The delivery of the first Fast Discharge Unit (FDU)
On January 15 2025, another DTT component arrived at Frascati: the first Fast Discharge Unit (FDU), a key component for the protection of the DTT magnet system, manufactured by OCEM Energy Technology.
The FDU can interrupt 44'000 A in direct current (DC) and can safely discharge in few seconds the large energy stored in the superconducting coils. It is the first realization worldwide based on a totally electronic switch and on nonlinear resistors. The FDU was accepted after passing tests above 17'000 A in an independent laboratory in Berlin, Germany.
This FDU will be temporarily installed in the Cold Test Facility where all the DTT Nb3Sn superconducting coils will be tested at full current (up to 44'000 A) in relevant cryogenic conditions (-269 °C) before their assembly in the tokamak.
This FDU will be temporarily installed in the Cold Test Facility where all the DTT Nb3Sn superconducting coils will be tested at full current (up to 44'000 A) in relevant cryogenic conditions (-269 °C) before their assembly in the tokamak.
Once completed the cold tests of the superconducting coils, the FDU will be installed close to the DTT hall to protect its 18 toroidal field coils.
