Fan tower drum fault diagnosis method, storage medium and program product

Abstract

The invention relates to the field of wind power equipment monitoring, and discloses a fan tower drum fault diagnosis method, a storage medium and a program product. The method comprises the following steps: synchronously acquiring vibration signals through an acceleration sensor array, separating inherent frequencies and vibration mode vectors of first m-order modals, constructing modal flexibility matrixes of all orders based on a mass normalization condition, superposing the modal flexibility matrixes to form an integral flexibility matrix Fmodal, and calculating the deviation degree of Fmodal elements relative to a finite element reference flexibility matrix, so as to obtain the flexibility of the first m-order modals. And accurate positioning and classification of flange plate bolt pre-tightening force attenuation, crack propagation and cylinder instability faults are realized according to the grading threshold values. The problem of missed judgment caused by the fact that a traditional method depends on single-mode parameters is solved, and the early-stage fault detection rate is remarkably increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of wind power equipment state monitoring technology, and particularly relates to a wind turbine tower flange damage diagnosis method based on vibration modal analysis. BACKGROUND

[0002] The wind turbine tower is connected through high-strength bolts, and is prone to pre-tightening force attenuation and loosening under long-term alternating loads, leading to structural instability and even collapse. Traditional detection relies on manual knocking or torque wrench regular inspection, which is low in efficiency, high in cost, and unable to provide real-time early warning. SUMMARY

[0003] In view of the technical defects and technical disadvantages in the prior art, the embodiments of the present application provide a wind turbine tower fault diagnosis method, a storage medium and a program product which overcome the above problems or at least partially solve the above problems, and the specific schemes are as follows: As a first aspect of the present application, a wind turbine tower fault diagnosis method is provided, comprising the following steps: S1, arranging an acceleration sensor array at each level flange of the tower, and acquiring time-domain vibration signals of each level flange position through synchronous sampling; S2, separating the natural frequencies of the first m dominant sway modes from the time-domain vibration signals f k and the corresponding spatial mode vectors φ k wherein k=1, 2,..., m represents the mode order index; S3, converting the natural frequencies f k into angular frequencies ω k , generating the modal flexibility matrix of each mode through the formula based on the mass normalization condition; S4, superimposing the first m modal flexibility matrices to construct the overall structure flexibility matrix ; S5, calculating the deviation degree of each element in F modal relative to the corresponding elements of the finite element reference flexibility matrix F FE , and positioning the fault flange level and determining the fault type according to the preset damage diagnosis threshold.

[0004] Further, m=3, and in step S2, the natural frequencies of the first 3 dominant sway modes are separated from the time-domain vibration signals f k and the spatial mode vectors φ k , and specifically comprising: Taking the frequency zero time point in the time domain vibration signal as a segmentation point, the continuous signal is divided into discrete sections, sections with a time length less than a preset threshold G are removed, and a set of valid analysis sections is retained; For each valid section S (i) , a modal cascade judgment is performed, including: When a sway frequency ∈ [0.7F1, 1.3F1] and a power value > a corresponding power threshold are detected, it is marked as a first-order sway frequency; when a sway frequency ∈ [0.7F2, 1.3F2] and a power value > a corresponding power threshold are detected, it is marked as a second-order sway frequency; when a sway frequency ∈ [0.7F3, 1.3F3] and a power value > a corresponding power threshold are detected, it is marked as a third-order sway frequency, where F1, F2 and F3 are the first-order, second-order and third-order simulation natural frequencies of the fan tower, respectively; The marked results are aggregated across sections, respectively, including: calculating the arithmetic mean of all first-order sway frequencies to obtain the natural frequency f 1 ; calculating the arithmetic mean of all second-order sway frequency sets to obtain the natural frequency f 2 ; and calculating the arithmetic mean of all third-order sway frequencies to obtain the natural frequency f 3 ; For each mode k ∈ {1, 2, 3}: calculate the correlation coefficient of the measured spatial mode shape vector of each valid section and the simulation reference mode shape of the order, and select the measured spatial mode shape vector with the maximum correlation coefficient as the final spatial mode shape vector of the corresponding order mode φ k .

