A structural damping identification method, device and storage medium in a running state

Abstract

The application provides a structural damping identification method, device and computer storage medium in a running state, comprising: obtaining a structural vibration signal in a running state with a time length of T; determining a frequency value and a power spectral density value corresponding to a peak point of an i-th modal in the structural vibration signal; in a preset frequency band of the i-th modal, calculating an accumulated power spectral density value corresponding to the i-th modal, the accumulated power spectral density value being obtained by accumulating power spectral density values of a plurality of preset frequency points in the preset frequency band of the i-th modal, and the preset frequency band of the i-th modal being determined according to the frequency value and the power spectral density value corresponding to the peak point of the i-th modal; and using the accumulated power spectral density value to fit a pre-determined accumulated power spectral density value theoretical formula, identifying a value of a target parameter contained in the accumulated power spectral density value theoretical formula, and the target parameter comprising a damping ratio of the i-th modal. The application can improve the accuracy of the damping ratio identification method.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of engineering machinery, in particular to a structural damping identification method, device and storage medium under running state. BACKGROUND

[0002] Structural damping is one of the modal parameters of large civil structures, and it is of great significance for structural health monitoring, vibration control and state evaluation. The running state damping refers to the modal damping ratio of the structure under normal working state. Since the running state damping identification does not need to apply additional excitation source to the structure, it can directly use the vibration signal of the structure under normal working state to realize damping identification, and it is increasingly widely used in large civil engineering structures.

[0003] In recent years, for the identification of damping ratio under running state, the frequency domain method is widely used in damping ratio identification due to its strong intuitiveness and convenience. The core idea is to calculate the damping ratio according to the frequency domain information of the signal, such as half power beamwidth (HPB), power spectral density fitting (PSD) and the like. The biggest challenge of these methods applied to damping ratio identification is the interference of noise to the frequency domain information of the signal, which leads to a large deviation in the calculation of the frequency spectrum of the signal, and further affects the accuracy of the damping ratio identification. It is imperative to develop a damping ratio identification method with higher accuracy. SUMMARY

[0004] The technical problem to be solved by the present application is to overcome the shortcomings of the prior art and provide a structural damping identification method under running state, an electronic device and a computer readable storage medium.

[0005] To solve the above technical problems, the technical solution provided by the present application is:

[0006] The present application provides a structural damping identification method under running state, comprising the following steps:

[0007] S1: obtaining a structural vibration signal under running state with a time length of T;

[0008] S2: determining the frequency value and the power spectral density value corresponding to the peak point of the i-th modal in the structural vibration signal, i is the index of the structural vibration modal, and is a positive integer greater than zero;

[0009] S3: calculating the cumulative power spectral density value corresponding to the i-th modal in the preset frequency band of the i-th modal, the cumulative power spectral density value is obtained by accumulating the power spectral density values of a plurality of preset frequency points in the preset frequency band of the i-th modal, and the preset frequency band of the i-th modal is determined according to the frequency value and the power spectral density value corresponding to the peak point of the i-th modal.

[0010] S4: fitting a predetermined cumulative power spectral density value theoretical formula using the cumulative power spectral density values, identifying values of target parameters contained in the cumulative power spectral density value theoretical formula, the target parameters including a damping ratio of the i-th order modal.

[0011] Optionally, in step S2, the power spectral density value of the signal is calculated using the following formula to determine the power spectral density value corresponding to the peak point of the i-th order modal :

[0012]

[0013] wherein, represents a Fourier transform of the structural vibration signal, represents that the structural vibration signal is divided into M segments, represents an index of the number of segments, subscript is an index of the peak point of the i-th order modal, wherein, is a frequency value corresponding to the peak point of the i-th order modal, , represents a frequency resolution, represents a vector transpose, represents a complex vector conjugate transpose, represents a power spectral density value corresponding to the signal at the frequency point .

[0014] Optionally, in step S3, the preset frequency band of the i-th order modal is , wherein, is a frequency value corresponding to the peak point of the i-th order modal.

[0015] Optionally, in step S3, the cumulative power spectral density value corresponding to the i-th order modal is calculated according to the following formula:

[0016]

[0017] wherein, , represents a frequency band index within the frequency band, , is a frequency resolution, is a corresponding power spectral density value, is a cumulative power spectral density value of the frequency band .

