Preliminary sizing and operation analysis of the DTT electrical network system

The Divertor Tokamak Test (DTT) facility plays a crucial role in the European Roadmap for fusion energy. Its primary goal is to explore solutions for the power exhaust in the DEMO divertor. The two most power-consuming systems in DTT are: the Heating and Current Drive systems, which deliver up to 45 MW of power to the plasma (totaling to approximately 150 MVA installed), and the coil Power Supply System. An Electrical Network System was designed for this purpose, fed at 150 kV by the National Grid (NG), requiring up to 300 MVA. The large power time derivatives in a very short time, peculiar of the abovementioned loads, hardly allow for the adoption of solutions to stabilize the voltage. On the other hand, such loads are controlled by electronic converters with specific needs on the waveform quality but also with the capability to partially compensate the voltage fluctuations. To this end, these loads are grouped in a sub-network with less stringent requirements than other loads. To validate the preliminary design choices, a simulation model was implemented in the DIgSILENT PowerFactory software. This paper presents the results of preliminary static and dynamic simulations of the ENS, to validate adequate sizing, stability, and impact towards the NG.