Abstract: Method for estimating an axial power imbalance in a nuclear reactor, comprising the following steps: obtaining a reactor power setpoint, for each variable of a plurality of variables of the reactor, determining a sequence of the variable, the sequence representing estimated future variations of the variable, determining a sequence of the axial power imbalance, by taking into account the sequences of the plurality of variables of the reactor, the determination of the sequence of the axial power imbalance using a machine learning module that is trained beforehand on historic reactor data.

Abstract: A method for restoring a partial between a peak Pi and a peak Pi+N whose frequency and phase are known. The method (1) comprises the steps of estimating (2) the frequency {circumflex over (?)} of each of the missing peaks Pi+1 to Pi+N?1 of this partial, calculating (3) the phase {circumflex over (?)} from peak to peak, from the phase of the peak Pi to that of the peak Pi+N, for all the frequencies {circumflex over (?)} previously estimated, calculating (4) the phase error err? between the calculated phase {circumflex over (?)} and the known phase at the same peak Pi+N, and correcting (5) each calculated phase {circumflex over (?)} by a value that is a function of the phase error err?.