A method of cable replacement selection

Abstract

The application provides a replacement cable selection method, relates to the technical field of cable replacement, and comprises the following steps: calculating the conductor shielding field intensity of a cable to be replaced and the insulation shielding field intensity of the cable to be replaced; performing preliminary screening from existing selectable cables to obtain a sample cable set; obtaining all types of performance evaluation values of each sample cable in each monitoring period; constructing a performance comprehensive evaluation matrix corresponding to each sample cable in each monitoring period; calculating the comprehensive performance evaluation value of each sample cable; and selecting a replacement cable based on the comprehensive performance evaluation value of each sample cable. The application selects the replacement cable through systematic steps, ensures the scientificity of the selection process of the replacement cable, fully considers the electrical performance parameters of the cable to be replaced, focuses on the influence of actual parameters and limitation conditions of a construction environment on the replacement cable, reduces the possibility of cable failure, and fully considers the total cost of laying and later maintenance in the cable selection process, so that the operation cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of cable replacement technology, and specifically relates to a method for selecting replacement cables. Background Technology

[0002] As a key component of modern social infrastructure and energy transmission, cables face the need for continuous updating and replacement with the advancement of technology and social development. Traditional cable replacement methods often lack systematic steps, leading to reliance on experience or single standards when selecting replacement cables. This can easily result in cable performance not matching the actual application environment, thus affecting the cable's performance and safety. Furthermore, existing methods may not fully consider the electrical performance parameters of the cable to be replaced, such as conductor and insulation shielding field strength, making the selected cable unable to meet specific electrical performance requirements and increasing the risk of failure. When selecting replacement cables, existing technologies may not adequately consider the actual parameters and limitations of the construction environment, resulting in cables that are not well-suited for specific environments and increasing the likelihood of cable failure. Finally, in the cable selection process, existing technologies may not fully consider the total cost of laying and subsequent maintenance, easily leading to the final selected cable being economically disadvantageous and increasing operating costs. Summary of the Invention

[0003] The present invention provides a method for selecting replacement cables to solve at least one of the technical problems mentioned above.

[0004] To address the aforementioned technical problems, this invention discloses a method for selecting replacement cables, comprising the following steps:

[0005] S1. Obtain the rated parameters of the cable to be replaced, and calculate the conductor shielding field strength and the insulation shielding field strength of the cable to be replaced based on the rated parameters of the cable to be replaced.

[0006] S2. Collect environmental parameters of the construction environment and determine the limiting conditions under the current construction environment based on the collection results;

[0007] S3. Based on the rated parameters of the cable to be replaced, the conductor shielding field strength of the cable to be replaced, the insulation shielding field strength of the cable to be replaced, and the limiting conditions under the current construction environment, a preliminary screening is conducted from the existing available cables to obtain a sample cable set.

[0008] S4. Conduct performance tests on the sample cables and collect the physical parameters of each sample cable during each monitoring cycle in the test process. Based on the physical parameters of each sample cable during each monitoring cycle in the test process, obtain all types of performance evaluation values ​​for each sample cable in each monitoring cycle.

[0009] S5. Based on the physical parameters of each sample cable in each monitoring cycle during the test and the performance evaluation values ​​of all types in each monitoring cycle, construct a comprehensive performance evaluation matrix for each sample cable in each monitoring cycle.

[0010] S6. Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, calculate the comprehensive performance evaluation value of each sample cable, and select a replacement cable based on the comprehensive performance evaluation value of each sample cable.

[0011] Preferably, the rated parameters of the cable to be replaced are obtained, and the conductor shielding field strength and insulation shielding field strength of the cable to be replaced are calculated based on the rated parameters of the cable to be replaced, including:

[0012] Conductor shielding field strength of the cable to be replaced:

[0013]

[0014] Insulation shielding field strength of the cable to be replaced:

[0015] Among them, E max E represents the conductor shielding field strength of the cable to be replaced. min U0 is the insulation shielding field strength of the cable to be replaced, U0 is the rated voltage of the cable to be replaced, D is the outer radius of the insulation of the cable to be replaced, d is the inner radius of the insulation of the cable to be replaced, and Ln is the logarithm to the base e.

[0016] Preferably, environmental parameters of the construction environment are collected, and the limiting conditions of the current construction environment are determined based on the collection results, including:

[0017] S21. Collect data on the temperature, humidity, acidity / alkalinity of the cable contact environment, and external forces acting on the cable in the construction environment.

[0018] S22. Based on the collected data on the construction environment temperature, humidity, cable contact environment pH, cable external force, and preset reference environment temperature, preset reference environment humidity, preset reference cable contact environment pH, and preset reference cable external force, determine the limiting conditions under the current construction environment.

[0019] S23. Based on the constraints under the current construction environment, provide the upper limit value of the constraints.

[0020] Preferably, step S22 includes:

[0021] Compare the differences between the temperature of the construction environment and the preset reference temperature, the humidity of the construction environment and the preset reference humidity, the pH of the cable contact environment in the construction environment and the pH of the cable contact environment in the preset reference, and the environmental external force on the cable in the construction environment and the environmental external force on the cable in the preset reference.

