Power grid facility vulnerability evaluation method and system based on vulnerability evaluation model

Abstract

The invention discloses a power grid facility vulnerability evaluation method and system based on a vulnerability evaluation model, and relates to the technical field of electric power engineering. Constructing a vulnerability evaluation model; establishing a transmission tower vulnerability curve; the vulnerability of the transmission tower is corrected, and a vulnerability value of the transmission tower is determined; and evaluating the vulnerability of the transmission tower according to the vulnerability value of the transmission tower. According to the method, through deep analysis of the tower deformation failure mode, the accuracy of vulnerability evaluation is improved, and the defect of insufficient understanding of a tower failure mechanism in the prior art is overcome, so that the scientificity and reliability of evaluation are improved. Meanwhile, a dynamic vulnerability curve is constructed based on Weibull distribution, and a correction mechanism is introduced, so that the evaluation model can be adjusted in real time according to environmental changes, the dynamic adaptability of the model is enhanced, and the limitation of a traditional static model is effectively overcome.

Description

Technical Field

[0001] The present invention relates to the technical field of electric power engineering, and in particular to a method and system for evaluating the vulnerability of power grid facilities based on a vulnerability evaluation model. Background Art

[0002] In the development of the power system, the safety and reliability of power grid facilities have always been an important research direction. Especially in the context of complex geological conditions and frequent extreme climate events, the structural stability and disaster resistance of transmission towers have attracted much attention. In recent years, with the expansion of the scale of power grids and the extension of transmission lines, the diversity of the environment in which the towers are located has made them face more uncertain factors, such as the impact of natural disasters such as earthquakes, rainstorms, and strong winds. In addition, since the transmission towers are exposed to the natural environment for a long time, the stress conditions are complex, and the aging of their structural materials and uneven settlement of the foundation will also increase the vulnerability of the towers. Therefore, the accurate assessment of the vulnerability of power grid facilities, especially the analysis of the deformation and failure modes of towers under various environmental loads, has become an important part of power grid operation and maintenance. Traditional assessment methods mostly rely on empirical models or simple structural safety factors, but in actual operation, due to the lack of in-depth analysis of the damage to the tower structure, it is difficult to accurately reflect the actual vulnerability of the tower, and it is difficult to make an accurate assessment of the risks under different environmental conditions.

[0003] Although the existing vulnerability assessment technology takes into account the structural parameters and environmental loads of transmission towers to a certain extent, its assessment model is mostly static or a single mathematical model, which cannot flexibly respond to a variety of dynamic conditions. Traditional methods mainly conduct preliminary assessments of the vulnerability of towers based on historical data and static parameters, and fail to deeply explore the impact of different failure modes on vulnerability, resulting in possible deviations between the assessment results and the actual situation in practical applications. In addition, existing methods often lack systematic analysis of multivariate parameters (such as tower inclination, material aging, and foundation settlement), which limits their adaptability to complex geographical and environmental conditions. Our invention comprehensively analyzes the deformation and failure modes of towers, combines the Weibull distribution function to establish a dynamic vulnerability curve, and further uses a modified model to refine the calculation of vulnerability values, making the vulnerability assessment results more accurate. This method greatly improves the ability to judge the potential vulnerability of towers on the basis of traditional technologies, and provides a more scientific basis for disaster prevention and risk management of power grid facilities. Summary of the invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by the present invention is that the existing vulnerability assessment methods lack in-depth analysis of the deformation and failure modes of transmission towers under various environmental loads, and it is difficult to accurately identify the failure characteristics of towers under different disaster conditions. Traditional evaluation models are mostly static models, which cannot be accurately adjusted according to the actual state of the towers and dynamic environmental factors, resulting in deviations between the evaluation results and the actual situation. The existing methods lack refined analysis of multivariate factors (such as inclination, material properties, etc.) when determining the vulnerability value of the tower, resulting in limited accuracy of the vulnerability assessment.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for evaluating the vulnerability of power grid facilities based on a vulnerability evaluation model, which comprises the following steps:

[0007] Analyze the deformation and failure mode of the tower; construct a vulnerability assessment model; establish a transmission tower vulnerability curve; correct the transmission tower vulnerability and determine the transmission tower vulnerability value; and conduct a transmission tower vulnerability assessment based on the transmission tower vulnerability value.