[0005] Further, in step S2, the natural frequencies of the first three dominant sway modes f k and spatial mode shape vectors φ k are separated from the time domain vibration signal; in S3, the mass normalization condition is realized by setting the modal mass m(k) = 1, so that the modal stiffness k(k) = m(k) ω k 2 = ω k 2 , so that , in S4, the first three order modal flexibility matrices are superimposed to construct the overall structure flexibility matrix .

[0006] Further, the acceleration sensor array in step S1 is arranged to satisfy the following technical constraints: The hierarchical mapping relationship: the number of acceleration sensors is equal to the number of flange disc levels of the fan tower, and each sensor is installed in the sensitive area of the geometric feature at the top of the corresponding flange disc, and a mapping relationship between the sensor index and the spatial position of the flange disc level is established; Dynamic acquisition performance: all sensors work in a synchronous sampling mode, and the sampling frequency is significantly higher than the highest modal frequency of the tower Structural coverage completeness: through the synergistic effect of the hierarchical mapping relationship and the dynamic acquisition performance, it is ensured that the spatial resolution of the measured mode shape data covers all flange connection weak areas.

[0007] Further, the calculation F modal The deviation of each element with respect to the finite element reference flexibility matrix F FE The deviation of the corresponding element, including: The flexibility matrix obtained by finite element simulation is taken as the reference flexibility matrix F FE The element F FE (i,n) represents the reference displacement response of the unit force at the top of the tower at the i-th flange disc level; The element F modal is extracted from the total flexibility matrix F FE (i,n) The element F modal ( i,n ), which represents the measured displacement response of the unit force at the top of the tower at the i-th flange disc level; The displacement response deviation is calculated item by item according to the hierarchical index i=1,2,…,n: .

[0008] Further, according to the preset damage diagnosis threshold, the fault flange disc level is located and the fault type is determined, including: When 5%≤ΔF(i,n)<15%, it is determined that the i-th flange disc bolt pre-tightening force attenuation fault; When 15%≤ΔF(i,n)<25%, it is determined that the i-th flange disc crack propagation fault; When ΔF(i,n)≥25%, it is determined that the i-th flange disc cylinder local failure stress fault.

[0009] Further, the reference flexibility matrix in S5 is generated by a finite element simulation process, including: A three-dimensional parametric finite element model is established based on the design parameters of the fan tower, including the geometric features of the flange disc and the bolt connection contact pair; Boundary constraints and load spectrum consistent with the measured working condition are applied in the model; An axial pressure load spectrum is applied on the model, and each order eigenvalue modal analysis is carried out, and simulation modal parameters are output, including simulation natural frequency F k And simulation reference mode Φ k ; The simulation modal parameters are substituted into the flexibility matrix synthesis formula:

[0010] The reference flexibility matrix with the same dimension as F modal is obtained.

[0011] As a second aspect of the present application, a computer readable storage medium is provided, characterized in that the computer readable storage medium stores a computer program, and the computer program, when executed by a computer, causes the computer to perform the fan tower failure diagnosis method of any of the above.

[0012] As a third aspect of the present application, a computer program product is provided, comprising computer readable code, or a non-volatile computer readable storage medium carrying computer readable code, when the computer readable code is executed in the processor of an electronic device, the processor in the electronic device performs the fan tower failure diagnosis method of any of the above.

[0013] The present application has the following beneficial effects: The present application adopts multiple acceleration sensors, each of which is installed at each flange plate of the fan tower, and uses multi-dimensional sensor data to calculate the flexibility matrix of the fan tower, and compares the real-time calculated flexibility matrix with the finite element simulation result to detect the failure of each layer flange plate. The present application can quantitatively analyze the failure more finely, and is not disturbed by the environment in vibration. The failure includes bolt loosening, crack, metal fatigue failure, etc. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 A flowchart of a fan tower failure diagnosis method provided by the embodiment of the present application. DETAILED DESCRIPTION

[0015] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0016] To enable those skilled in the art to better understand the technical solutions of the present invention, exemplary embodiments of the present invention are described below in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0017] Where there is no conflict, the various embodiments of the present invention and the features thereof may be combined with each other.

[0018] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0019] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0020] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly so defined herein.

