System for predicting desynchronization of a synchronous machine

A method for predicting and regulating desynchronization of a synchronous machine, in which a voltage detected through a voltage transformer from an armature terminal of the synchronous machine is compared with a reference voltage by a voltage deviation detector and the resulting voltage deviation performs excitation of a field winding through an automatic voltage regulator and an excitation unit, and in which a gap flux detector is installed in the synchronous machine to detect its gap flux from which a functional value of a fundamental harmonic component and/or a higher harmonic component is detected through an analyzer and the resulting functional value of the fundamental harmonic component and/or the higher harmonic component is compared with a predetermined reference level by a signal level comparator for predicting the desynchronization by detecting a shift from the reference level, the resulting detected signal for predicting the desynchronization being added through an amplifier and an adder to the voltage deviation obtained by the voltage deviation detector and then being fed to the automatic voltage regulator for regulating the excitation of the field winding.