A method, system, device and medium for evaluating the aging degree of cable sheath

Abstract

The present invention discloses a method, system, device and medium for evaluating the degree of aging of a cable sheath. The present invention includes obtaining cable sheath information corresponding to a cable sheath aging evaluation request in response to a received cable sheath aging evaluation request; obtaining the insulation resistance value, dielectric loss tangent value and tensile strength value of the cable sheath based on the cable sheath information; determining the electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath; determining the mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath; and determining the degree of aging of the cable sheath based on the electrical aging factor and mechanical aging factor of the cable sheath. The present invention solves the technical problem that existing detection means cannot evaluate the degree of aging of 110kV cable sheaths. The present invention is simple and efficient, and can correctly evaluate the degree of aging of 110kV cable sheaths that have been laid underground and operated for a long time.

Description

Technical Field

[0001] The present invention relates to the technical field of cable sheath aging assessment, and in particular to a cable sheath aging degree assessment method, system, equipment and medium. Background Art

[0002] In the power industry, to ensure reliable and stable power supply, while also considering factors such as construction and maintenance cost-effectiveness, space utilization, and environmental protection, power cables have become the preferred choice for line construction, gradually forming a vast urban distribution network system. Some high-voltage cables are installed underground, facing complex operating conditions. During operation, they may age due to external damage, overload, heat and humidity, chemical corrosion, and other factors, affecting normal operation. The cable sheath is the outermost layer of the cable and is directly exposed to the complex external environment. If the cable sheath continues to age, it will continue to affect the insulation performance and complicate cable maintenance and repair. Therefore, accurately assessing the degree of cable sheath aging is crucial to ensuring the safe operation of the power system.

[0003] 110kV cables are commonly used in distribution networks. As 110kV cables are primarily laid underground, their sheaths are inevitably subject to complex environmental conditions, leading to aging. Therefore, 110kV cable sheaths are an important target for aging testing. However, existing testing methods primarily focus on detecting aging of the cable insulation layer. There is a lack of effective methods for assessing the sheath aging of 110kV cables operating in distribution networks over the long term, making it difficult to assess the extent of 110kV cable sheath aging. Summary of the Invention

[0004] The present invention provides a method, system, device and medium for evaluating the degree of aging of cable sheaths, which solves the technical problem that the existing detection means mostly detect the aging of cable insulation layers, lack of an effective method for evaluating the aging of 110kV cable sheaths in long-term operation in distribution networks, and the inability to evaluate the degree of aging of 110kV cable sheaths.

[0005] A first aspect of the present invention provides a method for evaluating the aging degree of a cable sheath, comprising:

[0006] In response to the received cable sheath aging degree assessment request, obtaining cable sheath information corresponding to the cable sheath aging degree assessment request;

[0007] Based on the cable sheath information, obtaining the insulation resistance value, dielectric loss tangent value and tensile strength value of the cable sheath;

[0008] Determining an electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath;

[0009] Determining a mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath;

[0010] The aging degree of the cable sheath is determined based on the electrical aging factor and the mechanical aging factor of the cable sheath.

[0011] Optionally, before the step of obtaining the insulation resistance, dielectric loss tangent and tensile strength of the cable sheath based on the cable sheath information, the method further includes:

[0012] Cutting a first cable sample to be tested to a first preset length;

[0013] Measuring the first cable sample to be tested using a preset measurement voltage to generate a plurality of insulation resistance values;

[0014] cutting a second cable sample to be tested into a second preset length;

[0015] Measuring both ends of the second cable sample to be tested to obtain multiple sets of dielectric loss angle values ​​and dielectric constants;

[0016] Calculating a dielectric loss tangent value of the second cable sample to be tested using the dielectric loss angle value and the dielectric constant;

[0017] cutting the outer layer of the third cable to be tested into a third preset length;

[0018] Perform a mechanical tensile test on the outer layer of the third cable to be tested to generate a plurality of tensile strength values.

