| With the increase of power capacity of wind turbines and wind farms, the wind-powered electricity accounts for a higher percentage in energy structure. The reliability of large anemo-electric generators becomes more important for the safe running of power systems. If they break down seriously, power systems may collapse, which will cause heavy loss to our state. What's more, as the national policy for the power plants is implemented gradually, the generating cost has become one of critical factors for the plants'survival. Through diagnosing the high fault-rate wind generators and taking measures that coordinate the planning maintenance and the condition-based maintenance, wind farms can reduce the generating cost greatly and improve their competitive ability largely. So the research for the diagnosis technology of wind generators'faults is very instant and essential.According to the fact of wind-powered electricity industry of our country, the thesis has summarized the backgrounds, meanings, research status and development directions of state monitoring and faults diagnosis for anemo-electric generators and exposited the research status and important meanings of time series analysis. Based on the fault mechanism, the paper has analysed electrical characteristics and mechanical characteristics of anemo-electric generators under fault states. Then it has indicated features of stator current signal and rotor vibration signal and studied the time series model, the methods of parameters estimation and best prediction mainly.Aiming at rotor broken-bar fault of anemo-electric generators, the thesis has performed an experiment practically. Real-time stator current signal and rotor vibration signal have been acquired under normal states and fault states and processed with Fourier Transform. Then the paper has built the time series model of fault diagnosis and predicted the working state of the wind generator. The experiment proved practicability and effectiveness of this method.
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