An Advanced Core Protection Calculator System Development

The Reactor COre Protection System (RCOPS), an advanced core protection calculator system, is a digital I and C system which provides core protection function based on two reactor core operation parameters, Departure from Nucleate Boiling Ratio (DNBR) and Local Power Density (LPD). It generates a reactor trip signal when the core condition exceeds the DNBR or LPD design limit. The RCOPS configuration, algorithm, and software are presented in this paper. RCOPS software has been implemented on one channel out of four RCOPS channels. Each channel of RCOPS consists of 4 sub-racks and shares the penalty factor with the other 3 channels. Through this configuration change, the number of processors per channel has been reduced from 6 to 4. RCOPS software is implemented adopting an improved DNBR algorithm (CETOP-D) to increase the core thermal margin, improving Control Element Assembly (CEA) signal validation logic to resolve the latching problem of CEA position signal, and generating auxiliary pre-trip alarms, etc. RCOPS Software consists of functional block diagram and C-language for custom block diagram