[0018] Optionally, in step S4, the cumulative power spectral density value theoretical formula includes:

[0019]

[0020]

[0021]

[0022] wherein, , and respectively represent the cumulative power spectral density theoretical value of displacement response, velocity response and acceleration response, represent the power spectral density of modal force, is the frequency value corresponding to the peak point of the i-th modal, is the damping ratio of the i-th modal, , represents the frequency band index in the frequency band, , is the frequency resolution.

[0023] Optionally, in step S4, the cumulative power spectral density value is used to fit a predetermined cumulative power spectral density value theoretical formula, and the value of a target parameter contained in the cumulative power spectral density value theoretical formula is identified, comprising:

[0024] The cumulative power spectral density value is used to perform least square fitting on a predetermined cumulative power spectral density value theoretical formula, and the value of a target parameter contained in the cumulative power spectral density value theoretical formula is identified.

[0025] wherein, the formula of least square fitting is as follows:

[0026]

[0027] wherein, is the cumulative power spectral density value, is the cumulative power spectral density theoretical value calculated by the cumulative power spectral density value theoretical formula, wherein , represents the frequency band index in the frequency band, , is the frequency resolution, , , is the identified value of the target parameter, and respectively is the identified value of the modal force power spectral density value, the damping ratio and the frequency of the i-th modal.

[0028] The embodiment of the present application also provides an electronic device, comprising:

[0029] The acquisition module is configured to acquire a structure vibration signal in a running state with a time length of T.

[0030] determining module, configured to determine a frequency value and a power spectral density value corresponding to a peak point of an i-th order modal in the structural vibration signal, i is an index of a structural vibration modal, and is a positive integer greater than zero;

[0031] calculating module, configured to calculate an accumulated power spectral density value corresponding to the i-th order modal in a preset frequency band of the i-th order modal, the accumulated power spectral density value being obtained by accumulating power spectral density values of a plurality of preset frequency points in the preset frequency band of the i-th order modal, and the preset frequency band of the i-th order modal being determined according to the frequency value and the power spectral density value corresponding to the peak point of the i-th order modal;

[0032] recognizing module, configured to fit a predetermined accumulated power spectral density value theoretical formula by using the accumulated power spectral density value, and recognize a value of a target parameter contained in the accumulated power spectral density value theoretical formula, the target parameter including a damping ratio of the i-th order modal.

[0033] Embodiments of the present application also provide an electronic device, comprising:

[0034] a processor;

[0035] a memory for storing instructions executable by the processor;

[0036] The processor is configured to execute the instructions to implement the structural damping identification method in a running state according to the embodiments of the present application.

[0037] Embodiments of the present application also provide a computer readable storage medium, when instructions in the computer readable storage medium are executed by a processor, a structural damping identification method in a running state according to embodiments of the present application is implemented.

[0038] Compared with the prior art, the present application has the advantages that: the present application provides a structural damping identification method in a running state, a device and a storage medium, by accumulating power spectral density values of a plurality of frequency points in a preset frequency band, the accuracy of frequency domain data is improved, the influence of noise on damping ratio identification is eliminated to the greatest extent, and the accuracy of the identification method is improved. In addition, compared with the cumulative power spectral density method in the prior art, this method does not need to perform modal decomposition, can directly use the data of the selected frequency band for calculation, greatly improves the calculation efficiency, and is suitable for acceleration, displacement and speed three response types, and has wider engineering adaptability. BRIEF DESCRIPTION OF DRAWINGS

[0039] The present application will be described in more detail below based on embodiments and with reference to the accompanying drawings. In which:

[0040] Figure 1is a flow chart of a structural damping identification method in a running state provided by an embodiment of the present application;

[0041] Figure 2 is a cumulative power spectral density and accumulated power spectral density method calculation time length comparison provided by an embodiment of the present application;

[0042] Figure 3 is a damping identification result based on the accumulated power spectral density method provided by an embodiment of the present application;

[0043] Figure 4 is a damping identification result based on the accumulated power spectral density method provided by an embodiment of the present application;

[0044] Figure 5 is a structural schematic diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION

[0045] The present application will be further described below in conjunction with the drawings and specific embodiments, but the protection scope of the present application is not limited by this.

