Blade damage identification method, device and medium based on continuous wavelet transform

Abstract

The present invention discloses a blade damage identification method, device and medium based on continuous wavelet transform, the method comprising: constructing a finite element model of a composite beam; obtaining an undamaged modal vibration mode and a damaged modal vibration mode of the finite element model; performing boundary amplification processing on the first-order derivatives of the undamaged modal vibration mode and the damaged modal vibration mode to eliminate the boundary effect of the undamaged modal vibration mode and the damaged modal vibration mode; performing continuous wavelet transform processing on the first-order derivative after boundary amplification processing to obtain a damage identification result; obtaining the wavelet peak position and wavelet peak size of different degrees of damage; and locating and quantifying damage according to the wavelet peak position and the wavelet peak size. The present invention can improve the accuracy of damage identification and can be widely used in the field of data processing technology.

Description

Technical Field

[0001] The invention relates to the technical field of data processing, and in particular to a blade damage identification method, device and medium based on continuous wavelet transform. Background Art

[0002] Wind power generation refers to the conversion of wind kinetic energy into electrical energy. Wind energy is a clean and pollution-free renewable energy that has been used by people for a long time. It is very environmentally friendly to use wind power for power generation, and the wind energy reserves are huge. Therefore, it is increasingly valued by countries around the world. As one of the core components of wind turbines, blades have a high failure rate, and accidents such as blade damage and breakage are also common, which directly affects the level of power generation and indirectly affects the economic and social benefits. The method of repairing the composite wind turbine blade structure by staggered laying of fiber cloth can effectively inhibit the expansion of existing damage and improve the service life and safety of the structure. Compared with the traditional riveting repair technology, the technology of repairing composite materials by staggered laying of fiber cloth has the characteristics of stable stress transmission and avoidance of additional stress concentration, and has excellent fatigue and damage tolerance performance. At the same time, it is easy to construct on the curved surface of the wind turbine blade structure. However, the blade repair structure still has a high risk of damage during long-term service, and delamination and debonding damage are the main damage modes of the composite repair part. When the damage in the blade repair area is found, there are often obvious cracks on the outside, and at this time, the inside has been seriously damaged, which is very likely to cause the blade to be scrapped and cause great economic losses.

[0003] In order to avoid the above situation, it is necessary to conduct real-time working status monitoring, damage monitoring and remaining life estimation of the wind turbine blade repair area to predict alarm failures, ensure the blade life, and thus improve the overall reliability of the wind turbine. In the process of damage identification for composite blades in the existing technology, there are problems such as low damage identification accuracy. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides a blade damage identification method, device and medium based on continuous wavelet transform with high accuracy.

[0005] A first aspect of the present invention provides a blade damage identification method based on continuous wavelet transform, comprising:

[0006] Construct finite element models of composite beams;

[0007] Obtaining an undamaged mode shape and a damaged mode shape of the finite element model;

[0008] Performing boundary amplification processing on the first-order derivatives of the undamaged mode vibration shape and the damaged mode vibration shape to eliminate boundary effects of the undamaged mode vibration shape and the damaged mode vibration shape;

[0009] The first-order derivative after boundary amplification is processed by continuous wavelet transform to obtain the damage identification result;

[0010] Obtain the wavelet peak position and wavelet peak size of different degrees of damage;

[0011] Damage location and damage quantification are performed according to the wavelet peak position and the wavelet peak size.

[0012] Optionally, the method further comprises:

[0013] Choose a compactly supported wavelet as the wavelet basis;

[0014] scaling the wavelet basis to obtain wavelet clusters of different scales;

[0015] Performing space-frequency signal conversion according to the wavelet cluster;

[0016] The wavelet is an oscillatory function of finite length having a value in a finite interval and having a mean of zero.

