Quench detection and data acquisition system for SST-1 superconducting magnets

Superconducting magnet system of steady state superconducting Tokamak (SST-1) shall be operating in a very noisy environment. Presences of high inductive voltages in the magnets during off-normal events like VDE, plasma disruption and PF magnet ramp ups, etc. has made quench detection and data acquisition a challenging task. A hybrid of analog electronic circuits and software-controlled data acquisition system has been developed and tested to safeguard the magnets. This paper will describe the electronic hardware circuits developed for signal conditioning, high voltage suppression, fail-proof quench detection and for noise elimination algorithms and their testing. T-1 superconducting magnets will have large number of sensors like voltage taps, Venturi flow meter, strain gages, hall probes, pressure sensors, temperature sensors and displacement transducers. A real time data acquisition system has been designed using VMEbus for monitoring and storing signals from all these sensors and initiating control action in case of off-normal events. The paper will also describe the configuration of the data acquisition system with emphasis on hardware used and the software developed for it.