Method, device and equipment for evaluating failure probability of arrester valve piece and medium

Abstract

The application discloses a lightning arrester valve piece failure probability evaluation method, relates to the technical field of zinc oxide valve pieces of lightning arresters, and is used for solving the problem of inaccurate evaluation results. The method comprises the following steps: performing a thermal power consumption characteristic test on a zinc oxide valve piece to obtain an accelerated aging time; calculating the residual life of the valve piece by means of the Arrhenius model according to the accelerated aging time; calculating the reliability of the valve piece by means of a double-parameter Weibull distribution model according to the residual life and an operation life; and calculating the failure probability according to the reliability and the operation life. The application further discloses a lightning arrester valve piece failure probability evaluation device, an electronic device and a computer storage medium. The application makes the valve piece life evaluation result more accurate by means of the Arrhenius model combined with the double-parameter Weibull distribution model.

Description

Technical Field

[0001] This invention relates to the field of zinc oxide varistors for surge arresters, and more particularly to a method, apparatus, equipment, and medium for assessing the failure probability of surge arrester varistors. Background Technology

[0002] Surge arresters have functions such as reducing overvoltage amplitude and preventing overvoltage from damaging the insulation system of electrical equipment. They are widely used in power grid systems to ensure the safe operation of electrical equipment and power grid systems.

[0003] When surge arresters have been in use for a long time, the varistor plates will undergo thermal aging, increasing the resistive leakage current flowing through the varistor plates, leading to increased heat dissipation, and potentially causing thermal collapse or even explosion of the surge arrester. Therefore, existing technologies analyze surge arresters from the perspective of their general operating conditions to understand the aging and moisture absorption during the deterioration of the arrester's condition.

[0004] In light of this, researchers have paid close attention to the assessment of valve plate service life, conducting extensive experiments and studies. Existing methods for evaluating valve plate service life are based on electrical quantities described in the GB11032-2020 standard, primarily including the total current and resistive current of surge arresters or resistors. These electrical quantities provide some assistance to personnel in assessing the aging status of surge arresters; however, these quantities often exhibit a "crescent effect," meaning that these parameters only show significant changes after the valve plate has aged to a certain extent. Before this "crescent point," test and analysis results meet the requirements of relevant standards, which complicates the assessment of valve plate thermal aging life and failure probability. Therefore, existing technologies cannot solve the aforementioned technical problems. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, one of the objectives of this invention is to provide a method for evaluating the failure probability of surge arrester valve plates, which predicts the failure probability of valve plates by testing thermal power dissipation performance and then accelerating the aging time.

[0006] One of the objectives of this invention is achieved through the following technical solution:

[0007] A method for assessing the failure probability of surge arrester valve plates includes the following steps:

[0008] The thermal power consumption characteristics of zinc oxide valve plates were tested to obtain the accelerated aging time.

[0009] The remaining lifespan of the valve plate is calculated using the Arrenius model based on the accelerated aging time.

[0010] Based on the remaining lifespan and operating years, the valve plate reliability is calculated using a two-parameter Weibull distribution model.

[0011] The probability of failure is calculated based on the reliability and the number of years of operation.

[0012] Furthermore, the thermal dissipation characteristics of the zinc oxide valve plate were tested to obtain the accelerated aging time, including:

[0013] Apply a continuous AC operating voltage to the valve plate and calculate the heat dissipation;

[0014] When the thermal power consumption reaches the initial value of 1.1Ps, the corresponding accelerated aging time is recorded.

[0015] Furthermore, the thermal power consumption characteristics include the fundamental effective value Ir of the valve plate's resistive current and the thermal power consumption aging curve Pr.

[0016] Furthermore, according to the accelerated aging time t h Calculating the remaining lifespan of the valve plate includes the following steps:

[0017] Calculate the thermal acceleration factor AF of the Arrenius model;

[0018] Based on the thermal acceleration factor and the accelerated aging time t h Calculate the remaining lifespan t of the valve plate s , satisfying t s =t h *AF.

[0019] Furthermore, based on the remaining lifespan and operating years, the valve plate reliability is calculated, including the following steps:

[0020] Based on the two-parameter Weibull distribution model, the probability distribution function F(t) is calculated, satisfying:

[0021] Where t is the service life of the valve plate, and α and β are the two parameters in the Weibull distribution model;

[0022] Calculate the valve plate reliability R(t), which satisfies: R(t) = 1 - F(t).

