Patent ID: 9595356
Date: 2017-03-14
CPC Classifications: G21C,Y02E

Claim:
1. A reactor oscillation power range monitor comprising: a receiving unit which receives local power range monitor (LPRM) signals generated from a plurality of LPRM detectors provided in a reactor core, the LPRM detectors distributed over the entire reactor core into several groups in a regular manner, each group classified as a cell and each of the LPRM signals allocated to a specified cell; an exclusion processing unit which searches the LPRM signals allocated to each cell for an LPRM signal corresponding to an exceptional condition, wherein the exceptional condition determines a LPRM signal unsuitable for a power oscillation monitoring; an averaging unit which averages the allocated LPRM signals for each of the cells by excluding the LPRM signals corresponding to the exceptional condition and outputs an average flux value; a time averaging unit which calculates a time average of the average flux value and outputs a time averaged flux value; a normalized value calculation unit which divides the average flux value by the time averaged flux value and outputs a normalized value; an initialization unit which outputs an initialization signal when a value of an LPRM signal changes to correspond or not correspond to the exceptional condition, the initialization signal identifying the cell allocated to the LPRM signal; a determination unit which derives at least one of amplitude and cycle of the power oscillation from the normalized value and performs determination of nuclear thermal hydraulic instability based on a predetermined algorithm; and in response to the initialization signal, the normalized value calculation unit outputs a constant value instead of the normalized value of the cell identified by the initialization signal.