[0046] Although the present application has been described with reference to the preferred embodiments, various modifications can be made to it without departing from the scope of the present application, and equivalent components can be substituted therefor. In particular, the technical features mentioned in each embodiment can be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0047] It should be understood that although each step in the flow chart of the embodiment of the present application is displayed in sequence according to the arrow, these steps are not necessarily executed in sequence according to the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and they can be executed in other orders. Moreover, at least part of the steps in the figure can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence is not necessarily sequential, but can be alternately executed with other steps or sub-steps or stages of other steps.

[0048] It should be noted that in this paper, step codes such as S1, S2, etc. are used, the purpose of which is to more clearly and briefly express the corresponding content, and does not constitute a substantial limitation on the order, and those skilled in the art may, when implementing, perform S2 first and then perform S1, etc., but these should be within the protection scope of the embodiments of the present application.

[0049] It should be understood that the specific embodiments described herein are merely illustrative of the present application and do not limit the present application.

[0050] In the following description, the suffixes such as "module", "part", or "unit" used for an element are merely intended for facilitating explanation of the present application and do not have specific meanings or roles. Therefore, "module", "part", or "unit" can be mixedly used.

[0051] As shown in Figure 1 , a flowchart of a structural damping identification method in a running state is provided, and the structural damping identification method in a running state can be executed by a structural damping identification device in a running state. The device can be implemented in software and / or hardware, such as a server, a computer, a processor, and other electronic devices. In this embodiment, the processor of the electronic device is taken as an example, and the structural damping identification method in a running state includes:

[0052] S1: obtaining a structural vibration signal in a running state with a time length of T.

[0053] The structural vibration signal is a measured signal. In specific implementation, it can be collected by a sensor installed on the structure. For the convenience of understanding and description, the measured structural vibration signal in a running state with a time length of T is denoted as , which can be an acceleration signal, a speed signal, or a displacement signal.

[0054] S2: determining a frequency value and a power spectral density value corresponding to a peak point of an i-th mode in the structural vibration signal, i is an index of a structural vibration mode, and is a positive integer greater than zero.

[0055] In an optional embodiment, the power spectral density value of each frequency point can be determined by using a periodogram method. Specifically, the power spectral density value corresponding to the peak point of the i-th mode in the signal can be obtained by using formula (1) , and formula (1) is as follows:

[0056] (1)

[0057] wherein, represents a Fourier transform of the structural vibration signal, represents that the structural vibration signal is divided into M segments, represents an index of the number of segments, and the subscript is an index of the peak point of the i-th mode, wherein, is a frequency value corresponding to the peak point of the i-th mode, , represents a frequency resolution, This represents the transpose of a vector. This represents the conjugate transpose of a complex vector. Represents the signal at a frequency point The corresponding power spectral density value at that location.

[0058] Plot the structural vibration signal according to the above formula (1). The spectrum diagram can determine The horizontal coordinate corresponding to the peak point of each mode is the frequency value corresponding to the peak point. Substituting the frequency value corresponding to the peak point into formula (1) yields the power spectral density value corresponding to the peak point.

[0059] S3: Within the preset frequency band of the i-th mode, calculate the accumulated power spectral density value corresponding to the i-th mode. The accumulated power spectral density value is obtained by accumulating the power spectral density values ​​at several preset frequency points within the preset frequency band of the i-th mode. The preset frequency band of the i-th mode is determined based on the frequency value and power spectral density value corresponding to the peak point of the i-th mode.

[0060] In this step, the power spectral density values ​​at multiple frequency points in the preset frequency band are accumulated to eliminate the influence of noise on damping ratio identification and improve the accuracy of the identification method.

[0061] In practical implementation, the selection of the preset frequency band is crucial. The preset frequency band of the i-th mode is based on the frequency value corresponding to the peak point of the i-th mode. and power spectral density value Sure.

[0062] In an optional implementation, the preset frequency band of the i-th mode can be selected through trial calculations and verification. The corresponding power spectral density range is .

[0063] Correspondingly, the accumulated power spectral density value corresponding to the i-th mode can be calculated using formula (2):

[0064] (2)

[0065] in, , representing in Frequency band index within the frequency band , For frequency resolution, for The corresponding power spectral density value, For frequency band The cumulative power spectral density value.