[0023] Furthermore, in the two-parameter Weibull distribution model, the position rank F(t) i The calculation of ) satisfies: Where i is the sample number of the zinc oxide valve plate arranged according to its equivalent service life, and t i To accelerate the equivalent operating years under aging conditions, n represents the number of zinc oxide valve plate samples.

[0024] Furthermore, based on the reliability and the service life, the failure probability λ(t) is calculated, satisfying:

[0025] The second objective of this invention is to provide a surge arrester valve plate failure probability assessment device, which estimates the valve plate lifespan to obtain the failure probability.

[0026] The second objective of this invention is achieved by the following technical solution:

[0027] A surge arrester valve failure probability assessment device, comprising:

[0028] The test module is used to test the thermal power consumption characteristics of zinc oxide valve plates and obtain the accelerated aging time.

[0029] The calculation module is used to calculate the remaining life of the valve plate using the Arrenius model based on the accelerated aging time; calculate the reliability of the valve plate using the two-parameter Weibull distribution model based on the remaining life and the number of years of operation; and calculate the failure probability based on the reliability and the number of years of operation.

[0030] A third objective of this invention is to provide an electronic device for performing one of the objectives of the invention, comprising a processor, a storage medium, and a computer program, wherein the computer program is stored in the storage medium and, when executed by the processor, implements the above-mentioned method for assessing the failure probability of surge arrester valve plates.

[0031] A fourth objective of this invention is to provide a computer-readable storage medium storing one of the objectives of the invention, wherein a computer program is stored thereon, and when the computer program is executed by a processor, it implements the above-described method for assessing the failure probability of surge arrester valve plates.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] This invention calculates the remaining lifespan of valve plates by testing their thermal power consumption characteristics and by calculating their reliability, thereby assessing the service life and failure probability of the valve plates. It combines the Arrenius model and the two-parameter Weibull distribution model to improve the accuracy of the assessment. The invention provides high accuracy in assessing the thermal aging lifespan and failure probability of valve plates, which can help maintenance personnel accurately determine the relationship between the thermal aging lifespan and failure probability of valve plates, help to scientifically formulate equipment retirement plans, and ensure the safe and stable operation of the power grid. Attached Figure Description

[0034] Figure 1 This is a flowchart of the surge arrester valve plate failure probability assessment method in this embodiment;

[0035] Figure 2 This is a graph showing the relationship between service life and reliability obtained from the test in Example 1;

[0036] Figure 3 This is a graph showing the relationship between service life and failure probability obtained from the test in Example 1;

[0037] Figure 4 This is a structural block diagram of the surge arrester valve plate failure probability assessment device in Embodiment 2;

[0038] Figure 5 This is a structural block diagram of the electronic device in Embodiment 3. Detailed Implementation

[0039] The present invention will now be described in more detail with reference to the accompanying drawings. It should be noted that the following description of the present invention with reference to the accompanying drawings is merely illustrative and not restrictive. Various embodiments can be combined with each other to form other embodiments not shown in the following description.

[0040] Example 1

[0041] Example 1 provides a method for assessing the failure probability of surge arrester valve plates. The method aims to calculate the remaining life of the valve plates using the Arrenius model and derive the correlation between the service life and reliability of the valve plates using a two-parameter Weibull distribution model, thereby achieving probability assessment.

[0042] The Arrenius model used in this embodiment is the thermal acceleration factor Arrenius model. For zinc oxide valve plates, temperature is the absolutely primary factor affecting product aging and service life. Using the Arrenius model, derived solely considering the thermal acceleration factor effect, to describe the test results will yield predictions closer to the actual values, resulting in better simulation performance. The calculation formula is as follows:

[0043] AF=exp{(E a / K)×[1 / T u -1 / T s ]},

[0044] Where AF is the thermal acceleration factor, E a The activation energy is determined based on the specific valve plate performance and is typically between 0.3 eV and 1.2 eV. K is the Boltzmann constant, with a value of 8.617385 × 10⁻⁵. T u T represents the temperature value under operating conditions. s All temperature values ​​under accelerated aging test conditions are absolute temperature values, expressed in Kelvin (K).