[0021] In the technical solution of this invention, the collection, storage, use, processing, transmission, provision, and disclosure of user personal information all comply with relevant laws and regulations and do not violate public order and good morals. The use of user data in this technical solution follows relevant national laws and regulations (e.g., the "Information Security Technology - Personal Information Security Specification"). For example: appropriate measures are taken for personal information access control; restrictions are imposed on the display of personal information; the purpose of using personal information does not exceed the scope of direct or reasonable association; and explicit identity targeting is eliminated when using personal information to avoid precisely locating a specific individual.

[0022] To address at least one of the technical problems existing in the aforementioned related technologies, the present invention provides a method for diagnosing wind turbine tower faults. Figure 1 A flowchart illustrating a wind turbine tower fault diagnosis method provided in this embodiment of the invention includes the following steps: S1, accelerometer arrays are installed at the flanges of each level of the tower, and the time-domain vibration signals of each flange position are obtained through synchronous sampling; S2, for the time-domain vibration signals of each flange position collected, separate the natural frequencies of the first m dominant sway modes from the time-domain vibration signals. f k With spatial mode vector φ k Where k=1,2,…,m represents the modal order index; S3, the natural frequency f k Convert to angular frequency ω k Based on the quality normalization condition, through the formula Generate modal compliance matrices sequentially; S4, superimpose the first m-order modal compliance matrices to construct the overall structural compliance matrix. ; S5, Calculation F modal Each element in the model has a relative compliance matrix with respect to the finite element reference matrix. F FE The deviation of the corresponding element is used to locate the fault flange level and determine the fault type based on the preset damage diagnosis threshold.

[0023] This invention establishes a standardized fault diagnosis framework through a complete process from vibration signal acquisition to compliance matrix construction, avoiding the limitations of traditional methods that rely on a single vibration parameter. It utilizes the modal compliance matrix (… F modal High sensitivity to local damage (even minor damage can cause a significant deviation in compliance value), improving the early fault detection rate; superimposed compliance matrix of the first m dominant modes ( This comprehensively reflects the overall stiffness characteristics of the structure, overcomes the one-sidedness of single-order modal analysis, and achieves multimodal fusion.

[0024] In some embodiments, only the first three dominant modes are typically considered, and the contribution of higher-order modes to the compliance is small and can be ignored. Therefore, in this embodiment of the invention, m=3, and in step S2, the natural frequencies of the first three dominant swaying modes are separated from the time-domain vibration signal. f k With spatial mode vector φ k Specifically, it includes: Using the moment when the frequency of the vibration signal returns to zero as the dividing point, the continuous signal is divided into discrete segments. Segments with a duration less than a preset threshold G are removed, and the set of valid analysis segments is retained. For each valid segment S (i) The oscillation spectrum is used to perform modal cascade judgment, including: When a swaying frequency ∈ [0.7F1, 1.3F1] is detected and the power value is greater than the corresponding power threshold, it is marked as a first-order swaying frequency; when a swaying frequency ∈ [0.7F2, 1.3F2] is detected and the power value is greater than the corresponding power threshold, it is marked as a second-order swaying frequency; when a swaying frequency ∈ [0.7F3, 1.3F3] is detected and the power value is greater than the corresponding power threshold, it is marked as a third-order swaying frequency, where F1, F2, and F3 are the first-order, second-order, and third-order finite element simulation natural frequencies of the wind turbine tower, respectively. The labeled results are aggregated across segments, including: calculating the arithmetic mean of all first-order sway frequencies to obtain the natural frequencies. f 1 The natural frequency is obtained by taking the arithmetic mean of all second-order wobbling frequencies. f 2 The natural frequency is obtained by taking the arithmetic mean of all third-order wobbling frequencies. f 3 ; For each mode k∈{1,2,3}: calculate the correlation coefficient between the measured spatial mode shape vector of each effective segment and the simulation reference mode shape of that order, and select the measured spatial mode shape vector with the maximum correlation coefficient as the final spatial mode shape vector of the corresponding mode. φ k .

[0025] In the above embodiments, the signal is segmented at the "frequency zeroing moment" and short-time segments (<threshold G) are eliminated to effectively remove the influence of transient interference. Combined with the dual criteria of frequency bandwidth (±30% of the simulation value) and power threshold, misjudgments caused by noise or harmonics are avoided. Random errors are suppressed by arithmetically averaging the natural frequency across segments, and the mode shape vector is matched to the simulation benchmark through the correlation coefficient to ensure the spatial accuracy of the mode shape.

