Enhanced demodulation band selection based on Operational Modal Analysis (OMA) for bearing diagnostics

TY - JOUR

T1 - Enhanced demodulation band selection based on Operational Modal Analysis (OMA) for bearing diagnostics

AU - Berntsen, Jesper

AU - Brandt, Anders

AU - Gryllias, Konstantinos

PY - 2022

Y1 - 2022

N2 - Vibration time signals emitted by a defective rolling element bearing are often used to determine its health condition. For real-world measurements these fault signals may be weak compared to the remaining content in the measured signal causing increased difficulties to fault detection. One way of enhancing the fault detection is by demodulation at a filtered frequency band in which the Signal-to-Noise-Ratio (SNR) of the fault signal is high. In the present paper, we propose a method that uses the resonances obtained from Operational Modal Analysis (OMA) as center frequencies for the filter bands as it is assumed that the characteristic bearing fault frequencies modulate resonances or carrier frequencies close to them. An indicator is used to determine which of the resonances from the OMA enhance the fault signal the most and this selection is dependent on the bandwidth as well. The presented method is applied on signals from two experimental cases, an experimental test rig of a planetary gearbox and a wind turbine gearbox, and is compared to the Fast Kurtogram and Log-Cycligram to assess its performance for band selection. The results show that the presented method determines a suited band for band pass filtering which enhances the fault detection at the two complex use cases.

AB - Vibration time signals emitted by a defective rolling element bearing are often used to determine its health condition. For real-world measurements these fault signals may be weak compared to the remaining content in the measured signal causing increased difficulties to fault detection. One way of enhancing the fault detection is by demodulation at a filtered frequency band in which the Signal-to-Noise-Ratio (SNR) of the fault signal is high. In the present paper, we propose a method that uses the resonances obtained from Operational Modal Analysis (OMA) as center frequencies for the filter bands as it is assumed that the characteristic bearing fault frequencies modulate resonances or carrier frequencies close to them. An indicator is used to determine which of the resonances from the OMA enhance the fault signal the most and this selection is dependent on the bandwidth as well. The presented method is applied on signals from two experimental cases, an experimental test rig of a planetary gearbox and a wind turbine gearbox, and is compared to the Fast Kurtogram and Log-Cycligram to assess its performance for band selection. The results show that the presented method determines a suited band for band pass filtering which enhances the fault detection at the two complex use cases.

KW - Bearing fault detection

KW - Demodulation band selection

KW - Deterministic/random separation

KW - Envelope analysis

KW - Operational modal analysis

KW - Vibration-based condition monitoring

UR - http://www.scopus.com/inward/record.url?scp=85133342878&partnerID=8YFLogxK

U2 - 10.1016/j.ymssp.2022.109300

DO - 10.1016/j.ymssp.2022.109300

M3 - Journal article

SN - 0888-3270

VL - 181

JO - Mechanical Systems and Signal Processing

JF - Mechanical Systems and Signal Processing

M1 - 109300

ER -