Control System for 20 MeV Microtron

J.S.Adhikari, Y.Seth, B.J.Vaidya, S.S.Ramamurthi
Centre for Advanced Technology, Indore, India


Microtron of 20 MeV energy and 30 mA pulse current was designed, developed and commissioned as an injector to 700 MeV booster synchrotron. It is a part of Indus-I (450 MeV) and Indus-II (2 GeV) storage ring. The pulse length required is 2 microsec. at 1 Hz repetition rate. All the major components are placed around this vertical, 22 orbit microtron and same are controlled from separate control room isolated with almost two meter thick concrete wall. Control system is designed such that it can be operated from local control room and as well as from central control room of Indus-I and Indus-II. PC/AT is used as operator console which is down connected via serial link to supervisory control and data acquisition system (SCADAS). SCADAS is based on VMEbus architecture. Setting and reading is done via 4 to 20 mA current loop with isolation amplifier for noisy system like rf modulator and driver. Effective shielding of cables were provided to reduce effect of 2 microsec. pulse switching at nearly130 KV in modulator. Time synchronization of modulator pulse is done at zero crossover of cathode power supply.