DEVICE, METHOD AND PROGRAM FOR MONITORING NUCLEAR THERMAL-HYDRAULIC STABILITY OF NUCLEAR REACTOR

摘要

PROBLEM TO BE SOLVED: To provide a technique of improving the monitoring accuracy and reliability of the nuclear thermal-hydraulic stability of a nuclear reactor.SOLUTION: A monitoring device 50 includes: damping ratio calculation units 52 which calculate the damping ratios of nuclear instrumentation signals S output from a plurality of nuclear instrumentation detectors 31 to detect neutrons in a nuclear core 16; a destabilization index computation unit 54 which counts the damping ratios exceeding a first reference value D out of a plurality of the damping ratios to compute a destabilization index R of the nuclear core 16; and a start instruction unit 56 which instructs the start of output suppression means 60 of the nuclear core 16 when the destabilization index R exceeds a second reference value P.