[0008] As a preferred solution of the vulnerability assessment method for power grid facilities based on the vulnerability assessment model described in the present invention, the analysis of the deformation and failure mode of the tower includes deriving the tower failure mode based on relative deformation parameters.

[0009] As a preferred solution of the vulnerability assessment method of power grid facilities based on the vulnerability assessment model described in the present invention, wherein: the vulnerability assessment model is expressed as:

[0010] V = f(I, R)

[0011] Among them, I represents the ground collapse intensity caused by mining subsidence, and R represents the vulnerability of the transmission tower.

[0012] As a preferred solution of the vulnerability assessment method of power grid facilities based on the vulnerability assessment model of the present invention, wherein: the transmission tower vulnerability curve is established by the cumulative probability distribution function of Weibull distribution, and the probability density in the cumulative probability distribution function of Weibull distribution is expressed as,

[0013]

[0014] Among them, x represents the scale parameter, λ is the size parameter, and k represents the shape parameter.

[0015] As a preferred solution of the vulnerability assessment method of power grid facilities based on the vulnerability assessment model of the present invention, the modification of the vulnerability of the transmission tower includes selecting a cumulative distribution function to fit and calculate the modified Weibull distribution of the vulnerability of the transmission line tower. The definition is as follows:

[0016]

[0017] Among them, E represents the vulnerability of the transmission line tower, and a represents the inclination of the transmission tower.

[0018] As a preferred embodiment of the vulnerability assessment method for power grid facilities based on the vulnerability assessment model described in the present invention, the determination of the vulnerability value of the transmission tower includes taking the inclination of the tower as an input parameter of the tower vulnerability assessment model; when the inclination of the tower reaches the maximum allowable value, the vulnerability is 1; when the inclination of the tower is 0, the vulnerability is 0.

[0019] As a preferred embodiment of the vulnerability assessment method of power grid facilities based on the vulnerability assessment model described in the present invention, the vulnerability assessment of transmission towers includes dividing the vulnerability curve of towers at a constant wind volume into three categories: high vulnerability, medium vulnerability and low vulnerability according to the inclination of the towers.

[0020] Another object of the present invention is to provide a power grid facility vulnerability assessment system based on a vulnerability assessment model, which can analyze the deformation and failure mode of the tower, construct a vulnerability assessment model, generate a transmission tower vulnerability curve and perform dynamic correction to determine the vulnerability value, thereby realizing accurate assessment of the transmission tower under different environmental conditions, solving the problems of the existing vulnerability assessment methods that lack consideration of multivariate factors, static assessment results, and difficulty in accurately reflecting the actual vulnerability of the tower.

[0021] To solve the above technical problems, the present invention provides the following technical solutions: a vulnerability assessment method for power grid facilities based on a vulnerability assessment model, comprising a deformation and failure mode analysis module, a vulnerability assessment model construction module, a transmission tower vulnerability curve establishment module, a vulnerability correction module and a transmission tower vulnerability calculation module.

[0022] The deformation and failure mode analysis module is responsible for analyzing the deformation and failure mode of the tower and providing input parameters for building a vulnerability assessment model.

[0023] The vulnerability assessment model building module is responsible for building a mathematical model for assessing vulnerability.

[0024] The transmission tower vulnerability curve establishment module is responsible for generating a vulnerability curve using the Weibull distribution cumulative probability function.

[0025] The vulnerability correction module is responsible for adjusting the initially calculated vulnerability value using the modified Weibull distribution cumulative probability function.

[0026] The transmission tower vulnerability calculation module calculates the final vulnerability value of the tower according to the inclination, proportion and shape parameters of the tower.

[0027] A computer device includes a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the power grid facility vulnerability assessment method based on the vulnerability assessment model as described above are implemented.

[0028] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the power grid facility vulnerability assessment method based on the vulnerability assessment model as described above.

