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Energy and the grid · In service today

Fault-current limiters

Goes normal in a millisecond and swallows a short circuit.

The record behind fault-current limiters

Fault-current limiters against a real short circuit · Energies

Superconductors in fault-current limiters

This is the one application that uses a superconductor’s failure as the feature. Below the design current the device is invisible: no resistance, no loss, no voltage drop. Above it the conductor goes normal on its own and becomes a resistance in the path of the fault, limiting it before a breaker has finished deciding what to do. Nothing else in a grid does that passively, and it lets a utility add generation to a network whose existing switchgear would otherwise have to be replaced.

What is stopping fault-current limiters

Recovery. The element has to go normal, absorb the fault energy without damaging itself, and cool back down fast enough to be ready for the next one. That thermal cycle is what sets the amount of conductor in the device, and therefore the price.

What a better material would change for fault-current limiters

Both the size and the price come down with the conductor. A material that absorbed the fault energy without degrading, and cooled back faster afterward, would make the device smaller and the recovery window shorter, and the recovery window is what a utility is actually buying.

Conductors used in fault-current limiters

Near fault-current limiters, in energy and the grid

SuperMatics is a platform infrastructure company for superconducting devices: software that finds the material and the process, lab work that makes and measures it, and pilot manufacturing with industrial partners.If you are working on something in this field and a material is what stands in the way, tell us about it.