Frequency Response Analysis for Rolling-Bearing Damage Diagnosis

This paper deals with a new diagnosis method for detecting bearing faults (BFs) based on frequency response analysis. For non-rigid multi-mass systems with dominant mechanical resonance frequencies, the frequency response has to be calculated during the commissioning of the plant for reasons of safety and controlling. This task can be achieved by measuring two control variables of the drive which are both affected by BFs. This paper proposes that the measurement of the frequency response is a suitable strategy for detecting incipient BFs. In doing so, a two-channel analysis method for bearing damage diagnosis without additional sensors is developed. Deviations from the frequency response of the healthy state serve as indicators for a present BF. As the measurement of the two signals can be carried out during normal operation of the plant, online BF diagnosis is achieved. For the investigated two-inertia system, single-point bearing defects on the inner and outer raceways of rolling bearings and generalized roughness faults are within the scope of this paper.