[0017] Optionally, the performing boundary augmentation processing on the undamaged mode vibration shape and the first-order derivative of the damaged mode vibration shape includes:

[0018] Configure the model's rated speed;

[0019] According to the rated speed, the first-order derivative of the first-order modal data of the intact and damaged composite blades is obtained to obtain the data to be identified;

[0020] The boundary of the data to be identified is expanded to eliminate the boundary effect.

[0021] Optionally, the method further comprises:

[0022] Select ReverseBior1.3 wavelet to solve the wavelet transform coefficients of the data to be identified.

[0023] Optionally, the performing damage location and damage quantification according to the wavelet peak position and the wavelet peak size includes:

[0024] Calculating the difference between the undamaged wavelet coefficient and the damaged wavelet coefficient, wherein the position where the difference is not zero indicates the abnormal position of the undamaged mode and the damaged mode;

[0025] Performing absolute value processing on the difference, and determining the blade damage position according to the difference after the absolute value processing;

[0026] The damage levels are simulated and analyzed quantitatively.

[0027] Another aspect of an embodiment of the present invention provides a blade damage identification system based on continuous wavelet transform, comprising:

[0028] The first module is used to construct a finite element model of a composite beam;

[0029] The second module is used to obtain the undamaged mode vibration shape and the damaged mode vibration shape of the finite element model;

[0030] The third module is used to perform boundary amplification processing on the first-order derivatives of the undamaged mode vibration mode and the damaged mode vibration mode to eliminate the boundary effects of the undamaged mode vibration mode and the damaged mode vibration mode;

[0031] The fourth module is used to perform continuous wavelet transform processing on the first-order derivative after the boundary amplification processing to obtain the damage identification result;

[0032] The fifth module is used to obtain the wavelet peak position and wavelet peak size of different degrees of damage;

[0033] The sixth module is used to locate and quantify damage according to the wavelet peak position and the wavelet peak size.

[0034] Another aspect of an embodiment of the present invention provides an electronic device, including a processor and a memory;

[0035] The memory is used to store programs;

[0036] The processor executes the program to implement the method described above.

[0037] Another aspect of an embodiment of the present invention provides a computer-readable storage medium, wherein the storage medium stores a program, and the program is executed by a processor to implement the method described above.

[0038] The embodiment of the present invention also discloses a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device can read the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the above method.

[0039] The embodiment of the present invention first constructs a finite element model of a composite beam; obtains the undamaged modal vibration mode and the damaged modal vibration mode of the finite element model; performs boundary amplification processing on the first-order derivatives of the undamaged modal vibration mode and the damaged modal vibration mode to eliminate the boundary effects of the undamaged modal vibration mode and the damaged modal vibration mode; performs continuous wavelet transform processing on the first-order derivative after boundary amplification processing to obtain damage identification results; obtains the wavelet peak position and wavelet peak size of different degrees of damage; and performs damage location and damage quantification according to the wavelet peak position and the wavelet peak size. The present invention improves the accuracy of damage identification. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 A schematic diagram of a boundary displacement peak value provided by an embodiment of the present invention;

[0042] Figure 2 An overall implementation step diagram provided for an embodiment of the present invention;

[0043] Figure 3 A flowchart of a simulation process provided by an embodiment of the present invention;

[0044] Figure 4 A schematic diagram of wavelet peak linear fitting provided by an embodiment of the present invention;

[0045] Figure 5 A schematic diagram of a simulated composite blade model provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] In view of the problems existing in the prior art, an embodiment of the present invention provides a blade damage identification method based on continuous wavelet transform, such as Figure 2 As shown, the method of the present invention comprises the following steps:

[0048] Construct finite element models of composite beams;

[0049] Obtaining an undamaged mode shape and a damaged mode shape of the finite element model;

[0050] Performing boundary amplification processing on the first-order derivatives of the undamaged mode vibration shape and the damaged mode vibration shape to eliminate boundary effects of the undamaged mode vibration shape and the damaged mode vibration shape;

[0051] The first-order derivative after boundary amplification is processed by continuous wavelet transform to obtain the damage identification result;

[0052] Obtain the wavelet peak position and wavelet peak size of different degrees of damage;

[0053] Damage location and damage quantification are performed according to the wavelet peak position and the wavelet peak size.

