Method for diagnosing imbalance faults of blades

Abstract

The invention discloses a method for diagnosing imbalance faults of blades. The method includes steps of (1), recording signals of current components i<q> of a quadrature axis of a generator and rotational speed signals of the generator when a wind generation set is in a running state; (2), extracting feature order components from the current components i<q> of the quadrature axis of the generator by a VKF-OT (Vold-Kalman filter order tracking) process; (3), computing an envelope spectrum of amplitudes of the feature order components; and (4), diagnosing the wind generation set according to a change condition of the envelope spectrum to determine whether the imbalance faults of the blades occur or not. The method for diagnosing the imbalance faults of the blades has the advantages that the imbalance faults of the blades of the wind generation set can be diagnosed in real time by the VKF-OT process; extra sensors or data acquisition equipment are omitted in a fault diagnosing procedure, the method is simple and feasible, and the diagnosing cost is low; non-stationary signals can be effectively processed by the VKF-OT process, so that shortcomings of the traditional signal processing technology can be overcome; and the diagnostic effectiveness, the diagnostic reliability and the diagnostic instantaneity are improved.

Description

technical field [0001] The invention relates to a fault diagnosis method for unbalanced blades, which belongs to wind power generation technology. Background technique [0002] With the increasingly serious energy crisis and environmental pollution, wind power generation has received more and more attention. All over the world, a large number of wind turbines have been put into production, which has drawn people's attention to the safe and stable operation of wind turbines. During the year-round operation of wind turbines, due to the influence of aerodynamic forces and harsh environments, wind turbines are prone to various faults. The status monitoring and fault diagnosis of wind turbines have become an indispensable link. Among them, blade imbalance fault diagnosis occurs The odds are very high. Unbalanced blades will cause huge vibration of the wind turbine, which will affect the life of the wind turbine. Wind turbine blades are expensive and difficult to maintain after...

AI Technical Summary

Problems solved by technology

[0003] At present, for the diagnosis of blade unbalance faults, relatively mature technology is based on vibration and FFT (Fast Fourier Transform, Fast Fourier Transform) analysis method, but this method has certain shortcomings

On the one hand, it is necessary to install vibration sensors on the wind turbines, which increases the cost and reduces the reliability; on the other hand, the wind speed in nature changes randomly, which will cause the vibration signals of the wind turbines to be non-stationary, and the conventional FFT does not Suitable for handling non-stationary signals

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