Detecting faults in wind turbines

At least one non-transitory computer readable storage device storing instructions that, when executed by at least one processor, cause the at least one processor to perform operations comprising:

• obtaining a first signal from a generator of a wind turbine and a second signal from a vibration sensor coupled to the wind turbine, the first signal representing an output current of the generator, and the second signal being a time-sampled signal representing vibrations of a bearing in the wind turbine;
• determining a shaft rotation frequency signal from the first signal, the shaft rotation frequency signal representing a time-varying rotational speed of a shaft of the wind turbine;
• resampling an envelope of the second signal based on the shaft rotation frequency signal to provide a third signal, the third signal being an angular sampled signal, wherein resampling the envelope of the second signal comprises:
• determining, based on the shaft rotation frequency signal, a phase-time relationship between time steps of the shaft rotation frequency signal and phases of the shaft of the wind turbine, and
• generating, based on the phase-time relationship, a resampling vector of time points representing constant phase increments of the shaft of the wind turbine in an angular domain;
• and
• detecting a fault in the bearing of the wind turbine by identifying a characteristic signature of a bearing fault in the third signal.

A wind turbine generator fault detection method executed by at least one processor, the method comprising:

• obtaining a first signal from a generator of a wind turbine and a second signal from a vibration sensor coupled to the wind turbine, the first signal representing an output current of the generator, and the second signal being a time-sampled signal representing vibrations of a bearing in the wind turbine;
• determining, by the at least one processor, a shaft rotation frequency signal from the first signal, the shaft rotation frequency signal representing a time-varying rotational speed of a shaft of the wind turbine;
• resampling, by the at least one processor, an envelope of the second signal based on the shaft rotation frequency signal to provide a third signal, the third signal being an angular sampled signal, wherein resampling the envelope of the second signal comprises:
• determining, based on the shaft rotation frequency signal, a phase-time relationship between time steps of the shaft rotation frequency signal and phases of the shaft of the wind turbine, and
• generating, based on the phase-time relationship, a resampling vector of time points representing constant phase increments of the shaft of the wind turbine in an angular domain;
• and
• detecting, by the at least one processor, a fault in the bearing of the wind turbine by identifying a characteristic signature of a bearing fault in the third signal.