[0054] Optionally, the method further comprises:

[0055] Choose a compactly supported wavelet as the wavelet basis;

[0056] scaling the wavelet basis to obtain wavelet clusters of different scales;

[0057] Performing space-frequency signal conversion according to the wavelet cluster;

[0058] The wavelet is an oscillatory function of finite length having a value in a finite interval and having a mean of zero.

[0059] Optionally, the performing boundary augmentation processing on the undamaged mode vibration shape and the first-order derivative of the damaged mode vibration shape includes:

[0060] Configure the model's rated speed;

[0061] According to the rated speed, the first-order derivative of the first-order modal data of the intact and damaged composite blades is obtained to obtain the data to be identified;

[0062] The boundary of the data to be identified is expanded to eliminate the boundary effect.

[0063] Optionally, the method further comprises:

[0064] Select ReverseBior1.3 wavelet to solve the wavelet transform coefficients of the data to be identified.

[0065] Optionally, the performing damage location and damage quantification according to the wavelet peak position and the wavelet peak size includes:

[0066] Calculating the difference between the undamaged wavelet coefficient and the damaged wavelet coefficient, wherein the position where the difference is not zero indicates the abnormal position of the undamaged mode and the damaged mode;

[0067] Performing absolute value processing on the difference, and determining the blade damage position according to the difference after the absolute value processing;

[0068] The damage levels are simulated and analyzed quantitatively.

[0069] Another aspect of an embodiment of the present invention provides a blade damage identification system based on continuous wavelet transform, comprising:

[0070] The first module is used to construct a finite element model of a composite beam;

[0071] The second module is used to obtain the undamaged mode vibration shape and the damaged mode vibration shape of the finite element model;

[0072] The third module is used to perform boundary amplification processing on the first-order derivatives of the undamaged mode vibration mode and the damaged mode vibration mode to eliminate the boundary effects of the undamaged mode vibration mode and the damaged mode vibration mode;

[0073] The fourth module is used to perform continuous wavelet transform processing on the first-order derivative after the boundary amplification processing to obtain the damage identification result;

[0074] The fifth module is used to obtain the wavelet peak position and wavelet peak size of different degrees of damage;

[0075] The sixth module is used to locate and quantify damage according to the wavelet peak position and the wavelet peak size.

[0076] Another aspect of an embodiment of the present invention provides an electronic device, including a processor and a memory;

[0077] The memory is used to store programs;

[0078] The processor executes the program to implement the method described above.

[0079] Another aspect of an embodiment of the present invention provides a computer-readable storage medium, wherein the storage medium stores a program, and the program is executed by a processor to implement the method described above.

[0080] The embodiment of the present invention also discloses a computer program product or a computer program, which includes a computer instruction stored in a computer-readable storage medium. A processor of a computer device can read the computer instruction from the computer-readable storage medium, and the processor executes the computer instruction, so that the computer device executes the above method.

[0081] The specific implementation process of the present invention is described in detail below in conjunction with the accompanying drawings:

[0082] The present invention provides a method for identifying damage of a rotating composite blade based on continuous wavelet transform, including: constructing a finite element model of a composite blade; processing the data of the first-order modal vibration mode and the boundary augmentation form for eliminating the wavelet boundary effect; selecting the wavelet basis; analyzing the position and size of the wavelet peak at the same damage position and different damage degrees, and quantifying the damage degree. The present invention can realize the identification and determination of the damage degree and position of the composite layer, overcome the influence of the complex damping of the composite damping layer on the accuracy of damage identification, and improve the efficiency and accuracy of damage identification.