[0066] The accumulated power spectral density value is within the preset frequency band At each frequency point, the power spectral density value is accumulated, and according to formula (2), the sum from to is obtained, and it is defined as .

[0067] S4: fitting the pre-determined accumulated power spectral density value theoretical formula with the accumulated power spectral density value, identifying the value of the target parameter contained in the accumulated power spectral density value theoretical formula, the target parameter including the damping ratio of the i-th modal.

[0068] In this step, the accumulated power spectral density value theoretical formula can be pre-determined, and the parameter to be identified, the damping ratio of the i-th modal, is contained in the theoretical formula. It should be noted that the accumulated power spectral density value is the measured accumulated power spectral density value, and the accumulated power spectral density value theoretical formula is fitted with the measured accumulated power spectral density value, so that the target parameter in the accumulated power spectral density value theoretical formula can be identified according to the fitting result, that is, the damping ratio of the i-th modal of the structure can be identified.

[0069] In an optional embodiment, the accumulated power spectral density value theoretical formula corresponding to different response signals can be pre-determined to include:

[0070] (3)

[0071] (4)

[0072] (5)

[0073] wherein, the calculated by formula (3) represents the accumulated power spectral density theoretical value of displacement response, that is, the accumulated power spectral density theoretical value of the structure vibration signal when the displacement signal is; the calculated by formula (4) represents the accumulated power spectral density theoretical value of velocity response, that is, the accumulated power spectral density theoretical value of the structure vibration signal when the velocity signal is; the calculated by formula (5) represents the accumulated power spectral density theoretical value of acceleration response, that is, the accumulated power spectral density theoretical value of the structure vibration signal when the acceleration signal is.

[0074] represents the power spectral density value of modal force, is the frequency value corresponding to the peak point of the i-th modal, is the damping ratio of the i-th modal, represents the frequency band index in the frequency band, , is the frequency resolution.

[0075] In an optional embodiment, least square fitting can be used to identify the values of the target parameters.

[0076] In this embodiment, it is assumed that the measured cumulative power spectral density value of the structural vibration signal is and the theoretical value of the cumulative power spectral density of the structural vibration signal is The modal force power spectral density value, the damping ratio and the frequency of the i-th mode can be obtained by minimizing the sum of squares of the difference between and as the objective function, using the “fmincon” function of MATLAB software.

[0077] (6)

[0078] wherein is the cumulative power spectral density value, is the theoretical value of the cumulative power spectral density calculated by the theoretical formula of the cumulative power spectral density, wherein represents the frequency band index within the frequency band, , is the frequency resolution, , , is the identified value of the target parameter, and the identified values of the modal force power spectral density value, the damping ratio and the frequency of the i-th mode are respectively.

[0079] In a complete embodiment, the structural damping identification method under running state specifically comprises the following steps:

[0080] Step one: estimate the power spectral density value

[0081] Step 1: first obtain the structural vibration signal under running state with a time length of T , which can be an acceleration, speed or displacement signal.

[0082] Step 2: and obtain the power spectral density value corresponding to each frequency point of the signal by formula (1).

[0083] (1)

[0084] wherein represents the Fourier transform of the structural vibration signal, represents dividing the structural vibration signal into M segments, Index representing the number of segments, subscript is the index of the peak point of the i th modal, where, is the frequency value corresponding to the peak point of the i th modal, , denotes the frequency resolution, denotes vector transposition, denotes complex vector conjugate transposition, represents the power spectral density value corresponding to the signal at the frequency point .

[0085] Step 2: Calculate the cumulative power spectral density value

[0086] Step 3: Use the peak picking method to obtain the peak point of each modal of the structural vibration signal . Assume that the horizontal coordinate of the peak point of the i th modal is i , and the corresponding vertical coordinate is . .

[0087] Step 4: Take as the frequency band of the i th modal, and the corresponding power spectral density value range is .

[0088] Step 5: Use formula (2) to calculate the cumulative power spectral density value in each frequency band.

[0089] (2)

[0090] where, , represents the frequency band index in the frequency band, , is the frequency resolution, is the corresponding power spectral density value, is the cumulative power spectral density value of the frequency band .

[0091] Step 3: Calculate the modal damping ratio

[0092] Step 6: The theoretical formula of the cumulative power spectral density value of different response signals is as shown in formulas (3) to (5).

