Preliminary operational results of the new coil protection system for TFTR

An advanced, microcomputer-based, coil monitoring and protection system has been designed, built, and installed at the TFTR (Tokamak Fusion Test Reactor). The TFTR coil protection system is summarized, and the results of preliminary testing are shown. Comparisons are made between coil stress levels calculated by the new coil protection system and stress levels calculated using the TFTR systems code. The comparison of stress and temperature profiles shows close agreement between the two systems. The microprocessor-based system used at TFTR is necessarily executing much simpler code, but any differences in the results will show the new protection system to be conservative. The user interface between this stand-alone protection system and CICADA, TFTR´s central computer data-acquisition and control system, is also described. The interface with CICADA provides control-room personnel with valuable, real-time displays of coil stresses and coil temperatures as well as important status information related to the proper operation of the protection system. Discussion of the control room provides some insight into the features of the coil protection system