Method and system for combined monitoring of wind turbine status

Abstract

The invention discloses a fan state combined monitoring method and system. The method comprises the following steps: calculating a standard time domain signal under each working condition state of a fan; performing synchronous compression wavelet transform on the standard time domain signal to obtain a corresponding standard three-dimensional time-frequency spectrum diagram; collecting a fan real-time vibration signal, and performing synchronous compression wavelet transform on the real-time vibration signal to obtain a real-time three-dimensional time-frequency spectrum diagram; interceptinga time period to be monitored and the corresponding characteristic frequency band in the real-time three-dimensional time-frequency spectrum diagram to generate each intercepted time-frequency spectrum diagram; performing inverse synchronous compression wavelet transform on each intercepted time-frequency spectrum diagram to obtain a time-domain signal of real-time vibration signal sub-components;and calculating a first correlation coefficient, a second correlation coefficient and a third correlation coefficient between the time-domain signal of the real-time vibration signal sub-components and the standard time domain signal under each working condition state, and judging the state of the fan according to the third correlation coefficient. The operating state of the fan is accurately judged, and the processing efficiency is high.

Description

technical field [0001] The invention relates to the field of signal processing, in particular to a method and system for combined monitoring of fan status. Background technique [0002] As the running time increases, the dust in the fan will adhere to the impeller unevenly, gradually destroying the dynamic balance of the fan, and gradually increasing the vibration of the bearing. Once the vibration reaches the maximum value allowed by the fan, the fan must be shut down for repair. The annual loss of power generation due to wind turbine failure and the maintenance costs caused by the failure have brought huge economic losses to wind farms. In terms of reducing maintenance time and cost, timely assessment of fan status is very necessary. [0003] At present, the fan state judgment methods based on the fan vibration signal are mainly time-domain methods and frequency-domain methods. The time-domain method mainly intercepts a period of vibration time-domain signal, and then ca...

AI Technical Summary

Problems solved by technology

[0005] Although the above-mentioned patent application can identify and judge the operating state of the fan, it is based on the analysis of the frequency component information and the main modulation frequency information of the vibration signal. When the frequency information is similar but the time trend is completely different, it will still be mistaken for belong to the same fan operating state

In addition, the above application obtains the subcomponents of the vibration signal of the axial flow fan through fast Fourier transform, but the processing process is complicated, and it cannot take into account the requirements of frequency and time resolution

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