| 摘要 |
The present invention relates to a method to reduce an error in determining the shape annealing function (SAF) of an ex-core detector of a nuclear power plant, using a height constant, and a width and shape constant of the SAF based on an ex-core detector signal measured in the nuclear power plant and the SAF of the ex-core detector. The method comprises: (S1) a model forming step of modeling a core, an internal structure, a container, an external structure and an ex-core detector of a nuclear reactor; (S2) a differential cross section SAF forming step of forming, after carrying out the model forming step (S1), a differential cross section SAF_cf (z) by subtracting a value of the SAF_1 (z), which is produced from upper, middle and lower parts by applying a designed value to a neutron reaction cross section of a moderator inside a protection case of the ex-core detector, from an SAF_2 (z), which is produced from the upper, middle and lower parts by applying a half (50%) of the designed value to the neutron reaction cross section of the moderator; and (S3) a step of forming, after carrying out the differential cross section SAF forming step (S2), a least error SAF by multiplying the width and shape constant (B) of the SAF by the differential cross section SAF_cf (z), and then multiplying the total value summing up the SAF_1 (z), which is produced from the upper, middle and lower parts by applying the designed value to the neutron reaction cross section of the moderator in the protection case of the ex-core detector by the height constant (A) of the SAF. |