[0093] (3)

[0094] (4)

[0095] (5)

[0096] wherein, , and respectively represent the cumulative power spectral density theoretical value of displacement response, velocity response and acceleration response, represent the power spectral density of modal force, is the frequency value corresponding to the peak point of the i-th modal, is the damping ratio of the i-th modal, , represents the frequency band index in band, , is the frequency resolution.

[0097] Step 7: assuming that the cumulative power spectral density value of the measured signal is , the cumulative power spectral density theoretical value of the signal is , the modal force, the damping ratio and the frequency of the i-th modal can be solved by minimizing the sum of squares of the difference between and as the target, using the "fmincon" function of MATLAB software.

[0098] (6)

[0099] In the formula, is the measured cumulative power spectral density value, is the cumulative power spectral density theoretical value calculated by the theoretical formula of the cumulative power spectral density value, wherein, , represents the frequency band index in band, , is the frequency resolution, , , is the identification value of the target parameter, and the identification values of the modal force power spectral density value, the damping ratio and the frequency of the i-th modal are respectively.

[0100] In the embodiment of the application, the power spectral density value of a single frequency point in a preset frequency band is accumulated to eliminate the influence of noise on the identification of the damping ratio and improve the accuracy of the identification method. In addition, compared with the cumulative power spectral density method in the prior art, the method does not need to be modal decomposed, greatly improves the calculation efficiency, and is suitable for three response types of acceleration, displacement and velocity, and has wider engineering adaptability.

[0101] In order to verify the accuracy and robustness of the method provided in the embodiment of the application, two numerical example models are established, and the main parameters are set as follows:

[0102] (1) System simulation: single degree of freedom system, three degrees of freedom system;

[0103] (2) Sampling frequency: 100Hz;

[0104] (3) Natural frequency: the fundamental frequency of the single degree of freedom system is =0.5Hz, the third order frequency of the three degrees of freedom system is =1Hz, =2Hz, =4Hz;

[0105] (4) Damping ratio: the free vibration of the simulated single degree of freedom system under four working conditions of damping ratio =0.02, =0.01, =0.005, =0.003, the third order modal damping ratio of the simulated three degrees of freedom system is =0.02, =0.01, =0.005;

[0106] (5) Initial amplitude: the initial amplitude of the single degree of freedom system is =1m, the amplitude of the third order modal of the multi-degree of freedom system is =1m, =0.2m, =0.1m;

[0107] (6) Noise level: add four kinds of Gaussian distribution random noise with mean value of zero and standard deviation of 5%, 10%, 15% and 20% of the RMS value of the free vibration signal respectively.

[0108] 1. Single degree of freedom system

[0109] Firstly, a single degree of freedom system is constructed to verify the accuracy of the method, and random vibration signals of the single degree of freedom under different damping ratios are generated by using the program. The frequency of the system is 0.888Hz, the damping ratio is taken as 0.005-0.02, the sampling time is 30000s, and the sampling frequency is 100Hz. Four kinds of methods provided by the embodiment of the application, cumulative power spectral density method (CS-PSD), cumulative power spectral density method (CPSD) in the prior art, power spectral density fitting method (Power Spectral Density, PSD) and half power beamwidth method (Half Power Beamwidth, HPB) are used for comparative research.

[0110]

[0111] From the above table 1, the cumulative power spectral density method (CS-PSD) proposed in the embodiment of the application has good recognition accuracy under different damping ratios, and the recognition error is always less than 5%, and the recognition sensitivity to different damping levels is low, which shows that it has good accuracy.

[0112] On this basis, the recognition efficiency of the cumulative power spectral density method (CS-PSD) and the cumulative power spectral density method (CPSD) under different sampling lengths is also compared, as shown in Figure 2 It can be seen that, as the data length increases, the calculation time required by the damping identification method based on the cumulative power spectral density (CPSD) increases exponentially, while the calculation time of the damping identification method based on the single-mode cumulative power spectral density (CS-PSD) also increases with the increase of the data length, but always remains within 3s.