[0022] If the temperature difference between the construction environment and the preset reference environment temperature is greater than the preset temperature difference, the temperature adaptability of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the temperature adaptability range of the cable.

[0023] If the difference between the construction environment humidity and the preset reference environment humidity is greater than the preset humidity difference, the waterproof performance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the range of the cable's waterproof performance.

[0024] If the difference between the acidity / alkalinity of the cable contact environment during construction and the acidity / alkalinity of the preset reference cable contact environment is greater than the preset acidity / alkalinity difference, then the corrosion resistance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the range of the cable's corrosion resistance.

[0025] If the difference between the environmental force exerted on the cable in the construction environment and the environmental force exerted on the preset reference cable is greater than the preset difference, then the mechanical strength performance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the mechanical strength range of the cable.

[0026] Preferably, based on the rated parameters of the cable to be replaced, the conductor shielding field strength of the cable to be replaced, the insulation shielding field strength of the cable to be replaced, and the limiting conditions under the current construction environment, a preliminary screening is conducted from the existing available cables to obtain a sample cable set, including:

[0027] S31. Select a cable with the same rated parameters as the cable to be replaced from the existing available cables as a preliminary screening cable;

[0028] S32. Select cables from the first preliminary screening cables that have higher conductor shielding field strength and insulation shielding field strength than the cables to be replaced, and use them as second preliminary screening cables.

[0029] S33. Select cables that meet the upper limit of the restriction conditions from the secondary preliminary screening cables and use them as a sample cable set.

[0030] Preferably, step S4 includes:

[0031] S41. Lay each sample cable in the pre-arranged simulated construction environment using the same laying method as the replacement cable, and simulate the transmission signal during the actual working process of the cable to be replaced. Connect each sample cable to the energy spectrum analyzer, moisture tester, and insulation resistance tester.

[0032] The environmental parameters of the simulated construction environment are the same as those of the laying environment of the cable to be replaced.

[0033] S42. Collect the percentage of copper and oxygen content of each sample cable in each monitoring cycle during the test using an energy dispersive spectroscopy analyzer;

[0034] The moisture content of each sample cable joint end was collected using a moisture meter during each monitoring period of the test.

[0035] The insulation resistance change of each sample cable was collected during each monitoring cycle of the test using an insulation resistance tester.

[0036] S43. Input the percentage of copper and oxygen content, the moisture content of each sample cable joint end, and the change in insulation resistance of each sample cable in each monitoring cycle during the test into the trained cable oxidation resistance evaluation model, cable waterproof performance evaluation model, and cable aging performance evaluation model, respectively, to obtain the cable oxidation resistance evaluation value, cable waterproof performance evaluation value, and cable aging performance evaluation value for each sample cable in each monitoring cycle.

[0037] Preferably, based on the physical parameters of each sample cable during each monitoring cycle and the performance evaluation values ​​of all types for each monitoring cycle, a comprehensive performance evaluation matrix is ​​constructed for each sample cable for each monitoring cycle:

[0038] in, Let a be the comprehensive performance evaluation matrix corresponding to the i-th sample cable. i1 Let a be the percentage of copper and oxygen content in the i-th sample cable during the first monitoring cycle. i2 Let a be the percentage of copper and oxygen content in the second monitoring cycle of the i-th sample cable. in Let b be the percentage of copper and oxygen content in the i-th sample cable during the n-th monitoring cycle. i1 Let b be the moisture content at the cable joint end of the i-th sample cable during the first monitoring cycle. i2 Let b be the moisture content at the cable joint end of the i-th sample cable during the second monitoring cycle. in Let c be the moisture content at the cable joint end of the i-th sample cable during the n-th monitoring cycle. i1 Let c be the change in insulation resistance of the i-th sample cable during the first monitoring cycle. i2 Let c be the change in insulation resistance of the i-th sample cable during the second monitoring cycle. in Let A be the change in insulation resistance of the i-th sample cable during the n-th monitoring period. i1 Let A be the evaluation value of the cable's oxidation resistance for the i-th sample cable in the first monitoring cycle. i2 A represents the evaluation value of the cable's oxidation resistance in the second monitoring cycle for the i-th sample cable. in B represents the evaluation value of the cable's oxidation resistance in the nth monitoring cycle for the i-th sample cable. i1B represents the cable waterproof performance evaluation value for the i-th sample cable in the first monitoring cycle. i2 B represents the cable waterproof performance evaluation value for the i-th sample cable in the second monitoring cycle. in C represents the cable waterproof performance evaluation value for the i-th sample cable in the n-th monitoring period. i1 C represents the cable aging performance evaluation value for the i-th sample cable in the first monitoring cycle. i2 C represents the cable aging performance evaluation value for the i-th sample cable in the second monitoring cycle. in This is the cable aging performance evaluation value for the i-th sample cable in the nth monitoring cycle.

[0039] Preferably, based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, a comprehensive performance evaluation value for each sample cable is calculated, and a replacement cable is selected based on the comprehensive performance evaluation value of each sample cable, including:

[0040] S61. Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, obtain the main influence value and the secondary influence value of the comprehensive performance evaluation value of each sample cable.