[0026] In some embodiments, in step S2, the natural frequencies of the first three dominant sway modes are separated from the time-domain vibration signal. f k With spatial mode vector φ k In S3, the mass normalization condition is set by adjusting the modal mass. m(k) =1 is achieved, which makes the modal stiffness k(k) = m(k) ω k 2 = ωk 2 Thus obtain In S4, the first three modal compliance matrices are superimposed to construct the overall structural compliance matrix. .

[0027] In the above embodiments, m=3 (the first three dominant modes) is limited to balance computational efficiency and diagnostic accuracy, and to adapt to the low-order sway characteristics of wind turbine towers.

[0028] In some embodiments, the accelerometer array layout in step S1 meets the following technical constraints: Hierarchical mapping relationship: The number of acceleration sensors is equal to the number of layers of the wind turbine tower flange, and each sensor is installed in the geometric feature sensitive area on the top of the corresponding flange, and a spatial position mapping relationship between the sensor index and the flange layer is established. Dynamic acquisition performance: All sensors operate in a synchronous sampling mode, with a sampling frequency significantly higher than the tower's highest mode of interest frequency. Structural coverage completeness: Through the synergistic effect of the hierarchical mapping relationship and dynamic acquisition performance, the spatial resolution of the measured vibration mode data is ensured to cover all weak areas of the flange connection.

[0029] In the above embodiments, the sensors correspond one-to-one with the flange layers to ensure that the mode shape data covers all weak areas; local deformation signals are captured by deploying geometrically sensitive areas; all sensors sample synchronously at frequencies higher than the highest mode of interest to avoid mode shape distortion caused by phase differences.

[0030] In some embodiments, calculation F modal Each element in the model has a relative compliance matrix with respect to the finite element reference matrix. F FE The deviation of the corresponding element includes: The compliance matrix obtained from finite element simulation is used as the reference compliance matrix. F FE Its elements F FE (i,n) This represents the reference displacement response generated at the i-th layer flange by a unit force at the top of the tower; From the overall softness matrix F modal Extracting and F FE (i,n) Elements at the same position F modal ( i,n This element characterizes the measured displacement response generated by a unit force at the top of the tower at the i-th layer flange; Calculate the displacement response deviation item by item according to the hierarchical index i=1,2,…,n: .

[0031] In the above embodiments, the compliance matrix elements are defined. F modal ( i,n The displacement response of the flange at the i-th layer is directly related to the layer position, and is achieved through... Quantify the deviation to achieve damage level localization, and use the finite element simulation compliance matrix ( F FE Using this as a benchmark, the influence of individual differences in design parameters is eliminated.

[0032] In some embodiments, locating the faulty flange level and determining the fault type based on a preset damage diagnosis threshold includes: When 5%≤ΔF(i,n)<15%, the fault is determined to be the preload reduction of the flange bolts of the i-th layer. When 15%≤ΔF(i,n)<25%, the crack propagation fault of the i-th layer flange is determined. When ΔF(i,n)≥25%, the local failure stress fault of the i-th layer flange cylinder is determined.

[0033] In the above embodiments, the fault type and severity are determined simultaneously by using three threshold levels: preload attenuation (5%≤ΔF<15%), crack propagation (15%≤ΔF<25%), and local instability (ΔF≥25%). The reliability of operation and maintenance decisions (such as preload re-inspection, shutdown maintenance, etc.) is improved by quantifying the thresholds.

[0034] In some embodiments, the reference compliance matrix in S5 is generated through a finite element simulation process, including: A three-dimensional parametric finite element model was established based on the design parameters of the wind turbine tower, including the geometric features of the flange and the bolt connection contact pairs; The model is subjected to boundary constraints and load spectra consistent with the actual operating conditions, including: fixed constraints at the tower base, aerodynamic thrust load of the wind turbine, and torque fluctuation spectrum of the generator. An axial pressure load spectrum (simulating the tower's self-weight and the wind turbine's thrust) is applied to the model, and eigenvalue modal analysis of each order is performed. The simulation modal parameters, including the simulation natural frequencies, are output. F k and simulation reference mode shape Φ k ; Substitute the simulation modal parameters into the compliance matrix synthesis formula:

[0035] Obtain and F modal A baseline compliance matrix of the same dimension.

