METHOD FOR DETECTING A BEARING DEFECT IN A ROTATING SYSTEM AND MONITORING SYSTEM IMPLEMENTING THIS METHOD

A method for detecting a defect in a bearing of a rotating system, includes acquiring a bearing position signal, a vibratory signal from the bearing and a theoretical characteristic vector of the bearing; determining a deterministic part of the vibratory signal and removing the deterministic part to obtain a residual signal function of the position signal; calculating, from the theoretical characteristic vector, lower and upper bounds of defect frequencies; calculating, from the vibratory signal, a spectral coherence and the square of the amplitude of the spectral coherence; calculating, from the square of the amplitude of the spectral coherence and the lower and upper bounds of the defect frequencies, a current characteristic vector of the bearing; determining a spectral cyclic contrast of the defect; finely identifying signatures of interest by calculating a weighted integrated cyclic coherence associated with the defect, and determining diagnostic indicators easily interpretable by an operator.