[0045] Based on the above principles, please refer to Figure 1 As shown, a method for assessing the failure probability of a surge arrester valve plate includes the following steps:

[0046] S1. Test the thermal power consumption characteristics of the zinc oxide valve plate to obtain the accelerated aging time;

[0047] S1 specifically includes:

[0048] Apply a continuous AC operating voltage to the valve plate and calculate the heat dissipation;

[0049] When the thermal power consumption reaches the initial value of 1.1Ps, the corresponding accelerated aging time is recorded.

[0050] The aforementioned voltage can be applied to the valve plate using a valve plate AC / DC aging device. The valve plate AC / DC aging device includes an AC / DC voltage output power supply, an AC regulated power supply, a power control cabinet, a test chamber, and a control and analysis system. The initial thermal dissipation value refers to the thermal dissipation corresponding to 3 hours of accelerated aging. The aforementioned thermal dissipation characteristics include the valve plate's resistive current fundamental RMS value Ir and the thermal dissipation aging curve Pr.

[0051] The above-mentioned continuous operating voltage U is based on the valve plate DC 1mA reference voltage U. 1mA Confirmed, the calculation formula is:

[0052] U = U 1mA / √2×0.9, where 0.9 is the surge arrester load factor.

[0053] In the specific testing process, multiple valve plates can be tested simultaneously to increase accuracy. For example, 15 valve plates can be placed in a test chamber simultaneously, and a continuous AC operating voltage U can be applied to the valve plates through 15 electrodes, while the temperature inside the test chamber is kept constant at 135℃. By calculating the product of Ir and U, the thermal power consumption characteristics of the valve plates can be obtained in real time. Table 1 below shows the test results of the 15 selected valve plates.

[0054] Table 1

[0055]

[0056] S2, based on the accelerated aging time t h The remaining lifespan of the valve plate is calculated using the Arrenius model;

[0057] S2 specifically includes the following steps:

[0058] Calculate the thermal acceleration factor AF of the Arrenius model;

[0059] Based on the thermal acceleration factor and the accelerated aging time t h Calculate the remaining lifespan t of the valve plate s , satisfying t s =t h *AF. As shown in Table 1, the remaining life of the valve plate exhibits significant dispersion, with the remaining life t... s The duration varies from 1 year to more than 10 years.

[0060] With E a =0.6eV, T u =298K,T sTaking 408K as an example, calculate the thermal acceleration factor:

[0061] S3. Calculate the valve plate reliability using a two-parameter Weibull distribution model based on the remaining lifespan and operating years.

[0062] S3 specifically includes: calculating the probability distribution function F(t) based on the two-parameter Weibull distribution model, satisfying:

[0063] Where t is the service life of the valve plate, and α and β are the two parameters in the Weibull distribution model;

[0064] In this embodiment, the two-parameter Weibull distribution model is calculated by calculating the median rank. Specifically, the median rank F(t) of the two-parameter Weibull distribution model is... i The calculation of ) satisfies: Where i is the sample number of the zinc oxide valve plate arranged according to its equivalent service life, and t i To accelerate the equivalent service life under aging conditions, n represents the number of zinc oxide valve plate samples. Taking Table 1 as an example, after conducting thermal power consumption tests on 15 valve plates, 9 valid data points were generated, therefore n = 9.

[0065] Calculate the valve plate reliability R(t), which satisfies: R(t) = 1 - F(t).

[0066] In the above formula, the calculation of F(t) can be transformed into:

[0067] make x = lnt, resulting in the linear function y = βx - βlnα, where α and β are obtained from the experimental data through least squares regression: α = 25.8536, β = 6.9402.

[0068] The correlation coefficient method was used to test the correlation of the Weibull distribution. The function is the linear function mentioned above. The correlation coefficient was 0.9406. Obviously, the test results obtained by this method are significantly correlated with the valve plate life.

[0069] Based on the data in Table 1, and referring to... Figure 2 As shown in the graph of the relationship between service life and reliability, reliability declines very slowly in the early stage of aging (before 12 years), accelerates in the middle stage of aging (12-25 years), and declines rapidly in the late stage of aging (after 25 years).