[0083] First, the continuous wavelet transform (CWT) is described below:

[0084] Wavelet transform first needs to select a compactly supported wavelet as the wavelet basis, so as to obtain wavelet clusters of different scales by scaling, thereby achieving the conversion of space-frequency signals. At the same time, ReverseBior1.3 reverse biorthogonal spline wavelet is selected for damage identification of wavelet transform. ReverseBior wavelet has compact support bidirectionality, which makes the wavelet transform symmetrical and can well describe the displacement space signal. This type of wavelet function can also well solve the contradiction between orthogonality and linear phase, and accurately reconstruct the spatial signal.

[0085] A wavelet is a finite length oscillating function ψ∈L with a value in a finite interval and a mean of zero. 2 (R):

[0086]

[0087] Among them, ||ψ||=1 and is centered at x=0.

[0088] The function ψ(x) is called the wavelet basis and must satisfy the wavelet admissible conditions:

[0089]

[0090] Where Ψ(ω) is the Fourier transform function of ψ(x).

[0091] Given a mother wavelet ψ(x), we can construct a wavelet family ψ u，s (x)

[0092]

[0093] The real numbers s and u represent the scale parameter and displacement parameter respectively. The wavelet function family is an extension of the mother wavelet ψ(x).

[0094] For a given signal f(x), where variable x is time or space, the continuous wavelet transform is performed by integrating the product of the signal function and the wavelet function:

[0095]

[0096] The solution to the continuous wavelet transform is to solve the function of u and s, which is used as ψ in the fixed wavelet function. u，s The component of (x) indicates the similarity between the signal in this part and the wavelet signal. When the inner product is 0, the two signals are orthogonal; when the inner product is 1, it means that the two signals are extremely similar. Therefore, CWT f The value is positively correlated with the similarity between the signal and the wavelet.

[0097] Next, the process of data processing and eliminating the boundary effect of wavelet analysis is described:

[0098] The definition of continuous wavelet transform (cwt) is: the integral of the product of the wavelet and the infinite length signal, that is, x∈(-∞,∞). Since the measured signal is within a finite length. Therefore, distortion will occur at the boundary, resulting in abnormal peaks in the wavelet coefficients at the left and right boundaries. This phenomenon is called boundary effect. In order to obtain a wavelet peak that better meets the recognition requirements, this part of the distorted signal is separated and eliminated. Since it is difficult to ensure the continuity of the signal by eliminating a single copy of the boundary value, it runs counter to the differential nature of wavelet analysis. In this paper, fitting and extending the boundary signal can effectively reduce the boundary peak, and at the same time, it can also make the signal have a certain degree of continuity.

[0099] Based on the cause of the boundary effect, this paper uses the curvature of two points on the left and right boundaries of the differential curve to extend and obtain its fitting curve. In order to completely eliminate the influence of the wavelet transform boundary effect, the length of the fitting curve is equivalent to the length of the original data. Figure 1 As shown, the position signal is expanded and extended to generate abnormal peaks at both ends, and the effective position signal and wavelet coefficients in the middle are retained by moving the boundary to obtain the recognition result with a fixed sampling frequency.

[0100] The specific process of damage identification is described below:

[0101] Wavelets are highly sensitive to subtle changes, breakdown points or discontinuities in signals. The damage mode of the blade is used as a spatial signal, and the peak value and position of the mutation caused by the damage can be obtained by spatial wavelet transform. Then, by constructing a correlation function between the peak value and the degree of damage, the degree of damage can be determined.

[0102] The basic steps of damage identification based on continuous wavelet transform of modal displacement of finite element model are:

[0103] (1) Use Abaqus software to construct a finite element model based on specific physical property parameters.

[0104] (2) The model is set to a fixed rated speed, and the first-order derivative of the first-order modal data of the intact and damaged composite blades is obtained using the finite element software to obtain the data to be identified.

[0105] (3) Expand the boundaries of the data to be identified and eliminate boundary effects.

[0106] (4) Select the ReverseBior1.3 wavelet to solve the wavelet transform coefficients for the identified data respectively w indicates an intact structure. d indicates a damaged structure.

