Interpreting vibration characteristics of planetary gearboxes for condition monitoring based on a novel transfer path effect model

Model-based vibration signal analysis can provide prior guidance for the condition monitoring and fault diagnosis of planetary gearboxes by interpreting and understanding their vibration characteristics. However, the presence of transmission path effects, caused by the rotational motion of planet gears relative to the sensor, poses challenges in accurately understanding the dynamic behaviour of planetary gearboxes. To address this issue, a novel model for the transmission path effect is proposed based on the modulation phenomenon in the planetary gearboxes. Subsequently, phenomenological models of sensor-perceived vibration signals are established for both healthy and local fault conditions, and the applicability of the proposed model to phenomenological vibration modelling is demonstrated by generating and analyzing simulated vibration signals. Finally, experimental verification on an industrial wind turbine gearbox and a test rig gearbox validates the vibration characteristics of the simulated signals obtained using our proposed model. The findings of this study showcase the potential of the proposed model in condition monitoring and fault diagnosis applications.