[0113] 2.2 Three degrees of freedom system

[0114] In order to verify the recognition accuracy and robustness of the cumulative power spectral density method (CS-PSD) proposed, a three-degree-of-freedom structure dynamic model is established by using Matlab programming for subsequent damping identification, and the model parameters are shown in table 2:

[0115]

[0116] The sampling frequency is set to 100Hz, and the sampling length is set to 30000s. In order to avoid the randomness of the identification results, the application generates 100 groups of random signals for comparison and identification, and each group of signals uses the same damping identification process, and the identification results of the two methods are compared as shown in table 3.

[0117]

[0118] From the analysis results of Figure 3 and Figure 4 It can be seen that the cumulative power spectral density method has higher accuracy, and the recognition result is very stable and has low uncertainty.

[0119] The embodiment of the application also provides an electronic device, comprising:

[0120] The acquisition module is configured to acquire a structure vibration signal in a running state with a time length of T;

[0121] The determination module is configured to determine a frequency value and a power spectral density value corresponding to a peak point of an i-th mode in the structure vibration signal, i is an index of a structure vibration mode, and is a positive integer greater than zero;

[0122] The calculation module is used to calculate the accumulated power spectral density value corresponding to the i-th mode in the preset frequency band of the i-th mode. The accumulated power spectral density value is obtained by accumulating the power spectral density values ​​of several preset frequency points in the preset frequency band of the i-th mode. The preset frequency band of the i-th mode is determined according to the frequency value and power spectral density value corresponding to the peak point of the i-th mode.

[0123] The identification module is used to fit the accumulated power spectral density value to a predetermined theoretical formula for the accumulated power spectral density value, and to identify the value of the target parameter contained in the theoretical formula for the accumulated power spectral density value, wherein the target parameter includes the damping ratio of the i-th mode.

[0124] Optionally, in the determining module, the power spectral density value corresponding to the peak point of the i-th mode is calculated according to the following formula;

[0125]

[0126] in, The Fourier transform of the vibration signal of the structure is represented. This represents dividing the structural vibration signal into M segments. Index representing the number of segments, subscript It is the index of the peak point of the i-th mode, where, Let be the frequency value corresponding to the peak point of the i-th mode. , Indicates frequency resolution. This represents the transpose of a vector. This represents the conjugate transpose of a complex vector. Represents the signal at a frequency point The corresponding power spectral density value at that location.

[0127] Optionally, in the calculation module, the preset frequency band domain of the i-th mode is: , Let be the frequency value corresponding to the peak point of the i-th mode.

[0128] Optionally, in the calculation module, the accumulated power spectral density value corresponding to the i-th mode is calculated according to the following formula:

[0129]

[0130] in, , representing in Frequency band index within the frequency band , For frequency resolution, for The corresponding power spectral density value, is the cumulative power spectral density value of the frequency band .

[0131] Optionally, in the identification module, the cumulative power spectral density value theoretical formula comprises:

[0132]

[0133]

[0134]

[0135] wherein, , and respectively represent the cumulative power spectral density theoretical value of displacement response, velocity response and acceleration response, represents the power spectral density of modal force, is the frequency value corresponding to the peak point of the i-th order modal, is the damping ratio of the i-th order modal, , represents the frequency band index within the frequency band, , is the frequency resolution.

[0136] Optionally, in the identification module, the cumulative power spectral density value is used to fit a predetermined cumulative power spectral density value theoretical formula, and the value of a target parameter contained in the cumulative power spectral density value theoretical formula is identified, comprising:

[0137] The cumulative power spectral density value is used to perform least square fitting on a predetermined cumulative power spectral density value theoretical formula, and the value of a target parameter contained in the cumulative power spectral density value theoretical formula is identified.

[0138] wherein, the formula of the least square fitting is as follows:

[0139]

[0140] wherein, is the cumulative power spectral density value, is the cumulative power spectral density theoretical value calculated by the cumulative power spectral density value theoretical formula, wherein, , represents the frequency band index within the frequency band, , is the frequency resolution, , , The identified values ​​of the target parameters are the modal force power spectral density, damping ratio, and frequency of the i-th mode, respectively.

[0141] The electronic device provided in this invention eliminates the influence of noise on damping ratio identification by accumulating the power spectral density values ​​at a single frequency point in a preset frequency band, thereby improving the accuracy of the identification method. Furthermore, compared to the cumulative power spectral density method in the prior art, this method does not require mode decomposition, greatly improving computational efficiency, and is applicable to three response types: acceleration, displacement, and velocity, thus having wider engineering applicability.

