CN-121363518-B - State monitoring method and device for new energy wind driven generator

CN121363518BCN 121363518 BCN121363518 BCN 121363518BCN-121363518-B

Abstract

The application relates to the technical field of wind power generation, and discloses a state monitoring method and a state monitoring device for a new energy wind driven generator, which are characterized in that by analyzing the propagation delay change of sound waves in blade materials, the direct physical correlation between the sound velocity attenuation and the icing thickness is established, and the axial position of icing is directly deduced by calculating the time delay gradient ratio of different blade sections (blade tip, blade middle and blade root) and utilizing the spatial characteristics of the sound wave propagation path difference. Compared with the traditional monitoring means based on a temperature threshold value or vibration amplitude, the acoustic wave time delay is extremely sensitive to microscopic changes of a material boundary layer, and can capture micro structural changes formed in the early stage of icing.

Inventors

MA YUEMING
LI RUI
ZHANG LEPING
ZHANG DAOQUAN
KONG DETONG
ZHAO ZIXUAN
FU ZEYANG
ZHOU YUHAO
JIANG ZHIQIANG
ZHANG RUIJUN

Assignees

华电电力科学研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20251223

Claims (10)

1. A condition monitoring method for a new energy wind turbine, the method comprising: The method comprises the steps of taking a rotating speed signal at a hub as a synchronous reference, triggering a blade front edge piezoelectric exciter to output an excitation signal, and simultaneously respectively collecting acoustic wave data captured by an acoustic emission sensor under corresponding propagation paths from a blade tip, a blade middle and a blade root to a blade root; respectively extracting sound wave propagation delay for each propagation path from the blade tip, the blade middle and the blade root to the blade root, and calculating the sound wave propagation delay variation of each path in two adjacent rotation periods based on continuous rotation period data; Establishing sound velocity-icing thickness association modeling, and calculating icing position judgment coefficients according to the time delay variation of each path from the blade tip, the blade middle and the blade root to the blade root; And judging the icing state and the area according to the time delay variation of each propagation path, the time delay variation rate in the unit rotation period and the icing position judgment coefficient.
2. The state monitoring method for a new energy wind turbine according to claim 1, wherein determining the icing state and area based on the time delay variation of each propagation path, the time delay variation rate per unit rotation period, and the icing position determination coefficient, comprises: judging whether the time delay variation of each propagation path exceeds a first preset value or not and whether the time delay variation rate in a unit rotation period is larger than a second preset value or not; If the time delay variation of each propagation path exceeds a first preset value and the time delay variation rate in a unit rotation period is greater than a second preset value, judging the icing state and the area according to the relation between the icing breaking position judgment coefficient and the preset threshold value.
3. The state monitoring method for a new energy wind turbine according to claim 2, wherein determining the icing state and the area according to the relation between the icing-breaking position determination coefficient and the preset threshold value comprises: when the icing position determination coefficient is not smaller than a first threshold but smaller than a second threshold, determining that ice is present in the leaf, wherein the second threshold is larger than the first threshold; when the icing position determination coefficient is not smaller than the second threshold but smaller than a third threshold, determining that the blade tip is iced, wherein the third threshold is larger than the second threshold; And when the icing position determination coefficient is smaller than the first threshold value or not smaller than the third threshold value, determining that the blade root is iced.
4. The state monitoring method for a new energy wind turbine according to claim 2, wherein the determination of icing state and area based on the amount of time delay change of each propagation path, the time delay change rate per unit rotation period, and the icing position determination coefficient, further comprises: if the time delay variation of each propagation path does not exceed the first preset value at the same time or the time delay variation rate in the unit rotation period is not greater than the second preset value, judging that the blade state is normal.
5. The condition monitoring method for a new energy wind turbine of claim 1, further comprising: The acoustic wave data captured by the acoustic emission sensor is preprocessed.
6. The method for monitoring the state of a new energy wind turbine according to claim 5, wherein the preprocessing of the acoustic wave data captured by the acoustic emission sensor includes: performing adaptive bandpass filtering on sound wave data captured by the sound emission sensor aiming at each corresponding propagation path from the blade tip, the blade middle and the blade root to the blade root; and (3) taking a rotating speed signal at the hub as a reference, adopting a rotating speed synchronous average algorithm, aligning sound wave data of continuous preset revolutions according to a rotating angle, and then superposing and averaging.
7. The condition monitoring method for a new energy wind turbine of claim 1, further comprising: generating an icing position distribution thermodynamic diagram of the surface of the blade on the monitoring interface based on the icing judging result; when icing conditions exist in a plurality of complete rotation periods, triggering a grading early warning mechanism.
8. A condition monitoring device for a new energy wind turbine, the device comprising: The sound wave acquisition module is used for taking a rotating speed signal at the hub as a synchronous reference, triggering a blade front edge piezoelectric exciter to output an excitation signal, and respectively acquiring sound wave data captured by the sound emission sensor under corresponding propagation paths from the blade tip, the blade middle and the blade root to the blade root; the first calculation module is used for respectively extracting the acoustic wave propagation delay for each propagation path from the blade tip, the blade middle and the blade root to the blade root, and calculating the acoustic wave propagation delay variation of each path in two adjacent rotation periods based on the continuous rotation period data; the second calculation module is used for establishing sound velocity-icing thickness association modeling and calculating icing position judgment coefficients according to the time delay variation of each path from the blade tip, the blade middle and the blade root to the blade root; the state judging module is used for judging the icing state and the area according to the time delay variation of each propagation path, the time delay variation rate in the unit rotation period and the icing position judging coefficient.
9. An electronic device, comprising: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory having stored therein computer instructions, the processor executing the computer instructions to perform the condition monitoring method for a new energy wind turbine of any one of claims 1 to 7.
10. A computer-readable storage medium, characterized in that the computer-readable storage medium has stored thereon computer instructions for causing a computer to execute the condition monitoring method for a new energy wind turbine according to any one of claims 1 to 7.