[0036] In some embodiments, S5 further includes generating a fault spatial distribution map, specifically including: The total height of the tower is divided equally according to the number of flange levels, defining a sequence of height points from the bottom to the top of the tower. h 1 , h 2 ,…, h n The bottom flange corresponds to the reference height point at the bottom of the tower, the top flange corresponds to the reference height point at the top of the tower, and the flanges of each intermediate layer are mapped to their corresponding height points proportionally. From the measured compliance matrix F modal Extract all elements from the last column to form the measured displacement response sequence under a unit force at the top of the tower. F modal (1,n), F modal (2,n),…, F modal (n,n)] T From the baseline compliance matrix F FE Extract column elements at the same position to form a reference displacement response sequence. F FE (1,n), F FE (2,n),…, F FE (n,n)] T ; For each elevation point h i Displacement response data: Calculate the absolute difference between the measured displacement and the reference displacement: Deviation = | F modal (i,n)- F FE (i,n)∣, divide the difference by the baseline value at that point and convert it to a percentage form, the rate of change i = (deviation / F) FE (i,n))×100%, thus obtaining the distribution sequence of the compliance rate of change along the tower height ΔC=[rate of change 1, rate of change 2,…, rate of change n]; Based on height point sequence [ h 1 , h 2 ,…, h n ] and rate of change series ΔC A cubic spline interpolation algorithm is used for curve fitting to generate a gradient curve of the compliance rate of change that is continuously distributed along the height of the tower.G(h) ; Identify gradient curves G(h) All local maxima points ( G(h) >Points with a significance threshold are considered local maxima. For each local maximum point hpeak Calculate the distance to the nearest flange. d =min(∣ hpeak- hi∣); like d ≤ Positioning tolerance (d default 0.05H), mapped to the nearest flange level; like d >Positioning tolerance, marked as a cylinder section fault; The final output includes two types of fault location information: the flange level number where the fault occurred and the precise height coordinates of the cylinder section fault.

[0037] In the above embodiments, the model includes flange bolt contact pairs to accurately simulate connection stiffness; The load spectrum covers the wind turbine thrust and torque fluctuations, closely matching actual working conditions; the output simulated vibration modes are used for mode correlation verification, improving the reliability of measured parameters.

[0038] This invention also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps of any of the wind turbine tower fault diagnosis methods described in the above embodiments. The computer-readable storage medium may be volatile or non-volatile.

[0039] This invention also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code. When the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described wind turbine tower fault diagnosis method.

[0040] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0041] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0042] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0043] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the computer-readable program instructions. This electronic circuitry can execute the computer-readable program instructions to implement various aspects of the invention.

[0044] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0045] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0046] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0047] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0048] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction, which contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0049] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wind turbine tower failure diagnosis method characterized by, Comprising the following steps: S1, arranging an acceleration sensor array at each level flange plate of the tower drum, and acquiring time-domain vibration signals of each level flange plate position by synchronous sampling; S2, separating the inherent frequency of the first m-order dominant sway mode from the time-domain vibration signal f k a spatial mode shape vector corresponding thereto φ k wherein k = 1, 2, …, m represents a mode order index; S3, the natural frequency f k Convert to angular frequency ω k Based on the mass normalization condition, through the formula Generate each modal flexibility matrix step by step; S4, superimpose the m order modal flexibility matrix before stacking, construct the overall structure flexibility matrix ; S5, calculating F modal the element relative to the finite element reference flexibility matrix F FE the deviation of the corresponding element, and positioning the fault flange level and determining the fault type according to the preset damage diagnosis threshold.

2. The fan tower failure diagnostic method of claim 1, wherein m=3, in step S2, the natural frequencies of the first three dominant sway modes are separated from the time-domain vibration signal f k with the spatial mode shape vector φ k , specifically comprising: Divide the continuous signal into discrete segments with the frequency zero time point in the time-domain vibration signal as the division point, eliminate the segments with a time length less than a preset threshold G, and retain the effective analysis segment set; for each valid segment S (i) a shaking spectrum, performing a modal cascade determination, comprising: When the sway frequency ∈ [0.7F1, 1.3F1] and the power value > the corresponding power threshold are detected, it is marked as a first-order sway frequency; when the sway frequency ∈ [0.7F2, 1.3F2] and the power value > the corresponding power threshold are detected, it is marked as a second-order sway frequency; when the sway frequency ∈ [0.7F3, 1.3F3] and the power value > the corresponding power threshold are detected, it is marked as a third-order sway frequency, wherein F1, F2 and F3 are the first-order, second-order and third-order simulation natural frequencies of the fan tower drum, respectively; respectively, including: calculating the arithmetic mean of all first-order sway frequencies to obtain the natural frequency f 1 ; calculating the arithmetic mean of all second-order sway frequency sets to obtain the natural frequency f 2 ; calculating the arithmetic mean of all third-order sway frequencies to obtain the natural frequency f 3 ; For each order modal k∈{1,2,3}: calculate the correlation coefficient of the measured space mode vector of each effective section and the simulation reference mode of the order, select the measured space mode vector with the maximum correlation coefficient as the final space mode vector of the corresponding order modal φ k .