[0142] Based on the same inventive concept as the foregoing embodiments, this invention also provides an electronic device, such as... Figure 5 As shown, the electronic device includes: a processor 510 and a memory 511 storing a computer program; wherein, Figure 5 The processor 510 shown in the diagram does not indicate that there is only one processor 510, but only indicates the positional relationship of the processor 510 relative to other devices. In practical applications, there can be one or more processors 510; similarly, Figure 5 The memory 511 illustrated in the diagram has the same meaning, that is, it is only used to indicate the positional relationship of memory 511 relative to other devices. In practical applications, the number of memories 511 can be one or more. When the processor 510 runs the computer program, the structural damping identification method described above in the operating state is implemented. The electronic device may also include: at least one network interface 512. The various components in the electronic device are coupled together through a bus system 513. It is understood that the bus system 513 is used to realize the connection and communication between these components. In addition to the data bus, the bus system 513 also includes a power bus, a control bus, and a status signal bus. However, for the sake of clarity, in Figure 5 The general designated all buses as Bus System 513.

[0143] The memory 511 can be a volatile memory or a nonvolatile memory, and can also include both a volatile and a nonvolatile memory. The nonvolatile memory can be a Read Only Memory (ROM), a Programmable Read-Only Memory (PROM), an Erasable Programmable Read-Only Memory (EPROM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a Ferroelectric Random Access Memory (FRAM), a Flash Memory, a magnetic storage memory, an optical storage memory, or a Compact Disc Read-Only Memory (CD-ROM). The magnetic storage memory can be a magnetic disk memory or a magnetic tape memory. The volatile memory can be a Random Access Memory (RAM) used as an external cache. By way of example and not limitation, many forms of RAM can be used, such as a Static Random Access Memory (SRAM), a Synchronous Static Random Access Memory (SSRAM), a Dynamic Random Access Memory (DRAM), a Synchronous Dynamic Random Access Memory (SDRAM), a Double Data Rate Synchronous Dynamic Random Access Memory (DDR SDRAM), an Enhanced Synchronous Dynamic Random Access Memory (ESDRAM), a Sync Link Dynamic Random Access Memory (SLDRAM), or a Direct Rambus Random Access Memory (DRRAM).The memory 511 described in the embodiments of the present application is intended to include, but is not limited to, these and any other suitable type of memory.

[0144] The memory 511 in the embodiments of the present application is configured to store various types of data to support the operation of the electronic device. Examples of the data include: any computer programs for operating on the electronic device, such as an operating system and application programs; contact data; phonebook data; messages; pictures; videos; and the like. The operating system contains various system programs, for example, a framework layer, a core library layer, a driver layer, and the like, for implementing various basic services and processing hardware-based tasks. The application programs can contain various application programs, for example, a media player (Media Player), a browser (Browser), and the like, for implementing various application services. Here, the program for implementing the method of the embodiments of the present application can be contained in the application programs.

[0145] Based on the same inventive concept as the foregoing embodiments, the present embodiment also provides a computer readable storage medium, which stores a computer program, and can be a ferromagnetic random access memory (FRAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a flash memory, a magnetic surface memory, an optical disc, a compact disc read-only memory (CD-ROM), or the like. The computer readable storage medium can also be various devices including one or any combination of the above memories, such as a server. When the instructions stored therein are executed by a processor, the structural damping identification method in the running state described in the foregoing embodiments is implemented.

[0146] The technical features of the above embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above embodiments are described, however, as long as the combinations of the technical features do not exist contradictions, they should be considered as the scope of the present disclosure.