[0019] Optionally, the step of determining the electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath comprises:

[0020] Calculating a weighted average value of the insulation resistance of the cable sheath by using the insulation resistance value of the cable sheath and a first preset value;

[0021] Calculating a weighted average value of the dielectric loss tangent of the cable sheath by using the dielectric loss tangent value of the cable sheath and a second preset value;

[0022] Calculating a maximum dielectric loss tangent value and a minimum dielectric loss tangent value of the cable sheath by using a plurality of dielectric loss tangent values ​​of the cable sheath;

[0023] The electrical aging factor of the cable sheath is calculated using the insulation resistance value, the weighted average value of the insulation resistance, the weighted average value of the dielectric loss tangent, the maximum value of the dielectric loss tangent, and the minimum value of the dielectric loss tangent of the cable sheath; wherein the calculation formula of the electrical aging factor is:

[0024]

[0025] Where α is the electrical aging factor, is the weighted average value of dielectric loss tangent, δ max and δ min The maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, R i is the insulation resistance value, is the weighted average value of insulation resistance.

[0026] Optionally, the step of determining the mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath comprises:

[0027] Calculating a weighted average value of the tensile strength of the cable sheath using the tensile strength value of the cable sheath and a third preset value;

[0028] The mechanical aging factor of the cable sheath is calculated using the tensile strength value and the weighted average value of the tensile strength of the cable sheath; wherein the calculation formula of the mechanical aging factor is:

[0029]

[0030] Where β is the mechanical aging factor, RM ij is the tensile strength value, is the weighted average of tensile strength.

[0031] Optionally, the step of determining the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath comprises:

[0032] Calculating the product of the electrical aging factor and the mechanical aging factor of the cable sheath to generate the electrical joint parameter of the cable sheath;

[0033] Determining whether a power joint parameter of the cable sheath is greater than or equal to a first preset parameter threshold;

[0034] If yes, it is determined that the cable sheath is slightly aged;

[0035] If not, determining whether the power joint parameter of the cable sheath is less than the first preset parameter threshold and greater than or equal to the second preset parameter threshold;

[0036] If yes, the cable sheath is determined to be moderately aged;

[0037] If not, determining whether the power joint parameter of the cable sheath is less than the second preset parameter threshold and greater than or equal to the third preset parameter threshold;

[0038] If so, it is determined that the cable sheath is severely aged.

[0039] A second aspect of the present invention provides a cable sheath aging degree assessment system, comprising:

[0040] a cable sheath information module, configured to, in response to a received cable sheath aging degree assessment request, obtain cable sheath information corresponding to the cable sheath aging degree assessment request;

[0041] An acquisition module, configured to acquire an insulation resistance value, a dielectric loss tangent value, and a tensile strength value of the cable sheath based on the cable sheath information;

[0042] An electrical aging factor module, configured to determine an electrical aging factor of the cable sheath based on an insulation resistance value and a dielectric loss tangent value of the cable sheath;

[0043] A mechanical aging factor module, configured to determine a mechanical aging factor of the cable sheath based on a tensile strength value of the cable sheath;

[0044] The aging degree module is used to determine the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath.

[0045] Optionally, before the acquisition module, the method further includes:

[0046] A first cable sample submodule to be tested, used for cutting a first cable sample to be tested to a first preset length;

[0047] an insulation resistance value submodule, configured to measure the first cable sample to be tested using a preset measurement voltage to generate a plurality of insulation resistance values;

[0048] A second cable sample submodule to be tested, used for cutting a second cable sample to be tested to a second preset length;

[0049] A dielectric constant submodule, configured to measure both ends of the second cable sample to be tested to obtain multiple sets of dielectric loss angle values ​​and dielectric constants;

[0050] a dielectric loss tangent value submodule, configured to calculate the dielectric loss tangent value of the second cable sample to be tested by using the dielectric loss tangent value and the dielectric constant;

[0051] A third test cable outer layer submodule, used for cutting the outer layer of the third test cable into a third preset length;

[0052] The tensile strength value submodule is used to perform a mechanical tensile test on the outer layer of the third cable to be tested to generate a plurality of tensile strength values.

