Safety Interlock Implementation Using FPGA
The Fuel Handling Control System (FHCS) of Advanced Heavy Water Reactor (AHWR) is used for the
refueling operation and control of Fueling Machine (FM), Fuel Transfer Machine (FTM) and other fuel handling
equipments. The FHCS is designed to operate in Auto as well as in Manual mode. FHCS deploys two sets of Control
Computers for FM and FTM auto operations respectively. Control Computers issue command to the field after verifying the
interlocks coded in software. This paper summarizes the safety operation of Fuel handling equipments by checking these
output commands given by Control Computer after verifying again through a separate standalone hardwired Manual Safety
Logic (MSL) Unit. Manual Safety Logic Unit implements the interlocks using Field Programmable Gate Array (FPGA).
This provides an independent and diversified implementation to prevent any maloperation of the system and takes the system
to the safe state during any fault conditions.
Index Terms— Control System, Modes of Operation, MSL Unit.