Design for the upgrade of the Fast Sequence Control for Frascati Tokamak Upgrade

In ENEA Frascati research centre an experimental fusion machine called Frascati Tokamak Upgrade (FTU) is in operation since 1990. During the experimental activity, the automatic control and synchronization of many plants are required. The FTU control system [1] includes many sub-systems having different roles [2, 3]. In particular, a Fast Sequence Control (FSC) hardware is necessary to drive the tokamak power plants and to detect the errors in the fast control sequence during the plasma discharge. The FSC system was designed and realized in 1980s and is still in operation. Due to the obsolescence of some hardware components, a new project for the FSC Upgrade (FSCU) has been started. The project includes a new architecture based on up-to-date commercial hardware and dedicated firmware and software. In the present paper the architecture and the functions of the Fast Sequence Control - Upgrade system is described, along with the main differences between the two systems.