[0053] Optionally, the electrical aging factor module includes:

[0054] an insulation resistance weighted average value submodule, configured to calculate a weighted average value of the insulation resistance of the cable sheath by using the insulation resistance value of the cable sheath and a first preset value;

[0055] a dielectric loss tangent weighted average submodule, configured to calculate a dielectric loss tangent weighted average of the cable sheath using the dielectric loss tangent value of the cable sheath and a second preset value;

[0056] A dielectric loss tangent minimum value submodule is used to calculate a maximum dielectric loss tangent value and a minimum dielectric loss tangent value of the cable sheath using multiple dielectric loss tangent values ​​of the cable sheath;

[0057] The electrical aging factor submodule is used to calculate the electrical aging factor of the cable sheath using the insulation resistance value, the weighted average value of the insulation resistance, the weighted average value of the dielectric loss tangent, the maximum dielectric loss tangent, and the minimum dielectric loss tangent of the cable sheath; wherein the calculation formula of the electrical aging factor is:

[0058]

[0059] Where α is the electrical aging factor, is the weighted average value of dielectric loss tangent, δ max and δ min The maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, R i is the insulation resistance value, is the weighted average value of insulation resistance.

[0060] A third aspect of the present invention provides an electronic device comprising a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the cable sheath aging degree assessment method as described in any one of the above items.

[0061] A fourth aspect of the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed, implements the cable sheath aging degree assessment method as described in any one of the above items.

[0062] It can be seen from the above technical solutions that the present invention has the following advantages:

[0063] The present invention measures the electrical parameters insulation resistance, dielectric loss factor and mechanical parameter tensile strength of the cable sheath respectively, and calculates the power joint parameters to evaluate the aging degree of the 110kV cable sheath. This method is simple and efficient, and can accurately evaluate the aging degree of the 110kV cable sheath that has been laid underground and operated for a long time. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0065] Figure 1 A flowchart of a method for evaluating the aging degree of a cable sheath provided in Example 1 of the present invention;

[0066] Figure 2 A flowchart of a method for evaluating the aging degree of a cable sheath provided in the second embodiment of the present invention;

[0067] Figure 3 This is a structural block diagram of a cable sheath aging degree assessment system provided in Example 3 of the present invention. DETAILED DESCRIPTION

[0068] The embodiments of the present invention provide a method, system, device and medium for evaluating the degree of aging of cable sheaths, which are used to solve the technical problem that the existing detection means mostly detect the aging of cable insulation layers, lack an effective method for evaluating the aging of 110kV cable sheaths in long-term operation in distribution networks, and are unable to evaluate the degree of aging of 110kV cable sheaths.

[0069] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0070] See also Figure 1 , Figure 1 This is a flowchart of the steps of a method for evaluating the aging degree of a cable sheath provided in Example 1 of the present invention.

[0071] The present invention provides a method for evaluating the aging degree of a cable sheath, comprising the following steps:

[0072] Step 101: In response to a received cable sheath aging degree assessment request, obtain cable sheath information corresponding to the cable sheath aging degree assessment request.

[0073] It should be noted that the request for cable sheath aging assessment refers to a request for assessing the aging degree of the cable sheath.

[0074] Cable sheath information refers to data such as the insulation resistance value, dielectric loss tangent value and tensile strength value of the cable sheath.

[0075] In specific implementation, when a cable sheath aging degree assessment request is received, cable information of the cable corresponding to the request is obtained, such as the insulation resistance value, dielectric loss tangent value, and tensile strength value of the cable sheath.

[0076] Step 102: Based on the cable sheath information, obtain the insulation resistance value, dielectric loss tangent value, and tensile strength value of the cable sheath.

[0077] It should be noted that the insulation resistance value and dielectric loss tangent value of the cable sheath's electrical parameters, as well as the tensile strength value of the mechanical parameters, are extracted from the cable sheath information to calculate the electric-mechanical joint parameters of the cable sheath, which is convenient for evaluating the aging degree of the 110kV cable sheath.

[0078] Step 103: Determine the electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath.

[0079] It should be noted that the insulation resistance value of the cable sheath can be used to calculate the weighted average value of the insulation resistance. Similarly, the weighted average value of the dielectric loss tangent, the maximum dielectric loss tangent, and the minimum dielectric loss tangent can be calculated by using multiple dielectric loss tangent values.

[0080] In specific implementation, the electrical aging factor of the cable sheath can be calculated by using the insulation resistance value, weighted average value of insulation resistance, weighted average value of dielectric loss tangent, maximum value of dielectric loss tangent, and minimum value of dielectric loss tangent of the cable sheath.

[0081] Step 104: Determine the mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath.

