OUTPUT VIBRATION MONITORING DEVICE OF NUCLEAR REACTOR, METHOD AND PROGRAM

PROBLEM TO BE SOLVED: To provide a highly reliable output vibration monitoring technology of a nuclear reactor for suppressing that vibration components to be extracted abnormally changes when averaging processing is performed to a plurality of LPRM signals whose number to be calculated may change.SOLUTION: This output vibration monitoring device comprises: a receiving part 2 which allocates LPRM signals to specified cells to be received; an exclusion processing part 3 which retrieves LPRM signals corresponding to exclusion conditions among the LPRM signals allocated to the cells; an averaging part 4 which averages the LPRM signals for every cell to output an average flux value H; a time averaging part 5 which calculates time average of the average flux value H to output a time average flux value J; a standard value calculation part 6 which divides the average flux value H by the time average flux value J to output a standard value K; an initialization part 10 which outputs an initialization signal S when there are changes in the LPRM signals corresponding to the exclusion conditions; and a determination part 7 which executes determination based on a predetermined algorithm from the standard value K.