[0147] In this document, the terms "comprise", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0148] The above merely provides the specific implementation of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of the change or replacement within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A method for identifying structural damping in an operating state, characterized by, The method comprises the following steps: S1: obtaining a structural vibration signal in a running state with a time length of T; S2: determining a frequency value and a power spectral density value corresponding to a peak point of an i-th modal in the structural vibration signal, i being an index of a structural vibration modal and being a positive integer greater than zero; S3: calculating an accumulated power spectral density value corresponding to the i-th modal in a preset frequency band of the i-th modal, the accumulated power spectral density value being obtained by accumulating power spectral density values of a plurality of preset frequency points in the preset frequency band of the i-th modal, the preset frequency band of the i-th modal being determined according to the frequency value and the power spectral density value corresponding to the peak point of the i-th modal; S4: fitting a predetermined accumulated power spectral density value theoretical formula by using the accumulated power spectral density value, and identifying a value of a target parameter contained in the accumulated power spectral density value theoretical formula, the target parameter including a damping ratio of the i-th modal; The accumulated power spectral density value theoretical formula includes: wherein, , and represent the theoretical values of the cumulative power spectral density of displacement response, velocity response and acceleration response, respectively, represents the power spectral density of modal force, is the frequency value corresponding to the peak point of the i-th modal, is the damping ratio of the i-th modal, , represents the frequency band index within the frequency band, , is the frequency resolution.

2. The method of claim 1, wherein, In step S2, the power spectral density value of the signal is calculated by using the following formula to determine the power spectral density value corresponding to the peak point of the i-th order mode : wherein, denotes the Fourier transform of the structural vibration signal, denotes the division of the structural vibration signal into M segments, denotes an index of the number of segments, subscript is an index of the peak point of the i-th order mode, wherein, is a frequency value corresponding to the peak point of the i-th order mode, , denotes the frequency resolution, denotes the vector transpose, denotes the complex vector conjugate transpose, denotes the power spectral density value corresponding to the signal at the frequency point .

3. The method according to claim 1 or 2, characterized in that, In step S3, the preset frequency band of the i-th order mode is , is the frequency value corresponding to the peak point of the i-th order mode.

4. The method of claim 3, wherein, In step S3, the accumulated power spectral density value corresponding to the i-th modal is calculated according to the following formula: wherein, , represents a frequency band index within the frequency band, , is a frequency resolution, is a corresponding power spectral density value, is an accumulated power spectral density value of the frequency band .

5. The method of claim 1, wherein, In step S4, the fitting of the predetermined accumulated power spectral density value theoretical formula by using the accumulated power spectral density value and the identification of the value of the target parameter contained in the accumulated power spectral density value theoretical formula include: The accumulated power spectral density value theoretical formula is fitted by using the least square method, and the value of the target parameter contained in the accumulated power spectral density value theoretical formula is identified; The formula of the least square method fitting is as follows: wherein is the accumulated power spectral density value, is a theoretical accumulated power spectral density value calculated from a theoretical formula of the accumulated power spectral density value, wherein represents the identification value of the target parameter, respectively the modal force power spectral density value, the damping ratio and the frequency of the i-th modal. is a frequency band index within the frequency band, , is a frequency resolution, , , is the identification value of the target parameter, respectively the modal force power spectral density value, the damping ratio and the frequency of the i-th modal.

6. An electronic device, comprising: It comprises: An acquisition module is configured to acquire a structural vibration signal in a running state with a time length of T; A determination module is configured to determine a frequency value and a power spectral density value corresponding to a peak point of an i-th modal in the structural vibration signal, i being an index of a structural vibration modal and being a positive integer greater than zero; A calculation module is configured to calculate an accumulated power spectral density value corresponding to the i-th modal in a preset frequency band of the i-th modal, the accumulated power spectral density value being obtained by accumulating power spectral density values of a plurality of preset frequency points in the preset frequency band of the i-th modal, the preset frequency band of the i-th modal being determined according to the frequency value and the power spectral density value corresponding to the peak point of the i-th modal; An identification module is configured to fit a predetermined accumulated power spectral density value theoretical formula by using the accumulated power spectral density value, and identify a value of a target parameter contained in the accumulated power spectral density value theoretical formula, the target parameter including a damping ratio of the i-th modal; The accumulated power spectral density value theoretical formula includes: wherein, , and respectively represent the theoretical values of the cumulative power spectral density of displacement response, velocity response and acceleration response, represent the power spectral density of modal force, is the frequency value corresponding to the peak point of the i-th modal, is the damping ratio of the i-th modal, , represents the frequency band index within the frequency band, , is the frequency resolution.

7. An electronic device, comprising: It comprises a processor and a memory, and the memory stores a computer program, which, when executed by the processor, implements the method of any one of claims 1-5.

8. A computer-readable storage medium, characterized in that, A computer instruction is stored, and the instruction, when executed, implements the method of any one of claims 1-5.

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