Method for diagnosing faults of planetary gear system of wind driven generator under variable rotating speed

Abstract

The invention relates to a method for diagnosing faults of a planetary gear system of a wind driven generator under variable rotating speed. The method for diagnosing the faults of the planetary gear system of the wind driven generator under the variable rotating speed aims to overcome defects in a method for diagnosing variable rotating speed faults in the prior art. According to the method for diagnosing the faults of the planetary gear system of the wind driven generator under the variable rotating speed, a method that order data envelopment analysis is carried out on signals is adopted, namely, input (output) shaft rotating speed signals n(t) are obtained through a rotating speed sensor, then a fitting function (please see the formula in the specification) is obtained through fitting, a function (please see the formula in the specification) of changes of rotating angles along with time is obtained through integration, a time sequence tk of equal angle resampling is obtained through an interpolation method, interpolation is carried out on accelerated speed vibration signals Y(t) through the time sequence tk to obtain equal angle resampling signals (please see the symbol in the specification), then FTP is carried out on the envelop of the equal angle resampling signals (please see the symbol in the specification), and thus an order envelop spectrum can be obtained. The problem brought by the variable rotating speed can be well solved through the order analysis, interference of noise can be well restrained through envelop analysis, and thus the order envelop method can be well applied to fault diagnosis of the planetary gear system of the wind driven generator.

Description

technical field [0001] The invention relates to the technical field of wind power generators, in particular to a fault diagnosis method for a planetary gear system of a wind power generator under variable speed. Background technique [0002] Due to the non-stationary working conditions caused by wind changes such as wind shear and turbulence, as well as frequent low-speed starts, the working speed and load of the wind power planetary gear transmission system are non-stationary and time-varying. This makes the original fault diagnosis methods based on constant speed, such as vibration analysis and spectrum analysis, not practical for fault diagnosis of actual wind turbines (such as figure 2 , 3 shown). The order analysis can well analyze the vibration signal related to the speed by sampling the signal at an equal angle, and can eliminate or reduce the influence of the speed change on the vibration signal analysis. It is a common method for fault diagnosis under variable spe...

AI Technical Summary

Problems solved by technology

In 2009, H. Li realized the fault diagnosis of fixed-axis gear system by calculating the order spectrum and order cepstrum. In 2010, J.S. Cheng realized the diagnosis of fixed-axis gear system by combining discrete wavelet signal decomposition gear system fault diagnosis, but the above fault diagnosis methods are all carried out for the fixed axis gear system

The planetary gear system has many components, complex structure, mutual coupling of vibration signals, serious low-frequency noise interference, and rich spectrum sidebands. Many fault diagnosis methods for fixed-axis gear systems cannot be applied to planetary gear systems.

[0003] Therefore, on the basis of order analysis, find out the method to deal with the signal coupling of the planetary gear system, serious noise and other problems, which will help solve the problem of variable speed in the prior art The shortcomings of diagnostic methods are of great significance

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