnet the thin superconducting tape cannot carry these forces itself, so the surrounding structure must take essentially all of the mechanical load while keeping strain on the conductor within the limit above which its current-carrying capacity degrades.
Coupled to everything
Coil forces couple to the whole machine: they set the center-post diameter, constrain how much shielding fits inboard, and interact with the vacuum-vessel supports. Because the plasma current and shaping change through a discharge, the loads are also dynamic, and fault cases such as a disruption or a magnet quench impose transient forces the structure must survive. Structural analysis and the magnet design advance together throughout the design-and-simulation program.
- Inward centering forces reacted by the center stack
- Outward hoop forces reacted by cases and support rings
- Conductor strain kept below the degradation limit
This page describes a design and simulation study, not a built machine. Construction begins Q2 2027; first-of-a-kind first tritium is targeted near 2030.