[0082] It should be noted that the tensile strength value of the cable sheath can be used to calculate the weighted average value of the tensile strength, and the mechanical aging factor of the cable sheath can be calculated by using the tensile strength value and the weighted average value of the tensile strength.

[0083] Step 105: Determine the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath.

[0084] It should be noted that by multiplying the electrical aging factor and the mechanical aging factor of the cable sheath, the electric-mechanical joint parameter of the cable sheath can be obtained. By comparing the parameter range of the electric-mechanical joint parameter of the cable sheath, the aging degree of the cable sheath can be known.

[0085] See also Figure 2 , Figure 2 This is a flowchart of the steps of a method for evaluating the aging degree of a cable sheath provided in Example 2 of the present invention.

[0086] The present invention provides a method for evaluating the aging degree of a cable sheath, comprising the following steps:

[0087] Step 201: In response to a received cable sheath aging degree assessment request, obtain cable sheath information corresponding to the cable sheath aging degree assessment request.

[0088] In the embodiment of the present invention, the specific implementation of step 201 is similar to that of step 101 and will not be repeated here.

[0089] Step 202: Cut a first cable sample to be tested into a first preset length.

[0090] It should be noted that the first preset length is 1m.

[0091] During the specific implementation, a 1-meter cable sample section to be tested (i.e., the first cable sample to be tested) is cut out with an electric saw, and the cable insulation layer and the internal copper conductor are stripped off using tools, leaving the metal shielding layer and the red outer sheath. The surface of the outer sheath is evenly covered with aluminum foil or copper foil tape to facilitate the measurement of the insulation resistance of the sheath.

[0092] Step 203: Measure the first cable sample to be tested using a preset measurement voltage to generate a plurality of insulation resistance values.

[0093] It should be noted that the preset measurement voltage is 2kV and the measurement time is 30 seconds. If the display is unstable, the measurement time can be appropriately increased. To ensure sufficient measurement of the cable sheath, 6 groups of insulation resistance values ​​are repeatedly measured at different corresponding positions at both ends of the cable sample to be tested, namely R1, R2, R3, R4, R5 and R6, in GΩ.

[0094] Step 204: Cut a second cable sample to be tested into a second preset length.

[0095] It should be noted that the second preset length is 0.25m.

[0096] During specific implementation, the cable sheath is further cut into a 0.25 m long cable sample section to be tested (ie, the second cable sample to be tested).

[0097] Step 205: Measure both ends of the second cable sample to obtain multiple sets of dielectric loss angle values ​​and dielectric constants.

[0098] It should be noted that circular samples were cut from both ends of each 0.25m cable sample section to be tested, and a total of two sets of dielectric loss angle values ​​were obtained for each section. A circular sample with a thickness of 3mm and a radius of 1cm was cut from the outer sheath of each section using a punching machine, and the dielectric constant of the cable sample section to be tested was measured using a broadband dielectric spectrometer.

[0099] Step 206: Calculate the dielectric loss tangent value of the second cable sample to be tested using the dielectric loss angle value and the dielectric constant.

[0100] It should be noted that the dielectric loss angle value and dielectric constant are applied, and the dielectric loss tangent value is further calculated. The test voltage when the dielectric constant of the cable sample to be tested is measured using a broadband dielectric spectrometer is 2.5kV, the test frequency is 1kHz, and the test result is recorded as δ i1 , δ i2 (i=1,2,3,4).

[0101] Step 207: Cut the outer layer of the third cable to be tested into a third preset length.

[0102] It should be noted that the third preset length is 0.25m.

[0103] In specific implementation, a punching machine is used to cut out each 0.25 m cable outer sheath into dumbbell-shaped test cable outer layer samples (ie, the third test cable outer layer) with a length of 15 cm and a thickness of 5 mm.

[0104] Step 208: Perform a mechanical tensile test on the outer layer of the third cable to be tested to generate a plurality of tensile strength values.

[0105] It should be noted that the dumbbell-shaped outer layer sample of the cable to be tested is fixed on the fixture and the mechanical tensile test is performed using a material tensile testing machine. In order to ensure sufficient measurement of the cable sheath, 4 dumbbell-shaped outer layer samples of the cable to be tested are cut from each 0.25m cable. The test results are recorded as RM i1 , RM i2 , RM i3 , RM i4 (i=1,2,3,4).