[0029] Beneficial effects of the present invention: The present invention improves the accuracy of vulnerability assessment through in-depth analysis of the deformation and failure mode of the tower, and makes up for the lack of understanding of the tower failure mechanism in the prior art, thereby improving the scientificity and reliability of the evaluation. At the same time, the present invention constructs a dynamic vulnerability curve based on the Weibull distribution and introduces a correction mechanism, so that the evaluation model can be adjusted in real time according to environmental changes, enhancing the dynamic adaptability of the model and effectively overcoming the limitations of the traditional static model. In addition, by introducing key variables such as the inclination of the tower, the present invention realizes the refined calculation of the vulnerability value, providing a more operational numerical basis for actual maintenance. Finally, the present invention divides the vulnerability level into three categories: high, medium and low, forming a scientific classification standard, so that operation and maintenance personnel can take targeted measures according to different levels, thereby improving the efficiency of risk management and resource allocation of power grid facilities, and ensuring the safe and stable operation of power grid facilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0031] Figure 1 An overall flow chart of a method for evaluating the vulnerability of power grid facilities based on a vulnerability evaluation model provided in the first embodiment of the present invention.

[0032] Figure 2 A graph showing the relationship between tower inclination and vulnerability based on Weibull cumulative probability distribution in a power grid facility vulnerability assessment method based on a vulnerability assessment model provided in the first embodiment of the present invention.

[0033] Figure 3 An overall framework diagram of a power grid facility vulnerability assessment system based on a vulnerability assessment model provided in the second embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0035] Example 1, reference Figure 1-2 , which is an embodiment of the present invention, provides a power grid facility vulnerability assessment method based on a vulnerability assessment model, characterized in that:

[0036] S1: Analyze the deformation and failure mode of the tower.

[0037] The analysis of the deformation and failure mode of the tower includes deriving the tower failure mode based on relative deformation parameters.

[0038] S2: Construct a vulnerability assessment model.

[0039] The quantification of the vulnerability of mining collapse is determined by two factors: one is the ground collapse intensity I of mining collapse, and the other is the performance of the transmission tower in resisting ground collapse, that is, the vulnerability of the transmission tower R. These two factors need to be considered in the vulnerability evaluation model, which can be expressed by the function:

[0040] V=f(I,R)

[0041] Among them, I represents the ground collapse intensity caused by mining subsidence, and R represents the vulnerability of the transmission tower.

[0042] For the mining collapse in the study area, since the residents of the houses in the collapse area have been completely relocated, the damaged objects in this report are mainly transmission towers. For transmission towers, there is no damage to the transmission towers when there is no ground collapse. When the ground collapse deformation is large enough, the transmission towers will collapse completely. That is, when the ground collapse intensity is 0, the vulnerability is 0, and when the ground collapse intensity is 1, the vulnerability is 1. The vulnerability of the transmission tower increases with the increase of the ground collapse intensity. However, for low-intensity ground collapse, the vulnerability of the transmission tower increases slowly; when the ground collapse intensity level is medium, this level is also enough to cause most of the damage to the transmission tower, and the degree of damage to the transmission tower increases faster; when the ground collapse intensity reaches a high level, the vulnerability of the transmission tower increases slowly and tends to 1. That is, the overall vulnerability of the transmission tower is S-shaped.

[0043] S3: Establish the transmission tower vulnerability curve.

[0044] For special disaster-bearing objects such as towers, the inclination of transmission towers is used to characterize the intensity of ground collapse, and the Weibull cumulative probability distribution function is used to establish the vulnerability curve of transmission towers. Weibull distribution is a continuous probability distribution widely used in reliability analysis. It can use the probability value to easily infer the corresponding distribution parameters and is used in data processing of various life tests. Its probability density is:

[0045]

[0046] Among them, x represents the scale parameter, λ is the size parameter, and k represents the shape parameter.

[0047] Its cumulative distribution function is an extended exponential distribution function.

[0048]

[0049] A value of k < 1 indicates that the failure rate decreases over time. A value of k = 1 indicates that the failure rate is constant over time. A value of k > 1 indicates that the failure rate increases over time.