[0070] S4. Calculate the failure probability based on the reliability and the service life.

[0071] In S4, the failure probability λ(t) is calculated based on the reliability and the service life, satisfying:

[0072] Based on the data in Table 1, the relationship between service life and failure probability is shown in the following graph. Figure 3 As shown, it can be seen that the failure probability gradually increases with the increase of the operating years, and the failure probability in the early stage of operation remains at a low level, with no early failure.

[0073] In summary, based on physical testing, the failure probability assessment method described in this embodiment has high accuracy, solves the problem of inaccurate test results caused by the "inflection point effect," and is highly practical.

[0074] Example 2

[0075] Example 2 discloses a device corresponding to the surge arrester valve plate failure probability assessment method of the above embodiments. It is a virtual device structure of the above embodiments. Please refer to... Figure 4 As shown, it includes:

[0076] Test module 210 is used to test the thermal power consumption characteristics of zinc oxide valve plates and obtain the accelerated aging time.

[0077] The calculation module 220 is used to calculate the remaining life of the valve plate using the Arrenius model based on the accelerated aging time; calculate the reliability of the valve plate using the two-parameter Weibull distribution model based on the remaining life and the number of years of operation; and calculate the failure probability based on the reliability and the number of years of operation.

[0078] Preferably, the zinc oxide valve plate is subjected to thermal power consumption characteristic testing to obtain accelerated aging time, including:

[0079] Apply a continuous AC operating voltage to the valve plate and calculate the heat dissipation;

[0080] When the thermal power consumption reaches the initial value of 1.1Ps, the corresponding accelerated aging time is recorded.

[0081] Preferably, calculating the remaining lifespan of the valve plate based on the accelerated aging time includes the following steps:

[0082] Calculate the thermal acceleration factor AF of the Arrenius model;

[0083] Based on the thermal acceleration factor and the accelerated aging time t h Calculate the remaining lifespan t of the valve plate s , satisfying t s =t h *AF.

[0084] Preferably, the valve plate reliability is calculated based on the remaining lifespan and service life, including the following steps:

[0085] Based on the two-parameter Weibull distribution model, the probability distribution function F(t) is calculated, satisfying:

[0086] Where t is the service life of the valve plate, and α and β are the two parameters in the Weibull distribution model;

[0087] Calculate the valve plate reliability R(t), which satisfies: R(t) = 1 - F(t).

[0088] Preferably, the failure probability λ(t) is calculated based on the reliability and the service life, satisfying:

[0089] Example 3

[0090] Figure 5 This is a schematic diagram of the structure of an electronic device provided in Embodiment 3 of the present invention, as shown below. Figure 5 As shown, the electronic device includes a processor 310, a memory 320, an input device 330, and an output device 340; the number of processors 310 in the computer device can be one or more. Figure 5 Taking a processor 310 as an example; the processor 310, memory 320, input device 330, and output device 340 in the electronic device can be connected via a bus or other means. Figure 5 Taking the example of a connection between China and Israel via a bus.

[0091] The memory 320, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as the program instructions / modules corresponding to the surge arrester valve failure probability assessment method in this embodiment of the invention. The processor 310 executes various functional applications and data processing of the electronic device by running the software programs, instructions, and modules stored in the memory 320, thereby implementing the surge arrester valve failure probability assessment method of Embodiment 1 above.

[0092] The memory 320 may primarily include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a given function; the data storage area may store data created based on terminal usage. Furthermore, the memory 320 may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, the memory 320 may further include memory remotely located relative to the processor 310, which can be connected to the electronic device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0093] The input device 330 can be used to receive input user identification information, valve plate data, and detection data, etc. The output device 340 may include a display screen or other display device.

[0094] Example 4

[0095] Embodiment 4 of the present invention also provides a storage medium containing computer-executable instructions, which can be used by a computer to execute a method for assessing the failure probability of a surge arrester valve plate, the method comprising:

[0096] The thermal power consumption characteristics of zinc oxide valve plates were tested to obtain the accelerated aging time.

[0097] The remaining lifespan of the valve plate is calculated using the Arrenius model based on the accelerated aging time.

[0098] Based on the remaining lifespan and operating years, the valve plate reliability is calculated using a two-parameter Weibull distribution model.