[0106] Step 209: Based on the cable sheath information, obtain the insulation resistance value, dielectric loss tangent value, and tensile strength value of the cable sheath.

[0107] It should be noted that the insulation resistance value, dielectric loss tangent value and tensile strength value of the cable sheath are extracted from the cable sheath information.

[0108] Step 210: Determine the electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath.

[0109] Optionally, step 210 includes the following steps S11-S14:

[0110] S11, calculating a weighted average value of the insulation resistance of the cable sheath using the insulation resistance value of the cable sheath and a first preset value;

[0111] S12, calculating a weighted average value of the dielectric loss tangent of the cable sheath using the dielectric loss tangent value of the cable sheath and a second preset value;

[0112] S13, using multiple dielectric loss tangent values ​​of the cable sheath, calculating the maximum dielectric loss tangent and the minimum dielectric loss tangent of the cable sheath;

[0113] S14. Calculate the electrical aging factor of the cable sheath using the insulation resistance value, the weighted average value of the insulation resistance, the weighted average value of the dielectric loss tangent, the maximum value of the dielectric loss tangent, and the minimum value of the dielectric loss tangent of the cable sheath; the calculation formula for the electrical aging factor is:

[0114]

[0115] Where α is the electrical aging factor, is the weighted average value of dielectric loss tangent, δ max and δ min The maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, R i is the insulation resistance value, is the weighted average value of insulation resistance.

[0116] It should be noted that the first preset value and the second preset value are 1 / 6 and 1 / 8 respectively.

[0117] In specific implementation, the calculation formula for the weighted average value of the insulation resistance of the cable sheath is:

[0118]

[0119] Where, is the weighted average value of insulation resistance, R i is the insulation resistance value, and 1 / 6 is the first preset value.

[0120] The calculation formula for the weighted average value of dielectric loss tangent is:

[0121]

[0122] Where, is the weighted average value of dielectric loss tangent, δ ij is the dielectric loss tangent value, and 1 / 8 is the second preset value.

[0123] The calculation formula of electrical aging factor is:

[0124]

[0125] Where α is the electrical aging factor, is the weighted average value of dielectric loss tangent, δ max and δ min The maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, R i is the insulation resistance value, is the weighted average value of insulation resistance.

[0126] Step 211: Determine the mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath.

[0127] Optionally, step 211 includes the following steps S21-S22:

[0128] S21. Calculate a weighted average tensile strength of the cable sheath using the tensile strength value of the cable sheath and a third preset value;

[0129] S22. Calculate the mechanical aging factor of the cable sheath using the tensile strength value and the weighted average value of the tensile strength of the cable sheath; wherein the calculation formula of the mechanical aging factor is:

[0130]

[0131] Where β is the mechanical aging factor, RM ij is the tensile strength value, is the weighted average of tensile strength.

[0132] It should be noted that the third preset value is 1 / 4.

[0133] The calculation formula for the weighted average tensile strength of the cable sheath is:

[0134]

[0135] Where, is the weighted average value of tensile strength, RM ij is the tensile strength value, and 1 / 4 is the third preset value.

[0136] The calculation formula of mechanical aging factor is:

[0137]

[0138] Where β is the mechanical aging factor, RM ij is the tensile strength value, is the weighted average of tensile strength.

[0139] Step 212: Determine the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath.

[0140] Optionally, step 212 includes the following steps S31-S37:

[0141] S31. Calculate the product of the electrical aging factor and the mechanical aging factor of the cable sheath to generate the power joint parameter of the cable sheath;

[0142] S32, determining whether the power joint parameter of the cable sheath is greater than or equal to a first preset parameter threshold;

[0143] S33. If yes, the cable sheath is judged to be slightly aged;

[0144] S34. If not, determine whether the power joint parameter of the cable sheath is less than the first preset parameter threshold and greater than or equal to the second preset parameter threshold;

[0145] S35. If yes, the cable sheath is judged to be moderately aged;

[0146] S36. If not, determine whether the power combined parameter of the cable sheath is less than the second preset parameter threshold and greater than or equal to the third preset parameter threshold;

[0147] S37. If yes, the cable sheath is judged to be severely aged.

[0148] It should be noted that the first preset parameter threshold is 6.6, the second preset parameter threshold is 2.19, and the third preset parameter threshold is 0.