[0050] S4: Correct the vulnerability of the transmission tower and determine the vulnerability value of the transmission tower.

[0051] The inclination of the transmission tower is used as the collapse strength, and the relationship between the vulnerability of the transmission line tower and the collapse strength is fitted using the Weibull distribution. The surface settlement value is a cumulative value, and the cumulative distribution function is used for fitting calculation. The modified Weibull distribution of the vulnerability of the transmission line tower is defined as follows:

[0052]

[0053] Among them, E represents the vulnerability of the transmission line tower, and a represents the inclination of the transmission tower.

[0054] The inclination of the tower is used as the input parameter of the tower vulnerability evaluation model. When the inclination of the tower reaches the maximum allowable value, the vulnerability is 1, and when the inclination of the tower is 0, the vulnerability is 0. The Weibull cumulative function cannot be fitted based on the two endpoint values ​​of vulnerability of 0 and 1, so it is also necessary to obtain the corresponding relationship between the inclination state of the transmission tower and the vulnerability. At present, there is no relevant research or standard at home and abroad. For this reason, we combined the common judgment of the power industry professionals on the degree of damage to the towers, combined the current inclination monitoring data of the four towers 34#, 35#, 38#, and 39# with the tower damage characteristics, and on this basis, assigned a value to each tower. The specific assignment is shown in Table 1. Among them, although the inclination of the 38# tower is large, due to its wire reinforcement, the tower structure has not undergone obvious deformation. In order to ensure the accuracy of the vulnerability function, the tower data is eliminated in the subsequent vulnerability function fitting.

[0055] Table 1 Tower damage characteristics and vulnerability values

[0056]

[0057]

[0058] According to the corresponding relationship between the inclination of the tower and the vulnerability in Table 1, the shape parameter k and size parameter λ of the physical vulnerability of the transmission tower are fitted by the least squares method based on the Weibull cumulative distribution function to obtain the transmission tower vulnerability curve. The fitting results are shown in Figure 2 .

[0059] The tower inclination vulnerability function obtained by fitting is:

[0060]

[0061] Among them, the shape parameter k is 5.3801, the size parameter λ is 0.6423, and the fitting accuracy is 0.99, indicating that the fitting effect is excellent. From the fragility curve, it can be seen that when the inclination of the transmission tower is less than 0.2°, the fragility of the tower is almost 0; when the inclination of the transmission tower is greater than 0.2°, the fragility of the tower shows an exponential increase trend; when the inclination of the transmission tower is greater than 0.8°, the fragility of the tower is 0.96~1.

[0062] S5: Evaluate the vulnerability of transmission towers based on the vulnerability values ​​of transmission towers.

[0063] In order to meet the risk warning needs of transmission towers in collapse areas, the tower vulnerability curve of constant wind volume is calculated according to the tower.

[0064] The slope is divided into three categories: high vulnerability, medium vulnerability and low vulnerability. The specific classification thresholds are shown in Table 2.

[0065] Existing research lacks vulnerability assessment for transmission towers. Therefore, according to the evaluation model in this paper, the vulnerability of the tower can be evaluated by monitoring the inclination of the transmission tower through monitoring instruments to obtain the operating status of the tower. In addition to being applicable to slow-settling ground collapse, this model is also applicable to direct-contact transmission towers distributed in slow landslide areas.

[0066] Table 2 Transmission tower vulnerability classification table

[0067] Tower inclination θ(°) 0≤θ<0.4 0.4≤θ<0.7 0.7≤θ<1 Vulnerability Low vulnerability Medium Vulnerability High vulnerability

[0068] According to the vulnerability classification table, the vulnerability levels of the four transmission towers 34#, 35#, 38# and 39# in Bojiazhai are shown in Table 3.

[0069] Table 3 Ground collapse transmission tower vulnerability level

[0070] Tower number 34# 35# 38# 39# Vulnerability High vulnerability High vulnerability High vulnerability Medium Vulnerability

[0071] Example 2, reference Figure 2 , which is an embodiment of the present invention, provides a system for a vulnerability assessment method of power grid facilities based on a vulnerability assessment model, characterized in that it includes a deformation and failure mode analysis module 100, a vulnerability assessment model construction module 200, a transmission tower vulnerability curve establishment module 300, a vulnerability correction module 400 and a transmission tower vulnerability calculation module 500.