[0041] S62. Calculate the comprehensive performance evaluation value of each sample cable based on the main influence value and the secondary influence value of the comprehensive performance evaluation value of each sample cable.

[0042] S63. Compare the comprehensive performance evaluation values ​​of each sample cable, select the two sample cables with the highest comprehensive performance evaluation values, compare the total cost of laying and subsequent maintenance of the two sample cables, and if the difference between the total cost of laying and subsequent maintenance of the two sample cables is less than the preset cost difference, then select the sample cable with the highest ranking as the replacement cable.

[0043] Otherwise, select the second-ranked sample cable as the replacement cable.

[0044] Preferably, step S61 includes:

[0045] In the comprehensive performance evaluation matrix elements corresponding to each monitoring cycle of each sample cable, the performance evaluation values ​​of each type and their corresponding monitoring data are deleted to obtain the evaluation matrix of each type of performance.

[0046] If the rank of the evaluation matrix for each type of performance of the sample cable is greater than the preset threshold of the corresponding type performance evaluation value, then the performance evaluation value of the corresponding type in the last cycle of the sample cable is taken as the main influencing value of the comprehensive performance evaluation value; otherwise, it is taken as the secondary influencing value of the comprehensive performance evaluation value.

[0047] Preferably, the overall performance evaluation value of each sample cable is calculated based on the primary influence value and the secondary influence value of the overall performance evaluation value:

[0048] in, Let X be the comprehensive performance evaluation value of the i-th sample cable, u be the total number of main influencing values ​​of the comprehensive performance evaluation value of the i-th sample cable, and X be the total number of influencing values. j Let Y be the j-th major influencing value of the comprehensive performance evaluation of the i-th sample cable, where e is a natural number with a value of 2.71. k This is the secondary influence value of the kth comprehensive performance evaluation value of the i-th sample cable.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] This invention provides a systematic approach to selecting replacement cables, avoiding reliance on experience or a single standard. Through clearly defined steps, the selection process is scientific and accurate, improving cable performance and safety. It fully considers the electrical performance parameters of the cable to be replaced, such as conductor and insulation shielding field strength, to ensure the selected cable meets specific electrical performance requirements. This reduces the risk of failure, ensures the reliability of the cable system, and emphasizes the impact of actual environmental parameters and limitations on the replacement cable, ensuring the selected cable is suitable for specific environments, reducing the possibility of cable failure, and improving system reliability. The total cost of laying and subsequent maintenance is fully considered during cable selection. By comprehensively considering economic factors, the invention selects the more cost-effective replacement cable, thereby reducing operating costs. Attached Figure Description

[0051] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0052] Figure 1 This is a flowchart of a replacement cable selection method proposed in this invention. Detailed Implementation

[0053] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0054] Furthermore, in this invention, the use of terms such as "first" and "second" is for descriptive purposes only and does not specifically refer to any order or sequence, nor is it intended to limit the invention. They are merely used to distinguish components or operations described using the same technical terms and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions and features of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If a combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0055] The present invention provides the following embodiments.

[0056] Example 1

[0057] This invention provides a method for selecting replacement cables, such as... Figure 1 As shown, it includes the following steps:

[0058] S1. Obtain the rated parameters of the cable to be replaced, and calculate the conductor shielding field strength and the insulation shielding field strength of the cable to be replaced based on the rated parameters of the cable to be replaced.

[0059] S2. Collect environmental parameters of the construction environment and determine the limiting conditions under the current construction environment based on the collection results;

[0060] S3. Based on the rated parameters of the cable to be replaced, the conductor shielding field strength of the cable to be replaced, the insulation shielding field strength of the cable to be replaced, and the limiting conditions under the current construction environment, a preliminary screening is conducted from the existing available cables to obtain a sample cable set.

[0061] S4. Conduct performance tests on the sample cables and collect the physical parameters of each sample cable during each monitoring cycle in the test process. Based on the physical parameters of each sample cable during each monitoring cycle in the test process, obtain all types of performance evaluation values ​​for each sample cable in each monitoring cycle.

[0062] S5. Based on the physical parameters of each sample cable in each monitoring cycle during the test and the performance evaluation values ​​of all types in each monitoring cycle, construct a comprehensive performance evaluation matrix for each sample cable in each monitoring cycle.

[0063] S6. Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, calculate the comprehensive performance evaluation value of each sample cable, and select a replacement cable based on the comprehensive performance evaluation value of each sample cable.

[0064] In this embodiment, the rated parameters of the cable to be replaced include rated voltage, inner insulation radius, and outer insulation radius.

[0065] In this embodiment, the environmental parameters of the construction environment include the temperature and humidity of the construction environment, the acidity or alkalinity of the cable contact environment, and the external forces exerted on the cable by the environment.