[0107] (5) Solving for the undamaged wavelet coefficients and the damage wavelet coefficient The difference The non-zero values ​​indicate the abnormal positions of the undamaged mode and the damaged mode.

[0108] (6) To reduce the recognition error caused by rotation,

[0109] (7) According to The damage location is determined by the peak of the image.

[0110] (8) Simulate different damage levels and quantitatively analyze the damage level.

[0111] The beneficial effects of the method of the present invention are further verified by simulation calculation below:

[0112] according to Figure 3 In this section, the composite blade is simplified into a composite beam for Abaqus model construction. The simplified beam model analyzed in this section has a length of L = 0.3m and a width of b = 2.54×10 -2 m, the width of its constraint layer is h c =1.5×10 -4 m, the width of the foundation beam is h c =1.5×10 -3 m. The rotation speed is Ω. And assume that among the 12 units, the i-th unit close to the shaft is damaged. The damage coefficient is α. Unless otherwise required, the material properties in the analysis are listed in Table 1, which shows the material properties of the composite beam. This embodiment performs finite element analysis on the damage of the constraint layer and the foundation beam of the working condition set in Table 2 at a rated speed of 14.4r / min. By changing the Young's modulus of some units, the local stiffness reduction of the composite blade due to damage is simulated. The damage percentage is constructed according to the percentage of reduction in Young's modulus.

[0113] Table 1

[0114]

[0115] Table 2

[0116]

[0117]

[0118] Figure 4 The curve fitted by the scatter plot of the four working conditions in Table 2 above is compared with the natural logarithm scatter plot of the wavelet peak value identified by the stiffness degradation with a step size of 10%. It can basically predict the multiple newly introduced wavelet coefficient peaks. This basically reveals the correlation between the damage degree and the wavelet coefficient peak. In actual engineering, a damage model is established based on this to quantify the degree of damage.

[0119] In order to verify the strong practicability of this type of analysis method, this paper uses Abaqus simulation software, such as Figure 4 As shown in the figure, a simulation model of a composite wind turbine blade is established. The blade length is L = 12m. The rotation speed is 10rad / s. It is assumed that the third unit close to the shaft of the 12 units is damaged. One end of the blade is designated as a completely fixed boundary, and the mesh is constructed using C3D8R (eight-node linear hexahedron unit) units.

[0120] The first-order modal vibration shapes of the undamaged and damaged blades at the same position are extracted for damage identification. Through wavelet transform analysis, we can get Figure 5 , proving that this type of damage identification method can also be effectively used in the face of rotating composite blade models.

[0121] In summary, the present invention performs continuous wavelet transform analysis on the first-order derivative of the position based on the modal data of the rotating beam to obtain the damage position of the rotating beam. The example shows that the wavelet analysis using the first-order derivative is easier to eliminate the boundary effect of the wavelet coefficients obtained by using the modal data itself, and at the same time, the wavelet coefficients with a single peak value can be obtained to facilitate the damage degree analysis. The damage degree analysis is performed by the peak fitting curve method, and the peak values ​​of the wavelet coefficients corresponding to different degrees of damage are successfully predicted. This establishes a theoretical basis for damage degree identification in actual damage identification.

[0122] In some selectable embodiments, the function / operation mentioned in the block diagram may not occur in the order mentioned in the operation diagram. For example, depending on the function / operation involved, the two boxes shown in succession can actually be executed substantially simultaneously or the boxes can sometimes be executed in reverse order. In addition, the embodiment presented and described in the flow chart of the present invention is provided by way of example, for the purpose of providing a more comprehensive understanding of technology. The disclosed method is not limited to the operation and logic flow presented herein. Selectable embodiments are expected, wherein the order of various operations is changed and the sub-operation of a part for which is described as a larger operation is performed independently.