[0072] The deformation and failure mode analysis module 100 is responsible for analyzing the deformation and failure mode of the tower and providing input parameters for building a vulnerability assessment model.

[0073] The vulnerability assessment model building module 200 is responsible for building a mathematical model for assessing vulnerability.

[0074] The transmission tower vulnerability curve building module 300 is responsible for generating a vulnerability curve using the Weibull distribution cumulative probability function.

[0075] The vulnerability modification module 400 is responsible for adjusting the initially calculated vulnerability value using the modified Weibull distribution cumulative probability function.

[0076] The transmission tower vulnerability calculation module 500 calculates the final vulnerability value of the tower according to the inclination, proportion and shape parameters of the tower.

[0077] 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 method 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 code.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A vulnerability assessment method for power grid facilities based on a vulnerability assessment model, characterized in that: include: Analyze the deformation and failure mode of the tower; Construct vulnerability assessment model; Establishing transmission tower vulnerability curves; Correct the fragility of the transmission tower and determine the fragility value of the transmission tower; The vulnerability of transmission towers is evaluated based on their vulnerability values.

2. The method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model according to claim 1, characterized in that: The analyzing of the deformation and failure mode of the pole tower includes obtaining the failure mode of the pole tower based on relative deformation parameters.

3. The method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model according to claim 2, characterized in that: The vulnerability assessment model is expressed as: V = f(I, R) Among them, I represents the ground collapse intensity caused by mining subsidence, and R represents the vulnerability of the transmission tower.

4. The method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model according to claim 3, characterized in that: The transmission tower vulnerability curve is established by using the Weibull distribution cumulative probability distribution function, in which the probability density is expressed as: Among them, x represents the scale parameter, λ is the size parameter, and k represents the shape parameter.

5. The method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model according to claim 4, characterized in that: The modification of the transmission tower vulnerability includes selecting a cumulative distribution function for fitting and calculating the modified Weibull distribution of the transmission line tower vulnerability. The definition is as follows: Among them, E represents the vulnerability of the transmission line tower, and a represents the inclination of the transmission tower.

6. The method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model according to claim 5, characterized in that: Determining the transmission tower vulnerability value includes using the tower inclination as an input parameter of the tower vulnerability evaluation model. When the tower inclination reaches the maximum allowable value, the vulnerability is 1, and when the tower inclination is 0, the vulnerability is 0.

7. The method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model according to claim 6, characterized in that: The transmission tower vulnerability evaluation includes dividing the tower vulnerability curves of a constant wind volume into three categories of high vulnerability, medium vulnerability and low vulnerability according to the inclination of the tower.

8. A system using the vulnerability assessment method for power grid facilities based on the vulnerability assessment model as claimed in any one of claims 1 to 7, characterized in that: It comprises a deformation failure mode analysis module (100), a vulnerability assessment model construction module (200), a transmission tower vulnerability curve establishment module (300), a vulnerability correction module (400) and a transmission tower vulnerability calculation module (500); The deformation and failure mode analysis module (100) is responsible for analyzing the deformation and failure mode of the tower and providing input parameters for constructing a vulnerability assessment model; The vulnerability assessment model building module (200) is responsible for building a mathematical model for assessing vulnerability; The transmission tower vulnerability curve establishment module (300) is responsible for generating a vulnerability curve using a Weibull distribution cumulative probability function; The vulnerability correction module (400) is responsible for adjusting the initially calculated vulnerability value using a modified Weibull distribution cumulative probability function; The transmission tower vulnerability calculation module (500) calculates the final vulnerability value of the tower according to the inclination, proportion and shape parameters of the tower.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method for assessing the vulnerability of power grid facilities based on a vulnerability assessment model described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method for evaluating the vulnerability of power grid facilities based on the vulnerability evaluation model described in any one of claims 1 to 7 are implemented.

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