[0066] The working principle and beneficial effects of the above technical solution are as follows: Through systematic steps, this invention can effectively improve the accuracy and reliability of cable replacement. In the implementation process, the rated parameters of the cable to be replaced are first obtained, and its conductor and insulation shielding field strength are calculated to ensure that the newly selected cable can meet the corresponding electrical performance requirements. Subsequently, by collecting environmental parameters of the construction environment, the limiting conditions are evaluated to ensure the applicability of the selected cable in the specific environment. On this basis, combined with the preliminary screening of existing optional cables, a sample cable set is formed, and performance tests are conducted on it to obtain physical parameters and performance evaluation values. By constructing a comprehensive performance evaluation matrix, the comprehensive performance evaluation value of each sample cable is quantified, and a replacement cable with superior performance is selected, thereby achieving the purpose of optimizing cable selection, improving construction safety, and reducing subsequent maintenance costs.

[0067] This invention provides a systematic approach to selecting replacement cables, avoiding reliance on experience or a single standard. Through clearly defined steps, the selection process is scientific and accurate, improving cable performance and safety. It fully considers the electrical performance parameters of the cable to be replaced, such as conductor and insulation shielding field strength, to ensure the selected cable meets specific electrical performance requirements. This reduces the risk of failure, ensures the reliability of the cable system, and emphasizes the impact of actual environmental parameters and limitations on the replacement cable, ensuring the selected cable is suitable for specific environments, reducing the possibility of cable failure, and improving system reliability. The total cost of laying and subsequent maintenance is fully considered during cable selection. By comprehensively considering economic factors, the invention selects the more cost-effective replacement cable, thereby reducing operating costs.

[0068] Example 2

[0069] Based on Example 1, the rated parameters of the cable to be replaced are obtained, and the conductor shielding field strength and insulation shielding field strength of the cable to be replaced are calculated based on the rated parameters of the cable to be replaced, including:

[0070] Conductor shielding field strength of the cable to be replaced:

[0071]

[0072] Insulation shielding field strength of the cable to be replaced:

[0073] Among them, E maxE represents the conductor shielding field strength of the cable to be replaced. min U0 is the insulation shielding field strength of the cable to be replaced, U0 is the rated voltage of the cable to be replaced, D is the outer radius of the insulation of the cable to be replaced, d is the inner radius of the insulation of the cable to be replaced, and Ln is the logarithm to the base e.

[0074] The working principle and beneficial effects of the above technical solution are as follows: the conductor shielding field strength and insulation shielding field strength obtained by calculation can be used as one of the bases for selecting replacement cables. This calculation method can more accurately evaluate the electrical performance of the cable to be replaced, thereby guiding the selection of a more suitable replacement cable and improving the reliability and safety of the cable system.

[0075] Example 3

[0076] Based on Example 1, environmental parameters of the construction environment are collected, and the limiting conditions under the current construction environment are determined based on the collection results, including:

[0077] S21. Collect data on the temperature, humidity, acidity / alkalinity of the cable contact environment, and external forces acting on the cable in the construction environment.

[0078] S22. Based on the collected data on the construction environment temperature, humidity, cable contact environment pH, cable external force, and preset reference environment temperature, preset reference environment humidity, preset reference cable contact environment pH, and preset reference cable external force, determine the limiting conditions under the current construction environment.

[0079] S23. Based on the constraints under the current construction environment, provide the upper limit value of the constraints.

[0080] The working principle and beneficial effects of the above technical solution are as follows: by collecting and judging the parameters of the construction environment and giving the corresponding upper limit values ​​of the limiting conditions, the applicability and reliability of the cable to be replaced can be evaluated more accurately.

[0081] Example 4

[0082] Based on Example 3, step S22 includes:

[0083] Compare the differences between the temperature of the construction environment and the preset reference temperature, the humidity of the construction environment and the preset reference humidity, the pH of the cable contact environment in the construction environment and the pH of the cable contact environment in the preset reference, and the environmental external force on the cable in the construction environment and the environmental external force on the cable in the preset reference.

[0084] If the temperature difference between the construction environment and the preset reference environment temperature is greater than the preset temperature difference, the temperature adaptability of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the temperature adaptability range of the cable.

[0085] If the difference between the construction environment humidity and the preset reference environment humidity is greater than the preset humidity difference, the waterproof performance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the range of the cable's waterproof performance.

[0086] If the difference between the acidity / alkalinity of the cable contact environment during construction and the acidity / alkalinity of the preset reference cable contact environment is greater than the preset acidity / alkalinity difference, then the corrosion resistance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the range of the cable's corrosion resistance.

[0087] If the difference between the environmental force exerted on the cable in the construction environment and the environmental force exerted on the preset reference cable is greater than the preset difference, then the mechanical strength performance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the mechanical strength range of the cable.

[0088] The working principle and beneficial effects of the above technical solution are as follows: By comparing the temperature and humidity of the construction environment, the acidity and alkalinity of the cable contact environment, and the differences between the cable's environmental external force and the preset benchmark environment, the impact of various environmental factors on cable performance is systematically evaluated.

