The gear is a particularly sensitive spot in many wind turbines. Especially the gearbox has the biggest savings potential on the classic drivetrain. By consistently monitoring the components damages can be detected early.

The damage diagnosis is based on the TÜV Rheinland ISTec envelope analysis. Overall, this damage is characterized by a short escalation time. A beginning crack initialization at tooth root can be detected early and reliably only by the frequency selective envelope curve analysis. The circulation of the damaged tooth results in an intermittent excitation, which manifests itself in the rollover frequency of the gear concerned. In the signature an abrupt appearance of the rollover frequency and a formation of higher harmonic proportions can be tracked and trended. This figure shows the appearance of such signatures.