| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for monitoring the withdrawal of control rods which decreases constraints on the operation of a reactor, and further reduces the sudden change in a thermal margin caused by an erroneous withdrawal of control rods around rated power.SOLUTION: When the reactor power P on the selection of the withdrawal of selected control rods withdrawn continuously is a set reactor power Por lower (S3) and (P+γ(a power increase limit range)) is Por lower (S5), (P+γ) is set at the maximum value (RBL' value) of a reactor power increase (S6). Since reactor power (P+γ) is reactor power P, the reactor power Pis set as the RBL' value. When S5 is "No", Pis set at the RBL's value (S7). When S3 is "Yes", (P+α(a power increase limit range)) is set at the RBL' value (S4). γ and α have the relation of γ>α. As to the selected control rods, consecutive withdrawal is continued in the relation of RBL'≤RBM (control rod withdrawal monitoring output) and consecutive withdrawal is discontinued in the relation of RBL'≤RBM. |