[0089] In step S22, if the temperature difference between the construction environment and the preset reference temperature exceeds the preset temperature difference, the cable's temperature adaptability is included as a limiting condition, and the upper limit of the limiting condition is set as the cable's temperature adaptability range; if the humidity difference between the construction environment and the reference humidity exceeds the preset humidity difference, the cable's waterproof performance becomes a limiting condition, and the upper limit is the cable's waterproof performance range; similarly, if the pH difference between the cable's contact environment and the pH difference exceeds the preset pH difference, the cable's corrosion resistance is considered a limiting condition, and the upper limit is set as its corrosion resistance range; finally, if the difference in the external forces exerted on the cable by the environment exceeds the preset external force difference, the cable's mechanical strength performance is one of the limiting conditions, and its upper limit is the cable's mechanical strength range.

[0090] This refined judgment and evaluation method can more comprehensively and accurately determine the impact of the construction environment on cable performance, thereby providing a more reliable basis for the selection of replacement cables, ensuring the applicability and safety of the newly selected cables in specific construction environments, and significantly improving the overall reliability and service life of the cable system.

[0091] Example 5

[0092] Based on Example 1, and taking into account the rated parameters of the cable to be replaced, the conductor shielding field strength of the cable to be replaced, the insulation shielding field strength of the cable to be replaced, and the limitations of the current construction environment, a preliminary screening is conducted from the available cables to obtain a sample cable set, including:

[0093] S31. Select a cable with the same rated parameters as the cable to be replaced from the existing available cables as a preliminary screening cable;

[0094] S32. Select cables from the first preliminary screening cables that have higher conductor shielding field strength and insulation shielding field strength than the cables to be replaced, and use them as second preliminary screening cables.

[0095] S33. Select cables that meet the upper limit of the restriction conditions from the secondary preliminary screening cables and use them as a sample cable set.

[0096] The working principle and beneficial effects of the above technical solution are as follows: Cables with the same rated parameters as the cable to be replaced are selected from the existing available cables as the first preliminary screening cables. This step ensures that the initially selected cables match the cable to be replaced in electrical specifications, laying the foundation for subsequent screening. Based on the first preliminary screening, cables with conductor shielding field strength and insulation shielding field strength both higher than the cable to be replaced are further selected as the second preliminary screening cables. This process ensures that the selected cables have a higher safety margin in shielding performance and can better adapt to possible electromagnetic interference. From the second preliminary screening cables, cables that meet the upper limit of the limiting conditions under the construction environment are selected to form the final sample cable set. By comprehensively considering the cable performance and the requirements of the construction environment, the selected sample cable set will be more applicable and reliable.

[0097] Example 6

[0098] Based on Example 1, step S4 includes:

[0099] S41. Lay each sample cable in the pre-arranged simulated construction environment using the same laying method as the replacement cable, and simulate the transmission signal during the actual working process of the cable to be replaced. Connect each sample cable to the energy spectrum analyzer, moisture tester, and insulation resistance tester.

[0100] The environmental parameters of the simulated construction environment are the same as those of the laying environment of the cable to be replaced.

[0101] S42. Collect the percentage of copper and oxygen content of each sample cable in each monitoring cycle during the test using an energy dispersive spectroscopy analyzer;

[0102] The moisture content of each sample cable joint end was collected using a moisture meter during each monitoring period of the test.

[0103] The insulation resistance change of each sample cable was collected during each monitoring cycle of the test using an insulation resistance tester.

[0104] S43. Input the percentage of copper and oxygen content, the moisture content of each sample cable joint end, and the change in insulation resistance of each sample cable in each monitoring cycle during the test into the trained cable oxidation resistance evaluation model, cable waterproof performance evaluation model, and cable aging performance evaluation model, respectively, to obtain the cable oxidation resistance evaluation value, cable waterproof performance evaluation value, and cable aging performance evaluation value for each sample cable in each monitoring cycle.

[0105] The working principle and beneficial effects of the above technical solution are as follows: Detailed evaluation of the copper-oxygen content, moisture content, and insulation resistance of each sample cable during the test process, thereby accurately assessing the cable's oxidation resistance, waterproof performance, and aging performance. These evaluation values ​​will provide an important reference for the final cable selection, ensuring that the selected cable can maintain stable and reliable performance during long-term use.

[0106] Example 7

[0107] Based on Example 6, and using the physical parameters of each sample cable during each monitoring cycle and the performance evaluation values ​​of all types for each monitoring cycle, a comprehensive performance evaluation matrix is ​​constructed for each sample cable for each monitoring cycle:

[0108] in, Let a be the comprehensive performance evaluation matrix corresponding to the i-th sample cable. i1 Let a be the percentage of copper and oxygen content in the i-th sample cable during the first monitoring cycle. i2 Let a be the percentage of copper and oxygen content in the second monitoring cycle of the i-th sample cable. in Let b be the percentage of copper and oxygen content in the i-th sample cable during the n-th monitoring cycle. i1 Let b be the moisture content at the cable joint end of the i-th sample cable during the first monitoring cycle. i2 Let b be the moisture content at the cable joint end of the i-th sample cable during the second monitoring cycle. in Let c be the moisture content at the cable joint end of the i-th sample cable during the n-th monitoring cycle. i1 Let c be the change in insulation resistance of the i-th sample cable during the first monitoring cycle. i2 Let c be the change in insulation resistance of the i-th sample cable during the second monitoring cycle. in Let A be the change in insulation resistance of the i-th sample cable during the n-th monitoring period. i1 Let A be the evaluation value of the cable's oxidation resistance for the i-th sample cable in the first monitoring cycle. i2 A represents the evaluation value of the cable's oxidation resistance in the second monitoring cycle for the i-th sample cable. inB represents the evaluation value of the cable's oxidation resistance in the nth monitoring cycle for the i-th sample cable. i1 B represents the cable waterproof performance evaluation value for the i-th sample cable in the first monitoring cycle. i2 B represents the cable waterproof performance evaluation value for the i-th sample cable in the second monitoring cycle. in C represents the cable waterproof performance evaluation value for the i-th sample cable in the n-th monitoring period. i1 C represents the cable aging performance evaluation value for the i-th sample cable in the first monitoring cycle. i2 C represents the cable aging performance evaluation value for the i-th sample cable in the second monitoring cycle. in This is the cable aging performance evaluation value for the i-th sample cable in the nth monitoring cycle.

[0109] The working principle and beneficial effects of the above technical solution are as follows: By constructing a comprehensive performance evaluation matrix, multiple performance indicators of each sample cable under different monitoring periods can be displayed intuitively. This comprehensive evaluation matrix helps researchers and engineers to more fully understand the performance of the sample cables and compare and evaluate them. Through the analysis and comparison of the matrix, the best-performing cable can be selected as a replacement cable, thereby improving the reliability and service life of the cable system.

[0110] Example 8

[0111] Based on Example 1, a comprehensive performance evaluation value for each sample cable is calculated using the comprehensive performance evaluation matrix corresponding to each monitoring cycle. Replacement cables are then selected based on the comprehensive performance evaluation value of each sample cable, including:

[0112] S61. Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, obtain the main influence value and the secondary influence value of the comprehensive performance evaluation value of each sample cable.

[0113] S62. Calculate the comprehensive performance evaluation value of each sample cable based on the main influence value and the secondary influence value of the comprehensive performance evaluation value of each sample cable.

[0114] S63. Compare the comprehensive performance evaluation values ​​of each sample cable, select the two sample cables with the highest comprehensive performance evaluation values, compare the total cost of laying and subsequent maintenance of the two sample cables, and if the difference between the total cost of laying and subsequent maintenance of the two sample cables is less than the preset cost difference, then select the sample cable with the highest ranking as the replacement cable.

[0115] Otherwise, select the second-ranked sample cable as the replacement cable.

[0116] Preferably, step S61 includes:

[0117] In the comprehensive performance evaluation matrix elements corresponding to each monitoring cycle of each sample cable, the performance evaluation values ​​of each type and their corresponding monitoring data are deleted to obtain the evaluation matrix of each type of performance.

[0118] If the rank of the evaluation matrix for each type of performance of the sample cable is greater than the preset threshold of the corresponding type performance evaluation value, then the performance evaluation value of the corresponding type in the last cycle of the sample cable is taken as the main influencing value of the comprehensive performance evaluation value; otherwise, it is taken as the secondary influencing value of the comprehensive performance evaluation value.

[0119] Preferably, the overall performance evaluation value of each sample cable is calculated based on the primary influence value and the secondary influence value of the overall performance evaluation value:

[0120] in, Let be the comprehensive performance evaluation value of the i-th sample cable, u be the total number of main influencing values ​​of the comprehensive performance evaluation value of the i-th sample cable, and χ be the total number of influencing values. j Let Y be the j-th major influencing value of the comprehensive performance evaluation of the i-th sample cable, where e is a natural number with a value of 2.71. k This is the secondary influence value of the kth comprehensive performance evaluation value of the i-th sample cable.

[0121] The working principle and beneficial effects of the above technical solution are as follows: First, based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, the main and secondary influence values ​​of the comprehensive performance evaluation value of each sample cable are determined. By deleting each performance evaluation value and its corresponding monitoring data in the comprehensive performance evaluation matrix of each sample cable, the evaluation matrix of each type of performance is obtained. According to the comparison result of the rank of each type of performance evaluation matrix with the preset threshold, the main and secondary influence values ​​of the comprehensive performance evaluation value of each sample cable are determined. Based on the main and secondary influence values ​​of the comprehensive performance evaluation value of each sample cable, the comprehensive performance evaluation value of each sample cable is calculated. According to the calculation method in formula (4), the main influence value and the secondary influence value are combined to obtain the comprehensive performance evaluation value of each sample cable. The comprehensive performance evaluation values ​​of each sample cable are compared, and the sample cables with the top two comprehensive performance evaluation values ​​are selected. Then, the total cost of laying and subsequent maintenance of the two sample cables is compared. If the difference between the total cost of laying and subsequent maintenance of the two sample cables is less than the preset cost difference, then the sample cable ranked first is selected as the replacement cable. Otherwise, the second-ranked sample cable is selected as the replacement cable. In this way, a more suitable replacement cable can be selected based on the comprehensive performance evaluation value. At the same time, by considering the total cost of laying and subsequent maintenance, the performance and economy can be comprehensively considered to select the optimal replacement cable scheme, thereby improving the reliability and economic benefits of the cable system.