[0123] In addition, although the present invention is described in the context of functional modules, it should be understood that, unless otherwise specified, one or more of the functions and / or features described may be integrated into a single physical device and / or software module, or one or more functions and / or features may be implemented in separate physical devices or software modules. It is also understood that a detailed discussion of the actual implementation of each module is unnecessary for understanding the present invention. More specifically, in view of the properties, functions, and internal relationships of the various functional modules in the device disclosed herein, the actual implementation of the module will be understood within the conventional skills of the engineer. Therefore, those skilled in the art can implement the present invention set forth in the claims without excessive experimentation using ordinary techniques. It is also understood that the specific concepts disclosed are merely illustrative and are not intended to limit the scope of the present invention, which is determined by the full scope of the appended claims and their equivalents.

[0124] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0125] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0126] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0127] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0128] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0129] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0130] The above is a specific description of the preferred implementation of the present invention, but the present invention is not limited to the described embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the present invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A blade damage identification method based on continuous wavelet transform, characterized in that: include: Construct finite element models of composite beams; Obtaining an undamaged mode shape and a damaged mode shape of the finite element model; Performing boundary amplification processing on the first-order derivatives of the undamaged mode vibration shape and the damaged mode vibration shape to eliminate boundary effects of the undamaged mode vibration shape and the damaged mode vibration shape; The first-order derivative after boundary amplification is processed by continuous wavelet transform to obtain the damage identification result; Obtain the wavelet peak position and wavelet peak size of different degrees of damage; Perform damage location and damage quantification according to the wavelet peak position and the wavelet peak size; The performing boundary expansion processing on the first-order derivatives of the undamaged mode vibration shape and the damaged mode vibration shape comprises: Configure the model's rated speed; According to the rated speed, the first-order derivative of the first-order modal data of the intact and damaged composite blades is obtained to obtain the data to be identified; The boundary of the data to be identified is expanded to eliminate the boundary effect.

2. The blade damage identification method based on continuous wavelet transform according to claim 1 is characterized in that: The method further comprises: Choose a compactly supported wavelet as the wavelet basis; scaling the wavelet basis to obtain wavelet clusters of different scales; Performing space-frequency signal conversion according to the wavelet cluster; The wavelet is an oscillatory function of finite length having a value in a finite interval and having a mean of zero.

3. The blade damage identification method based on continuous wavelet transform according to claim 1 is characterized in that: The method further comprises: Select ReverseBior1.3 wavelet to solve the wavelet transform coefficients of the data to be identified.

4. The blade damage identification method based on continuous wavelet transform according to claim 1 is characterized in that: The damage location and damage quantification according to the wavelet peak position and the wavelet peak size include: Calculating the difference between the undamaged wavelet coefficient and the damaged wavelet coefficient, wherein the position where the difference is not zero indicates the abnormal position of the undamaged mode and the damaged mode; Performing absolute value processing on the difference, and determining the blade damage position according to the difference after the absolute value processing; The damage levels are simulated and analyzed quantitatively.

5. The blade damage identification system based on continuous wavelet transform is characterized by: include: The first module is used to construct a finite element model of a composite beam; The second module is used to obtain the undamaged mode vibration shape and the damaged mode vibration shape of the finite element model; The third module is used to perform boundary amplification processing on the first-order derivatives of the undamaged mode vibration mode and the damaged mode vibration mode to eliminate the boundary effects of the undamaged mode vibration mode and the damaged mode vibration mode; The fourth module is used to perform continuous wavelet transform processing on the first-order derivative after the boundary amplification processing to obtain the damage identification result; The fifth module is used to obtain the wavelet peak position and wavelet peak size of different degrees of damage; The sixth module is used to locate and quantify damage according to the wavelet peak position and the wavelet peak size; The third module is specifically used for: Configure the model's rated speed; According to the rated speed, the first-order derivative of the first-order modal data of the intact and damaged composite blades is obtained to obtain the data to be identified; The boundary of the data to be identified is expanded to eliminate the boundary effect.

6. An electronic device, characterized in that: including a processor and a memory; The memory is used to store programs; The processor executes the program to implement the method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that: The storage medium stores a program, and the program is executed by a processor to implement the method according to any one of claims 1 to 4.

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