Description

State monitoring method and device for new energy wind driven generator Technical Field The invention relates to the technical field of wind power generation, in particular to a state monitoring method and device for a new energy wind driven generator. Background The existing wind driven generator blade icing monitoring mainly depends on a temperature threshold method or a vibration spectrum analysis method. The vibration rule judges icing by capturing inherent frequency deviation or amplitude abnormality of the blades, but structural rigidity change caused by weak icing is easily submerged by broadband mechanical vibration noise generated by rotation of a wind wheel, and particularly, the signal to noise ratio is rapidly deteriorated under a low wind speed working condition. Both methods lack effective perceptibility for early icing, which results in delayed start of deicing system, and failure to prevent aerodynamic performance decay and structural damage risk caused by ice layer thickening. Disclosure of Invention The invention provides a state monitoring method and device for a new energy wind driven generator, which are used for solving the problem that the existing temperature threshold method and vibration spectrum analysis method lack effective perceptibility for early icing. In a first aspect, the present invention provides a method for monitoring a state of a new energy wind turbine, the method comprising: The method comprises the steps of taking a rotating speed signal at a hub as a synchronous reference, triggering a blade front edge piezoelectric exciter to output an excitation signal, and simultaneously respectively collecting acoustic wave data captured by an acoustic emission sensor under corresponding propagation paths from a blade tip, a blade middle and a blade root to a blade root; respectively extracting sound wave propagation delay for each propagation path from the blade tip, the blade middle and the blade root to the blade root, and calculating the sound wave propagation delay variation of each path in two adjacent rotation periods based on continuous rotation period data; Establishing sound velocity-icing thickness association modeling, and calculating icing position judgment coefficients according to the time delay variation of each path from the blade tip, the blade middle and the blade root to the blade root; And judging the icing state and the area according to the time delay variation of each propagation path, the time delay variation rate in the unit rotation period and the icing position judgment coefficient. The application provides a state monitoring method for a new energy wind driven generator, which establishes direct physical correlation between sound velocity attenuation and icing thickness by analyzing propagation delay change of sound waves in blade materials, and directly deduces the axial position of icing by calculating delay gradient ratio of different blade sections (blade tip, blade middle and blade root) and utilizing the spatial characteristics of sound wave propagation path difference. Compared with the traditional monitoring means based on a temperature threshold value or vibration amplitude, the acoustic wave time delay is extremely sensitive to microscopic changes of a material boundary layer, and can capture micro structural changes formed in the early stage of icing. In an alternative embodiment, determining the icing condition and the area according to the delay variation of each propagation path, the delay variation rate in the unit rotation period, and the icing position determination coefficient includes: judging whether the time delay variation of each propagation path exceeds a first preset value or not and whether the time delay variation rate in a unit rotation period is larger than a second preset value or not; If the time delay variation of each propagation path exceeds a first preset value and the time delay variation rate in a unit rotation period is greater than a second preset value, judging the icing state and the area according to the relation between the icing breaking position judgment coefficient and the preset threshold value. In an alternative embodiment, determining the icing state and the area according to the relationship between the icing breaking position determination coefficient and the preset threshold includes: when the icing position determination coefficient is not smaller than a first threshold but smaller than a second threshold, determining that ice is present in the leaf, wherein the second threshold is larger than the first threshold; when the icing position determination coefficient is not smaller than the second threshold but smaller than a third threshold, determining that the blade tip is iced, wherein the third threshold is larger than the second threshold; And when the icing position determination coefficient is smaller than the first threshold value or not smaller than the third threshold value, determining th