[0122] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for selecting replacement cables, characterized in that: Includes the following steps: S1. Obtain the rated parameters of the cable to be replaced, and calculate the conductor shielding field strength and the insulation shielding field strength of the cable to be replaced based on the rated parameters of the cable to be replaced. S2. Collect environmental parameters of the construction environment and determine the limiting conditions under the current construction environment based on the collection results; S3. Based on the rated parameters of the cable to be replaced, the conductor shielding field strength of the cable to be replaced, the insulation shielding field strength of the cable to be replaced, and the limiting conditions under the current construction environment, a preliminary screening is conducted from the existing available cables to obtain a sample cable set. S4. Conduct performance tests on the sample cables and collect the physical parameters of each sample cable during each monitoring cycle in the test process. Based on the physical parameters of each sample cable during each monitoring cycle in the test process, obtain all types of performance evaluation values ​​for each sample cable in each monitoring cycle. S5. Based on the physical parameters of each sample cable in each monitoring cycle during the test and the performance evaluation values ​​of all types in each monitoring cycle, construct a comprehensive performance evaluation matrix for each sample cable in each monitoring cycle. S6. Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, calculate the comprehensive performance evaluation value of each sample cable, and select the replacement cable based on the comprehensive performance evaluation value of each sample cable. Step S4 includes: S41. Lay each sample cable in the pre-arranged simulated construction environment using the same laying method as the replacement cable, and simulate the transmission signal during the actual working process of the cable to be replaced. Connect each sample cable to the energy spectrum analyzer, moisture tester, and insulation resistance tester. The environmental parameters of the simulated construction environment are the same as those of the laying environment of the cable to be replaced. S42. Collect the percentage of copper and oxygen content of each sample cable in each monitoring cycle during the test using an energy dispersive spectroscopy analyzer; The moisture content of each sample cable joint end was collected using a moisture meter during each monitoring period of the test. The insulation resistance change of each sample cable was collected during each monitoring cycle of the test using an insulation resistance tester. S43. Input the percentage of copper and oxygen content, the moisture content of each sample cable joint end, and the change in insulation resistance of each sample cable in each monitoring cycle during the test into the trained cable oxidation resistance evaluation model, cable waterproof performance evaluation model, and cable aging performance evaluation model, respectively, to obtain the cable oxidation resistance evaluation value, cable waterproof performance evaluation value, and cable aging performance evaluation value for each sample cable in each monitoring cycle.

2. The method for selecting a replacement cable according to claim 1, characterized in that: Obtain the rated parameters of the cable to be replaced, and calculate the conductor shielding field strength and insulation shielding field strength of the cable to be replaced based on the rated parameters, including: Conductor shielding field strength of the cable to be replaced: Insulation shielding field strength of the cable to be replaced: Among them, E max E represents the conductor shielding field strength of the cable to be replaced. min U0 is the insulation shielding field strength of the cable to be replaced, U0 is the rated voltage of the cable to be replaced, D is the outer radius of the insulation of the cable to be replaced, d is the inner radius of the insulation of the cable to be replaced, and Ln is the logarithm to the base e.

3. The method for selecting a replacement cable according to claim 1, characterized in that: Collect environmental parameters of the construction environment and determine the limiting conditions under the current construction environment based on the collection results, including: S21. Collect data on the temperature, humidity, acidity / alkalinity of the cable contact environment, and external forces acting on the cable in the construction environment. S22. Based on the collected data on the construction environment temperature, humidity, cable contact environment pH, cable external force, and preset reference environment temperature, preset reference environment humidity, preset reference cable contact environment pH, and preset reference cable external force, determine the limiting conditions under the current construction environment. S23. Based on the constraints under the current construction environment, provide the upper limit value of the constraints.

4. The method for selecting a replacement cable according to claim 3, characterized in that: Step S22 includes: Compare the differences between the temperature of the construction environment and the preset reference temperature, the humidity of the construction environment and the preset reference humidity, the pH of the cable contact environment in the construction environment and the pH of the cable contact environment in the preset reference, and the environmental external force on the cable in the construction environment and the environmental external force on the cable in the preset reference. If the temperature difference between the construction environment and the preset reference environment temperature is greater than the preset temperature difference, the temperature adaptability of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the temperature adaptability range of the cable. If the difference between the construction environment humidity and the preset reference environment humidity is greater than the preset humidity difference, the waterproof performance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the range of the cable's waterproof performance. If the difference between the acidity / alkalinity of the cable contact environment during construction and the acidity / alkalinity of the preset reference cable contact environment is greater than the preset acidity / alkalinity difference, then the corrosion resistance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the range of the cable's corrosion resistance. If the difference between the environmental force exerted on the cable in the construction environment and the environmental force exerted on the preset reference cable is greater than the preset difference, then the mechanical strength performance of the cable will be used as one of the limiting conditions. In this case, the upper limit of the limiting condition is the mechanical strength range of the cable.