[0149] In specific implementation, the calculation formula of the electric-power combined parameter (i.e., electric power combined parameter) of the cable sheath is:

[0150] γ=α·β

[0151] Where γ is the electrical-mechanical joint parameter, α is the electrical aging factor, and β is the mechanical aging factor.

[0152] Specifically, if γ ≥ 6.6, the sheath of the cable under test is slightly aged;

[0153] If 2.19≤γ<6.6, the sheath of the cable to be tested is moderately aged;

[0154] If 0≤γ<2.19, the sheath of the cable to be tested is severely aged.

[0155] See also Figure 3, Figure 3 This is a structural block diagram of a cable sheath aging degree assessment system provided in Example 3 of the present invention.

[0156] The present invention provides a cable sheath aging degree assessment system, comprising:

[0157] The cable sheath information module 301 is configured to obtain the cable sheath information corresponding to the cable sheath aging degree assessment request in response to the received cable sheath aging degree assessment request;

[0158] An acquisition module 302 is configured to acquire the insulation resistance value, dielectric loss tangent value, and tensile strength value of the cable sheath based on the cable sheath information;

[0159] The electrical aging factor module 303 is used to determine the electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath;

[0160] A mechanical aging factor module 304 is used to determine a mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath;

[0161] The aging degree module 305 is used to determine the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath.

[0162] Optionally, before obtaining module 302, the system further includes:

[0163] A first cable sample submodule to be tested, used for cutting a first cable sample to be tested to a first preset length;

[0164] The insulation resistance value submodule is used to measure the first cable sample to be tested using a preset measurement voltage to generate multiple insulation resistance values;

[0165] A second cable sample submodule to be tested, used for cutting a second cable sample to be tested to a second preset length;

[0166] The dielectric constant submodule is used to measure both ends of the second cable sample to obtain multiple sets of dielectric loss angle values ​​and dielectric constants;

[0167] a dielectric loss tangent value submodule, configured to calculate a dielectric loss tangent value of a second cable sample to be tested using the dielectric loss tangent value and the dielectric constant;

[0168] A third test cable outer layer submodule, used for cutting the outer layer of the third test cable into a third preset length;

[0169] The tensile strength value submodule is used to perform a mechanical tensile test on the outer layer of the third cable to be tested and generate multiple tensile strength values.

[0170] Optionally, the electrical aging factor module includes:

[0171] The insulation resistance weighted average value submodule is used to calculate the insulation resistance weighted average value of the cable sheath using the insulation resistance value of the cable sheath and a first preset value;

[0172] A dielectric loss tangent weighted average submodule, configured to calculate a dielectric loss tangent weighted average of the cable sheath using the dielectric loss tangent value of the cable sheath and a second preset value;

[0173] The dielectric loss tangent minimum submodule is used to calculate the maximum and minimum dielectric loss tangents of the cable sheath using multiple dielectric loss tangent values ​​of the cable sheath;

[0174] The electrical aging factor submodule is used to calculate the electrical aging factor of the cable sheath using the insulation resistance value, the weighted average value of the insulation resistance, the weighted average value of the dielectric loss tangent, the maximum dielectric loss tangent, and the minimum dielectric loss tangent of the cable sheath. The calculation formula of the electrical aging factor is:

[0175]

[0176] Where α is the electrical aging factor, is the weighted average value of dielectric loss tangent, δ max and δ min The maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, R i is the insulation resistance value, is the weighted average value of insulation resistance.

[0177] Optionally, the mechanical aging factor module 304 includes:

[0178] A tensile strength weighted average submodule, configured to calculate a weighted average tensile strength of the cable sheath using the tensile strength value of the cable sheath and a third preset value;

[0179] The mechanical aging factor submodule is used to calculate the mechanical aging factor of the cable sheath using the tensile strength value and the weighted average value of the tensile strength of the cable sheath. The calculation formula of the mechanical aging factor is:

[0180]

[0181] Where β is the mechanical aging factor, RM ij is the tensile strength value, is the weighted average of tensile strength.