3. The method of claim 1, wherein, In step S2, the natural frequencies of the first three dominant sway modes are separated from the time-domain vibration signal f k and the spatial mode shape vector φ k In step S3, the mass normalization condition is achieved by setting the modal mass m(k) =1, so that the modal stiffness k(k)=m(k)ω k 2 = ω k 2 , so as to obtain In step S4, the first three modal flexibility matrices are superimposed to construct the overall structure flexibility matrix .

4. The method of claim 1, wherein, The acceleration sensor array in step S1 meets the following technical constraints: Level mapping relationship: the number of acceleration sensors is equal to the number of flange plate levels of the fan tower drum, and each sensor is installed in the geometric feature sensitive area on the top of the corresponding flange plate, and a spatial position mapping relationship between the sensor index and the flange plate level is established; Dynamic acquisition performance: all sensors work in a synchronous sampling mode, and the sampling frequency is significantly higher than the highest concerned modal frequency of the tower drum Structural coverage completeness: through the synergistic effect of the level mapping relationship and the dynamic acquisition performance, the spatial resolution of the measured mode shape data covers all flange connection weak areas.

5. The method of claim 1, wherein, Computing F modal the element relative to the finite element basis flexibility matrix F FE the deviation of the corresponding element, comprising: The flexibility matrix obtained from the finite element simulation is taken as the reference flexibility matrix F FE the elements of which F FE (i,n) denotes the reference displacement response at the flange of the i-th level generated by the unit force at the top of the tower; from the total flexibility matrix F modal extracted from the total flexibility matrix F FE (i,n) elements in the same position F modal i,n , which element represents the measured displacement response at the flange of the i-th level produced by a unit force at the top of the tower.​ Calculate the displacement response deviation degree item by item according to the level index i=1, 2, …, n: 。 6. The method of claim 1, wherein, According to the preset damage diagnosis threshold, locate the fault flange plate level and determine the fault type, including: When 5%≤ΔF(i,n)<15%, it is determined that the bolt pre-tightening force of the i-th layer flange plate is attenuated; When 15%≤ΔF(i,n)<25%, it is determined that the i-th layer flange plate has a crack propagation fault; When ΔF(i,n)≥25%, it is determined that the i-th layer flange plate has a local failure stress fault where ΔF(i, n) is F modal the element relative to the finite element reference flexibility matrix F FE the deviation of the corresponding element.

7. The method of claim 1, wherein, The reference flexibility matrix in S5 is generated by a finite element simulation process, including: Based on the design parameters of the fan tower drum, a three-dimensional parameterized finite element model is established, including the geometric features of the flange plate and the bolt connection contact pair; In the model, the boundary constraints and load spectrum consistent with the measured working conditions are applied; Apply axial compression load spectrum on the model, conduct eigenvalue modal analysis of each order, output simulation modal parameters, including simulation natural frequency F k and simulation reference mode shape Φ k ; Substitute the simulation modal parameters into the flexibility matrix synthesis formula: ； obtained with F modal a reference flexibility matrix of the same dimension.

8. A computer-readable storage medium, characterized in that, The computer readable storage medium stores a computer program, and the computer program is executed by a computer to perform the fan tower drum fault diagnosis method according to any one of claims 1 to 7.

9. A computer program product comprising computer readable code, or a non-volatile computer readable storage medium carrying computer readable code, when the computer readable code is executed in the processor of an electronic device, the processor in the electronic device performs the fan tower drum fault diagnosis method according to any one of claims 1 to 7.

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