CN-122021002-A - Monitoring method and device for wind turbine generator bolts, electronic equipment and storage medium

CN122021002ACN 122021002 ACN122021002 ACN 122021002ACN-122021002-A

Abstract

The invention discloses a method, a device, electronic equipment and a storage medium for monitoring a bolt of a wind turbine generator, which comprise the steps of constructing a mechanical physical model of the bolt, describing mechanical response and internal damage evolution of the bolt under the action of load, and calculating and quantifying internal plastic deformation and damage degree increase through the model. The method comprises the steps of obtaining real-time axial pretightening force, real-time axial strain and real-time load working condition data of a fan part where a bolt is located, determining current accumulated damage degree and current loosening factor of the bolt, generating an evaluation state result of the bolt according to the current accumulated damage degree and the current loosening factor, distinguishing loosening from fatigue failure, predicting the residual service life of the bolt, and carrying out early warning treatment according to the state evaluation result and/or the residual service life. The model realizes the transition from periodic maintenance to predictive maintenance based on the direct mechanical quantity and the physical law, intervenes at the optimal time point and improves the safety and the economy.

Inventors

KANG XIAOFEI
FAN XIN
ZHANG ZHOU
ZHU QIANG
LI JIANXIONG
LIU JINGJING

Assignees

中国长江三峡集团有限公司

Dates

Publication Date: 20260512
Application Date: 20260120

Claims (10)

1. The method for monitoring the bolts of the wind turbine generator is characterized by comprising the following steps of: The method comprises the steps of constructing a mechanical physical model of the bolt, wherein the mechanical physical model is used for describing mechanical response and internal damage evolution of the bolt under the action of load; Acquiring real-time axial pre-tightening force, real-time axial strain and real-time load working condition data of a fan part where the bolt is located; Determining the current accumulated damage degree and the current loosening factor of the bolt according to the real-time axial pre-tightening force, the real-time axial strain, the real-time load working condition data and the mechanical physical model; Generating an evaluation state result of the bolt according to the current accumulated damage degree and the current loosening factor, and predicting the residual service life of the bolt according to the current accumulated damage degree; And carrying out early warning processing according to the state evaluation result and/or the residual service life.
2. The method for monitoring a bolt of a wind turbine generator according to claim 1, wherein the constructing a mechanical physical model of the bolt comprises: the constitutive relation model is used for describing the relation between the axial force and deformation of the bolt under alternating load; the method comprises the steps of determining a damage evolution model of a bolt, wherein the damage evolution model is used for describing the change condition of the current accumulated damage degree along with load cycle times and time, and the current accumulated damage degree is used for quantifying the fatigue damage accumulation state in a material, and the value is 0 to 1; the loosening factor of the bolt is obtained and is used for quantifying the pretightening force efficiency loss of the bolt, and the pretightening force efficiency loss is 0 to 1; and constructing a mechanical physical model of the bolt according to the constitutive relation model of the bolt, the damage evolution model of the bolt and the loosening factor of the bolt.
3. The method for monitoring a bolt of a wind turbine generator according to claim 2, wherein the determining the constitutive relation model of the bolt comprises: Determining a constitutive relation model of the bolt according to a mixed hardening model formula combining follow-up strengthening and isotropic hardening, wherein the mixed hardening model formula is F=F (epsilon total ,ε p , alpha, Q); wherein alpha is back stress, representing follow-up reinforcement, Q is isotropic hardening saturation value, epsilon total represents total axial strain measured at a monitoring point of the bolt, epsilon p is equivalent plastic deformation, and F is axial force.
4. The method for monitoring a bolt of a wind turbine generator according to claim 2, wherein the determining the damage evolution model of the bolt comprises: Determining a damage evolution model of the bolt based on Chaboche fatigue damage theoretical formulas, wherein the fatigue damage theoretical formulas are as follows: ; wherein D is a damage variable; is equivalent plastic strain amplitude; effective stress for maximum stretching the bolt is subjected to.
5. The method for monitoring a wind turbine rotor bolt of claim 1, further comprising: Predicting the axial pretightening force and the axial strain of the next period of the bolt according to the current accumulated damage degree and the current loosening factor; Comparing the predicted axial pre-tightening force of the next period of the bolt with the axial pre-tightening force of the actual next period to obtain a first comparison result; Comparing the predicted axial strain of the next cycle of the bolt with the axial strain of the actual next cycle to obtain a second comparison result; And if the error of the first comparison result and/or the second comparison result exceeds a set threshold value, adjusting parameters of the mechanical physical model.
6. The method for monitoring a bolt of a wind turbine generator according to claim 1, wherein the generating an evaluation status result of the bolt according to the current accumulated damage degree and the current loosening factor includes: If the current accumulated damage degree is larger than the current loosening factor, generating an evaluation result of the bolt state as failure caused by fatigue damage; and if the current accumulated damage degree is smaller than the current loosening factor, generating an evaluation result of the bolt state as a failure caused by loosening.
7. The method for monitoring a bolt of a wind turbine generator according to claim 2, wherein predicting the remaining service life of the bolt according to the current accumulated damage comprises: acquiring historical load spectrum statistics and future expected load distribution; And determining the residual cycle times of the bolts based on the current accumulated damage degree, the historical load spectrum statistics, the future expected load distribution and the damage evolution model so as to predict the residual service life of the bolts.
8. A device for monitoring a wind turbine rotor bolt, comprising: The construction module is used for constructing a mechanical physical model of the bolt, wherein the mechanical physical model is used for describing the mechanical response and internal damage evolution of the bolt under the load action; the acquisition module is used for acquiring real-time axial pre-tightening force, real-time axial strain and real-time load working condition data of a fan part where the bolt is positioned; the determining module is used for determining the current accumulated damage degree and the current loosening factor of the bolt according to the real-time axial pre-tightening force, the real-time axial strain, the real-time load working condition data and the mechanical physical model; the generation and prediction module is used for generating an evaluation state result of the bolt according to the current accumulated damage degree and the current loosening factor, and predicting the residual service life of the bolt according to the current accumulated damage degree; and the early warning module is used for carrying out early warning processing according to the state evaluation result and/or the residual service life.
9. An electronic device comprising a processor, a memory and a program or instruction stored on the memory and executable on the processor, which when executed by the processor, implements the steps of the method of monitoring a wind turbine bolt according to claims 1-7.
10. A readable storage medium, characterized in that it has stored thereon a program or instructions, which when executed by a processor, implement the steps of a method for monitoring a wind turbine bolt according to claims 1-7.