[0182] Optionally, the aging degree module 305 includes:

[0183] The power joint parameter submodule is used to calculate the product of the electrical aging factor and the mechanical aging factor of the cable sheath to generate the power joint parameters of the cable sheath;

[0184] A first judgment submodule is used to judge whether the power joint parameter of the cable sheath is greater than or equal to a first preset parameter threshold;

[0185] The light aging submodule is used to determine that the cable sheath is lightly aged if yes;

[0186] a second judgment submodule, for judging, if not, whether the power joint parameter of the cable sheath is less than a first preset parameter threshold and greater than or equal to a second preset parameter threshold;

[0187] The medium aging submodule is used to determine that the cable sheath is medium aged if yes;

[0188] a third judgment submodule, for judging, if not, whether the power joint parameter of the cable sheath is less than the second preset parameter threshold and greater than or equal to the third preset parameter threshold;

[0189] The severe aging submodule is used to determine that the cable sheath is severely aged if yes.

[0190] A fourth embodiment of the present invention provides an electronic device comprising a memory and a processor. The memory stores a computer program. When the computer program is executed by the processor, the processor executes the steps of the cable sheath aging degree assessment method as described in any of the above embodiments.

[0191] A fifth embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed, the method for evaluating the aging degree of a cable sheath as described in any of the above embodiments is implemented.

[0192] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0193] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0194] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0195] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0196] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it 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 all or 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 and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0197] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments can still be modified, or some of the technical features thereof can be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for evaluating the aging degree of a cable sheath, characterized in that: include: In response to the received cable sheath aging degree assessment request, obtaining cable sheath information corresponding to the cable sheath aging degree assessment request; Based on the cable sheath information, obtaining the insulation resistance value, dielectric loss tangent value and tensile strength value of the cable sheath; Determining an electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath; Determining a mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath; Determining the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath; The step of determining the electrical aging factor of the cable sheath based on the insulation resistance value and dielectric loss tangent value of the cable sheath comprises: Calculating a weighted average value of the insulation resistance of the cable sheath by using the insulation resistance value of the cable sheath and a first preset value; Calculating a weighted average value of the dielectric loss tangent of the cable sheath by using the dielectric loss tangent value of the cable sheath and a second preset value; Calculating a maximum dielectric loss tangent value and a minimum dielectric loss tangent value of the cable sheath by using a plurality of dielectric loss tangent values ​​of the cable sheath; The electrical aging factor of the cable sheath is calculated using the insulation resistance value, the weighted average value of the insulation resistance, the weighted average value of the dielectric loss tangent, the maximum value of the dielectric loss tangent, and the minimum value of the dielectric loss tangent of the cable sheath; wherein the calculation formula of the electrical aging factor is: ； Where, is the electrical aging factor, is the weighted average value of dielectric loss tangent, and They are the maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, is the insulation resistance value, is the weighted average value of insulation resistance; The step of determining the mechanical aging factor of the cable sheath based on the tensile strength value of the cable sheath comprises: Calculating a weighted average value of the tensile strength of the cable sheath using the tensile strength value of the cable sheath and a third preset value; The mechanical aging factor of the cable sheath is calculated using the tensile strength value and the weighted average value of the tensile strength of the cable sheath; wherein the calculation formula of the mechanical aging factor is: ； Where, is the mechanical aging factor, is the tensile strength value, is the weighted average of tensile strength.

2. The method for evaluating the aging degree of a cable sheath according to claim 1, wherein: Before the step of obtaining the insulation resistance, dielectric loss tangent value and tensile strength of the cable sheath based on the cable sheath information, the method further includes: Cutting a first cable sample to be tested to a first preset length; Measuring the first cable sample to be tested using a preset measurement voltage to generate a plurality of insulation resistance values; cutting a second cable sample to be tested into a second preset length; Measuring both ends of the second cable sample to be tested to obtain multiple sets of dielectric loss angle values ​​and dielectric constants; Calculating a dielectric loss tangent value of the second cable sample to be tested using the dielectric loss angle value and the dielectric constant; cutting the outer layer of the third cable to be tested into a third preset length; Perform a mechanical tensile test on the outer layer of the third cable to be tested to generate a plurality of tensile strength values.

