Towards more reliable wind turbines: Models for gear condition monitoring

Gearbox damage can occur in different ways. The work reported here is focused on gear tooth cracking. Detailed structural models have been developed using ADAMS and ANSYS. The aim is to calculate the changes to gear train dynamic response due to cracks in individual gear teeth, and eventually through the resulting vibration signature to identify the extent and location of cracking. This last stage obviously opens up the possibility of sophisticated gear condition monitoring. It can be envisaged that suitably placed accelerometers would be used to measure changes in vibration signature and that analysis of these could be used to pinpoint the exact location and extent of damage; ie which stage of the gearbox and which type of gear. Modelling results from a suitable ADAMS model will be shown for an undamaged gearbox, with transient response and the amplitude and frequency of the important structural modes. Also detailed FE (ANSYS) modelling of a crack at different locations on the gear tooth is presented.