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Vol.5 , No. 1, Publication Date: Jan. 11, 2018, Page: 9-14
 were removed from the vibration data by converting the time domain signal into the order domain. Results show that the carrier frequency is not necessarily one of bearing’s natural frequencies. Out of two main frequency bands excited due to the fault, one included a structural frequency, however the other frequency band did not.&picture=http://www.aascit.org/aascit/decorators/img/journal/925.jpg)
| [1] | Ehsan Mollasalehi, Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, Alberta, Canada. |
The objective of this paper is to contribute to the understanding of the bearing carrier frequency. It is widely believed that the carrier frequency of modulating fault frequencies is typically one of the bearing’s natural frequencies. To verify this assumption, Operational modal analysis was performed on the bearing vibration signals. Operational modal analysis main assumption is that the excitation of the structure is white Gaussian, which is violated in operating machines. Therefore, the harmonics (shaft and fault harmonics) were removed from the vibration data by converting the time domain signal into the order domain. Results show that the carrier frequency is not necessarily one of bearing’s natural frequencies. Out of two main frequency bands excited due to the fault, one included a structural frequency, however the other frequency band did not.
Keywords
Bearing Carrier Frequency, Amplitude Demodulation, Envelope Analysis, Wind Turbine, Condition Monitoring, Fault Diagnosis
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