5. The method for selecting a replacement cable according to claim 1, characterized in that: Based on the rated parameters of the cable to be replaced, the conductor shielding field strength, the insulation shielding field strength, and the limitations of the current construction environment, a preliminary selection of available cables was made to obtain a sample cable set, including: S31. Select a cable with the same rated parameters as the cable to be replaced from the existing available cables as a preliminary screening cable; S32. Select cables from the first preliminary screening cables that have higher conductor shielding field strength and insulation shielding field strength than the cables to be replaced, and use them as second preliminary screening cables. S33. Select cables that meet the upper limit of the restriction conditions from the secondary preliminary screening cables and use them as a sample cable set.

6. The method for selecting a replacement cable according to claim 1, characterized in that: Based on the physical parameters of each sample cable during each monitoring cycle and the performance evaluation values ​​of all types for each monitoring cycle, a comprehensive performance evaluation matrix is ​​constructed for each sample cable for each monitoring cycle: in, Let a be the comprehensive performance evaluation matrix corresponding to the i-th sample cable. i1 Let a be the percentage of copper and oxygen content in the i-th sample cable during the first monitoring cycle. i2 Let a be the percentage of copper and oxygen content in the second monitoring cycle of the i-th sample cable. in Let b be the percentage of copper and oxygen content in the i-th sample cable during the n-th monitoring cycle. i1 Let b be the moisture content at the cable joint end of the i-th sample cable during the first monitoring cycle. i2 Let b be the moisture content at the cable joint end of the i-th sample cable during the second monitoring cycle. in Let c be the moisture content at the cable joint end of the i-th sample cable during the n-th monitoring cycle. i1 Let c be the change in insulation resistance of the i-th sample cable during the first monitoring cycle. i2 Let c be the change in insulation resistance of the i-th sample cable during the second monitoring cycle. in Let A be the change in insulation resistance of the i-th sample cable during the n-th monitoring period. i1 Let A be the evaluation value of the cable's oxidation resistance for the i-th sample cable in the first monitoring cycle. i2 A represents the evaluation value of the cable's oxidation resistance in the second monitoring cycle for the i-th sample cable. in B represents the evaluation value of the cable's oxidation resistance in the nth monitoring cycle for the i-th sample cable. i1 B represents the cable waterproof performance evaluation value for the i-th sample cable in the first monitoring cycle. i2 B represents the cable waterproof performance evaluation value for the i-th sample cable in the second monitoring cycle. in C represents the cable waterproof performance evaluation value for the i-th sample cable in the n-th monitoring period. i1 C represents the cable aging performance evaluation value for the i-th sample cable in the first monitoring cycle. i2 C represents the cable aging performance evaluation value for the i-th sample cable in the second monitoring cycle. in This is the cable aging performance evaluation value for the i-th sample cable in the nth monitoring cycle.

7. The method for selecting a replacement cable according to claim 1, characterized in that: Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, the comprehensive performance evaluation value of each sample cable is calculated, and replacement cables are selected based on the comprehensive performance evaluation value of each sample cable, including: S61. Based on the comprehensive performance evaluation matrix corresponding to each monitoring cycle of each sample cable, obtain the main influence value and the secondary influence value of the comprehensive performance evaluation value of each sample cable. S62. Calculate the comprehensive performance evaluation value of each sample cable based on the main influence value and the secondary influence value of the comprehensive performance evaluation value of each sample cable. S63. Compare the comprehensive performance evaluation values ​​of each sample cable, select the two sample cables with the highest comprehensive performance evaluation values, compare the total cost of laying and subsequent maintenance of the two sample cables, and if the difference between the total cost of laying and subsequent maintenance of the two sample cables is less than the preset cost difference, then select the sample cable with the highest ranking as the replacement cable. Otherwise, select the second-ranked sample cable as the replacement cable.

8. A method for selecting a replacement cable according to claim 7, characterized in that: Step S61 includes: In the comprehensive performance evaluation matrix elements corresponding to each monitoring cycle of each sample cable, the performance evaluation values ​​of each type and their corresponding monitoring data are deleted to obtain the evaluation matrix of each type of performance. If the rank of the evaluation matrix for each type of performance of the sample cable is greater than the preset threshold of the corresponding type performance evaluation value, then the performance evaluation value of the corresponding type in the last cycle of the sample cable is taken as the main influencing value of the comprehensive performance evaluation value; otherwise, it is taken as the secondary influencing value of the comprehensive performance evaluation value.

9. The method for selecting a replacement cable according to claim 1, characterized in that: The overall performance evaluation value for each sample cable is calculated based on the primary influence value and the secondary influence value of the overall performance evaluation value: in, Let be the comprehensive performance evaluation value of the i-th sample cable, u be the total number of main influencing values ​​of the comprehensive performance evaluation value of the i-th sample cable, and χ be the total number of influencing values. j Let Y be the j-th major influencing value of the comprehensive performance evaluation of the i-th sample cable, where e is a natural number with a value of 2.

71. k This is the secondary influence value of the kth comprehensive performance evaluation value of the i-th sample cable.

Images