[0099] The probability of failure is calculated based on the reliability and the number of years of operation.

[0100] Of course, the computer-executable instructions provided in the embodiments of the present invention are not limited to the method operations described above, but can also perform related operations in the surge arrester valve plate failure probability assessment method provided in any embodiment of the present invention.

[0101] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause an electronic device (which may be a mobile phone, personal computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0102] It is worth noting that in the embodiments of the above-mentioned surge arrester valve plate failure probability assessment method and device, the various units and modules included are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be achieved; in addition, the specific names of each functional unit are only for easy differentiation and are not used to limit the scope of protection of the present invention.

[0103] For those skilled in the art, various other corresponding changes and modifications can be made based on the technical solutions and concepts described above, and all such changes and modifications should fall within the protection scope of the claims of this invention.

Claims

1. A method for assessing the failure probability of surge arrester valve plates, characterized in that, Includes the following steps: The thermal power consumption characteristics of zinc oxide valve plates were tested to obtain the accelerated aging time. The remaining lifespan of the valve plate is calculated using the Arrenius model based on the accelerated aging time t; h Calculating the remaining lifespan of the valve plate includes the following steps: Calculate the thermal acceleration factor AF of the Arrenius model; Based on the thermal acceleration factor and the accelerated aging time t h Calculate the remaining lifespan t of the valve plate s , satisfying t s =t h *AF; Based on the remaining lifespan and operating years, the valve plate reliability is calculated using a two-parameter Weibull distribution model; including: Based on the two-parameter Weibull distribution model, the probability distribution function F(t) is calculated, satisfying: Where t is the number of years of operation, and α and β are the two parameters in the Weibull distribution model; Calculate the valve plate reliability R(t), which satisfies: R(t) = 1 - F(t); The failure probability λ(t) is calculated based on the reliability and the service life, satisfying:

2. The method for assessing the failure probability of surge arrester valve plates as described in claim 1, characterized in that, Thermal dissipation characteristics of zinc oxide valve plates were tested to obtain accelerated aging time, including: Apply a continuous AC operating voltage to the valve plate and calculate the heat dissipation; When the thermal power consumption reaches the initial value of 1.1Ps, the corresponding accelerated aging time is recorded.

3. The method for assessing the failure probability of surge arrester valve plates as described in claim 1 or 2, characterized in that, The thermal power consumption characteristics include the fundamental effective value of the resistive current of the valve plate, Ir, and the thermal power consumption aging curve, Pr.

4. The method for assessing the failure probability of surge arrester valve plates as described in claim 1, characterized in that, The rank F(t) in the two-parameter Weibull distribution model i The calculation of ) satisfies: Where i is the sample number of the zinc oxide valve plate arranged according to its equivalent service life, and t i To accelerate the equivalent operating years under aging conditions, n represents the number of zinc oxide valve plate samples.

5. A device for assessing the failure probability of surge arrester valve plates, characterized in that, It includes: The test module is used to test the thermal power consumption characteristics of zinc oxide valve plates and obtain the accelerated aging time. The calculation module is used to calculate the remaining life of the valve plate using the Arrenius model based on the accelerated aging time. According to the accelerated aging time t h Calculating the remaining lifespan of the valve plate includes the following steps: Calculate the thermal acceleration factor AF of the Arrenius model; Based on the thermal acceleration factor and the accelerated aging time t h Calculate the remaining lifespan t of the valve plate s , satisfying t s =t h *AF; Based on the remaining lifespan and operating years, the valve plate reliability is calculated using a two-parameter Weibull distribution model; including: Based on the two-parameter Weibull distribution model, the probability distribution function F(t) is calculated, satisfying: Where t is the service life of the valve plate, and α and β are the two parameters in the Weibull distribution model; Calculate the valve plate reliability R(t), which satisfies: R(t) = 1 - F(t); The failure probability λ(t) is calculated based on the reliability and the service life, satisfying:

6. An electronic device comprising a processor, a storage medium, and a computer program, wherein the computer program is stored in the storage medium, characterized in that, When the computer program is executed by the processor, it implements the surge arrester valve plate failure probability assessment method according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the surge arrester valve plate failure probability assessment method according to any one of claims 1 to 4.

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