The MHD Control System for the FTU Tokamak

In this paper the architecture of the MHD control system for the Frascati Tokamak Upgrade (FTU) is presented. This control is aimed to stabilize tearing modes (TM) in the plasma by EC heating and current drive. TMs are detected and spatially localized by correlating several ECE channels and Mirnov coil signals; two independent antennas are steered in order to track the TM instability. To guarantee short locking time a fast real-time plasma equilibrium code is used to locate the instability when there is no TM evidence and real-time ray tracing code is used to estimate the location where EC power is deposited. A set of hardware consisting of FPGA and DSP modules on PXI bus for executing the diagnosis and control algorithms is proposed. The overall system layout is introduced together with a description of the data communication among the processors.