HIGH VOLTAGE CONTROLLER SYSTEM FOR SPECTROSCOPY DIAGNOSTICS OF SST-1

We have developed special instrumentation for spectroscopy diagnostics of the SST- 1 Tokamak. Light output in the visible spectrum is guided through fiber optics from the Tokamak ports to the diagnostics Hall, where photo multipliers tubes and other instrumentation electronics are kept. High Voltage (0 - 1500 V) bias generation electronics is required to bias these PMTs. Total 14 PMTs to be biased for overall requirements of the diagnostics. We have developed modular electronics for HV bias generation, which consist of one controller and seven HV modules. We have designed and developed FPGA based controller card which controls seven HV modules. The Slot-0 card is having Spartan 3E FPGA and Standalone Controller Area Networking (CAN) controller. 32-bit RISC processor Microblaze has been deployed into the FPGA. We have used Hitek make HV supply modules which is programmable. In the HV modules, Analog Device Inc. make iCoupler, digital isolators are used to break the ground loops and to avoid ground-lifting problem. Various features like Manual mode/Remote mode operation, HV ON/OFF, HV Value setting through remote GUI have been developed on LabVIEW software.