Generation of fast dump trigger of main magnet coil of K-500 superconducting cyclotron at VEC Centre, Kolkata

Some safety precautions is adopted for magnet start-up, current ramping, automatic magnet turn-off conditions and fast dump conditions. Among them, magnet turn-off conditions-ramp to 0/0 and fast dump conditions require monitoring of lead voltage and some parameters directly related to the cryostat pressure, helium level, cryostat vacuum and support link force. Another important life-threatening situation for the magnet is quench of anyone coil of the magnet, while fast dump trigger should be generated. All these important signals are combined to generate a fast dump trigger signal. It makes or breaks associated circuit breaker for isolating power converter and connecting fast dump resistor to the magnet coil to decay stored energy. The paper describes all the key features of quench detection circuit, current lead voltage monitoring and generation of fast dump trigger signal. (author)