MONITOR FOR WATCHING REACTIVITY OF BOILING WATER REACTOR

摘要

PROBLEM TO BE SOLVED: To obtain a reactivity monitor which takes into account the density of control rods as a parameter for monitoring the reactivity of a reactor and a state of a core such as the radial and axial positions of the control rods and the output and flow rate of the core and appropriately evaluates the reactivity of the reactor from the density of the control rods. SOLUTION: By providing a device for calculating the density of the control rods to monitor reactivity which corrects the density of the control rods to the one for monitoring reactivity corresponding to the reactivity mentioned above, the difference in reactivity for one notch of the control rods made by the axial and radial positions of the control rods and the difference made by the state of the core are corrected to enable the appropriate evaluation of the reactivity with the density of the control rods.