Gearbox diagnosis based on cyclic spectral analysis

With regards to the cyclostationarity of gear vibration, cyclic spectral analysis is used to extract the modulation features of gearbox vibration signals, so as to detect and locate localized gear damage. The cyclic spectral density of amplitude modulation and frequency modulation processes characteristic of gear vibration signals is deduced, and its properties in joint cyclic frequency-frequency domain are summarized. The performance of cyclic spectral analysis in gear fault diagnosis is illustrated by the vibration signal analysis of a gearbox under normal and faulty status. The gear tooth spalling is detected according to the presence of more peaks on the cyclic frequency-frequency plane, and is located according to the location of cyclic spectral peaks.