Description

Monitoring method and device for wind turbine generator bolts, electronic equipment and storage medium Technical Field The invention belongs to the technical field of safe operation and maintenance of wind power generation equipment, and particularly relates to a monitoring method of a wind turbine generator bolt, a monitoring device of the wind turbine generator bolt, electronic equipment and a computer readable storage medium. Background The key bolts (such as blade root and tower flange bolts) of the wind turbine generator are subjected to complex alternating load for a long time, pretightening force relaxation and fatigue damage are easy to occur, and early failure early warning is an industrial problem. The prior art mainly comprises a static monitoring method based on a single physical quantity threshold value, an indirect diagnosis method based on a vibration signal, which is easy to be interfered by vibration of a complete machine and environmental noise, has high false alarm rate, is difficult to accurately position the damage, and an acoustic method based on the acoustic method, has high cost, is mainly qualitative, is difficult to quantify the damage degree and is insensitive to pretightening force relaxation, and early damage cannot be detected by judging the absolute value of axial force. The existing method can not realize early quantitative evaluation and residual life prediction, so that early warning is not timely, and maintenance decisions are not prospective. Disclosure of Invention The embodiment of the invention aims to provide a monitoring method for a wind turbine generator bolt, a monitoring device for the wind turbine generator bolt, electronic equipment and a corresponding computer readable storage medium, which can solve the problem of difficult early failure early warning of a key bolt of a wind turbine generator. In order to solve the technical problems, the invention is realized as follows: In a first aspect, an embodiment of the present invention provides a method for monitoring a bolt of a wind turbine, where the method includes: The method comprises the steps of constructing a mechanical physical model of the bolt, wherein the mechanical physical model is used for describing mechanical response and internal damage evolution of the bolt under the action of load; Acquiring real-time axial pre-tightening force, real-time axial strain and real-time load working condition data of a fan part where the bolt is located; Determining the current accumulated damage degree and the current loosening factor of the bolt according to the real-time axial pre-tightening force, the real-time axial strain, the real-time load working condition data and the mechanical physical model; Generating an evaluation state result of the bolt according to the current accumulated damage degree and the current loosening factor, and predicting the residual service life of the bolt according to the current accumulated damage degree; And carrying out early warning processing according to the state evaluation result and/or the residual service life. Optionally, the constructing a mechanical physical model of the bolt includes: the constitutive relation model is used for describing the relation between the axial force and deformation of the bolt under alternating load; the method comprises the steps of determining a damage evolution model of a bolt, wherein the damage evolution model is used for describing the change condition of the current accumulated damage degree along with load cycle times and time, and the current accumulated damage degree is used for quantifying the fatigue damage accumulation state in a material, and the value is 0 to 1; the loosening factor of the bolt is obtained and is used for quantifying the pretightening force efficiency loss of the bolt, and the pretightening force efficiency loss is 0 to 1; and constructing a mechanical physical model of the bolt according to the constitutive relation model of the bolt, the damage evolution model of the bolt and the loosening factor of the bolt. Optionally, the determining the constitutive relation model of the bolt includes: Determining a constitutive relation model of the bolt according to a mixed hardening model formula combining follow-up strengthening and isotropic hardening, wherein the mixed hardening model formula is F=F (epsilon total,εp, alpha, Q); wherein alpha is back stress, representing follow-up reinforcement, Q is isotropic hardening saturation value, epsilon total represents total axial strain measured at a monitoring point of the bolt, epsilon p is equivalent plastic deformation, and F is axial force. Optionally, the determining the damage evolution model of the bolt includes: Determining a damage evolution model of the bolt based on Chaboche fatigue damage theoretical formulas, wherein the fatigue damage theoretical formulas are as follows: ; wherein D is a damage variable; is equivalent plastic strain amplitude; effective str