Brief description of the control of the effects of reactivity due to variations of power in the top plug nuclear water pressurized

摘要

A process for controlling the reactivity effects due to the power variations in a nuclear reactor using pressurized water comprises moving movable clusters of absorbent material inside the fuel units of the reactor, the clusters comprising first sets of which at least one has an anti-reactivity of less than 700 ppht, and a second set which is composed of very absorbent clusters, the first sets being moved solely as a function of the power required of the turbine to vary the power of the reactor and the second set being moved simultaneously in dependence on the difference between the actual mean temperatures of the reactor core and a reference temperature which is a function of the level of power required.