3. The method for evaluating the aging degree of a cable sheath according to claim 1, wherein: The step of determining the aging degree of the cable sheath based on the electrical aging factor and the mechanical aging factor of the cable sheath comprises: Calculating the product of the electrical aging factor and the mechanical aging factor of the cable sheath to generate the electrical joint parameter of the cable sheath; Determining whether a power joint parameter of the cable sheath is greater than or equal to a first preset parameter threshold; If yes, it is determined that the cable sheath is slightly aged; If not, determining whether the power joint parameter of the cable sheath is less than the first preset parameter threshold and greater than or equal to the second preset parameter threshold; If yes, the cable sheath is determined to be moderately aged; If not, determining whether the power joint parameter of the cable sheath is less than the second preset parameter threshold and greater than or equal to the third preset parameter threshold; If so, it is determined that the cable sheath is severely aged.

4. A cable sheath aging degree assessment system, characterized in that: include: a cable sheath information module, configured to, in response to a received cable sheath aging degree assessment request, obtain cable sheath information corresponding to the cable sheath aging degree assessment request; An acquisition module, configured to acquire an insulation resistance value, a dielectric loss tangent value, and a tensile strength value of the cable sheath based on the cable sheath information; An electrical aging factor module, configured to determine an electrical aging factor of the cable sheath based on an insulation resistance value and a dielectric loss tangent value of the cable sheath; A mechanical aging factor module, configured to determine a mechanical aging factor of the cable sheath based on a tensile strength value of the cable sheath; An aging degree module, configured to determine an aging degree of the cable sheath based on an electrical aging factor and a mechanical aging factor of the cable sheath; The electrical aging factor module includes: an insulation resistance weighted average value submodule, configured to calculate a weighted average value of the insulation resistance of the cable sheath by using the insulation resistance value of the cable sheath and a first preset value; a dielectric loss tangent weighted average submodule, configured to calculate a dielectric loss tangent weighted average of the cable sheath using the dielectric loss tangent value of the cable sheath and a second preset value; A dielectric loss tangent minimum value submodule is configured to calculate a maximum dielectric loss tangent value and a minimum dielectric loss tangent value of the cable sheath using a plurality of dielectric loss tangent values ​​of the cable sheath; The electrical aging factor submodule is used to calculate the electrical aging factor of the cable sheath using the insulation resistance value, the weighted average value of the insulation resistance, the weighted average value of the dielectric loss tangent, the maximum dielectric loss tangent, and the minimum dielectric loss tangent of the cable sheath; wherein the calculation formula of the electrical aging factor is: ； Where, is the electrical aging factor, is the weighted average value of dielectric loss tangent, and They are the maximum and minimum values ​​of the dielectric loss tangent of 8 groups of dielectric loss tangent values, is the insulation resistance value, is the weighted average value of insulation resistance; The mechanical aging factor module includes: a tensile strength weighted average submodule, configured to calculate a weighted average tensile strength of the cable sheath using the tensile strength value of the cable sheath and a third preset value; The mechanical aging factor submodule is used to calculate the mechanical aging factor of the cable sheath using the tensile strength value and the weighted average value of the tensile strength of the cable sheath; wherein the calculation formula of the mechanical aging factor is: ； Where, is the mechanical aging factor, is the tensile strength value, is the weighted average of tensile strength.

5. The cable sheath aging degree assessment system according to claim 4, characterized in that: Before the acquisition module, it also includes: A first cable sample submodule to be tested, used for cutting a first cable sample to be tested to a first preset length; an insulation resistance value submodule, configured to measure the first cable sample to be tested using a preset measurement voltage to generate a plurality of insulation resistance values; A second cable sample submodule to be tested, used for cutting a second cable sample to be tested to a second preset length; A dielectric constant submodule, configured to measure both ends of the second cable sample to be tested to obtain multiple sets of dielectric loss angle values ​​and dielectric constants; a dielectric loss tangent value submodule, configured to calculate the dielectric loss tangent value of the second cable sample to be tested by using the dielectric loss tangent value and the dielectric constant; A third test cable outer layer submodule, used for cutting the outer layer of the third test cable into a third preset length; The tensile strength value submodule is used to perform a mechanical tensile test on the outer layer of the third cable to be tested to generate a plurality of tensile strength values.

6. An electronic device, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the processor executes the steps of the cable sheath aging degree assessment method according to any one of claims 1 to 3.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed, the method for evaluating the aging degree of the cable sheath according to any one of claims 1 to 3 is implemented.

Images