WO2023173662A1 - 一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质 - Google Patents

一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质 Download PDF

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Publication number
WO2023173662A1
WO2023173662A1 PCT/CN2022/111004 CN2022111004W WO2023173662A1 WO 2023173662 A1 WO2023173662 A1 WO 2023173662A1 CN 2022111004 W CN2022111004 W CN 2022111004W WO 2023173662 A1 WO2023173662 A1 WO 2023173662A1
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Prior art keywords
buffer layer
cable
volume
electrode
deformed
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PCT/CN2022/111004
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English (en)
French (fr)
Inventor
房晟辰
于洋
李维博
宋鹏先
贺春
张弛
唐庆华
李隆基
张春晖
李松原
路菲
李琳
杨磊
王晓光
朱旭亮
段明辉
王浩鸣
范巍
Original Assignee
国网天津市电力公司电力科学研究院
国网天津市电力公司
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Application filed by 国网天津市电力公司电力科学研究院, 国网天津市电力公司 filed Critical 国网天津市电力公司电力科学研究院
Priority to US17/928,288 priority Critical patent/US20240241168A1/en
Publication of WO2023173662A1 publication Critical patent/WO2023173662A1/zh

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
    • G01R31/14—Circuits therefor, e.g. for generating test voltages, sensing circuits
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
    • G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
    • G01R31/1245—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of line insulators or spacers, e.g. ceramic overhead line cap insulators; of insulators in HV bushings

Definitions

  • the present invention relates to the field of cable technology, and in particular to a method, device, equipment and storage medium for defect detection of a cable buffer layer.
  • the buffer layer of the cable not only assumes the function of mechanical force buffering, but more importantly, realizes the electrical connection between the cable insulation shield and the grounded metal sheath.
  • the ablation hazards of the buffer layer mainly include partial discharge ablation, current-induced thermal ablation, and electrochemical ablation. These hazards are caused by the serious increase in volume resistivity of the buffer layer after it becomes damp. The volume resistivity increases. As a result, the insulation shield and the metal sheath cannot form a good electrical connection, causing failure. Therefore, calculating the volume resistivity of the buffer layer can directly reflect whether there are quality defects in the cable.
  • the current volume resistivity detection method is only applicable to the finished buffer layer that has not been wrapped on the cable, not the buffer layer wrapping tape taken out of the finished cable. In the power cable production process, there are still wrinkles after the buffer layer is wrapped. There are many processes such as metal sleeve production and air tightness testing, which will lead to a decrease in the quality of the buffer layer due to moisture in the subsequent production process, which cannot be found in the finished buffer layer inspection stage. Exposing the finished buffer layer to be tested to the air is very different from the relatively closed environment inside the cable, so the test results cannot accurately reflect the true condition of the buffer layer wrapping tape in the cable. In addition, the current volume resistivity detection method is only suitable for the detection of a single layer of buffer layer.
  • the buffer layer wrapping tape is generally in the form of multiple layers covering each other.
  • the outer layer is relatively exposed to the air and is more likely to get damp.
  • the inner layer is less likely to get damp.
  • the detection conclusions of the inner and outer layers of the buffer wrapping tape are inconsistent from time to time, resulting in the detection results not accurately reflecting the true condition of the buffer layer wrapping tape in the cable.
  • the current volume resistivity detection method is still rudimentary in considering the impact of the pressure on the buffer layer's volume resistivity, and cannot accurately calculate the volume resistivity, resulting in the inability to accurately determine whether there are quality defects in the cable buffer layer.
  • the technical problem to be solved by the embodiments of the present invention is to provide a method, device, equipment and storage medium for defect detection of a cable buffer layer, which can accurately calculate the volume resistivity of the cable buffer layer, and thereby accurately judge the cable based on the volume resistivity. Whether there are quality defects in the buffer layer.
  • an embodiment of the present invention provides a method for detecting defects in a cable buffer layer, which includes:
  • the specification parameters include the inner radius of the corrugated sheath, the first outer radius of the cable under test including the buffer layer, and the first outer radius of the cable under test including the shielding layer.
  • the buffer layer According to the first outer radius of the cable under test including the buffer layer, the second outer radius of the cable under test including the shielding layer, and the wrinkle pitch, it is calculated that the buffer layer has not deformed.
  • the first outer radius of the cable under test including the buffer layer
  • the second outer radius of the cable under test including the shielding layer and the maximum radius of the buffer layer.
  • Thin point thickness calculate the second volume of the deformed part when the buffer layer is deformed under force
  • the compressive deformation ratio of the buffer layer is calculated based on the first volume and the second volume;
  • the volume resistivity is compared with preset evaluation parameters to obtain a defect detection result of the buffer layer.
  • the calculation formula of the compressive deformation ratio of the buffer layer is:
  • eta represents the compressive deformation ratio of the buffer layer
  • V A represents the first volume of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed
  • V B represents the first volume of the buffer layer when the insulation shield The second volume of the deformed portion when the buffer layer and the corrugated sheath are deformed due to force.
  • the calculation formula of the first volume when the buffer layer is not deformed is:
  • V A represents the first volume of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed;
  • ⁇ A represents the critical point of contact between the corrugated sheath and the buffer layer.
  • Angle; d len represents the pitch of the wrinkles;
  • d O'C represents the first outer radius of the cable under test containing a buffer layer;
  • d O'B represents the diameter of the cable under test containing a shielding layer Second outside radius.
  • V B represents the second volume of the deformed part of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is deformed under force
  • ⁇ A represents the contact between the corrugated sheath and the buffer layer The angle of the critical point
  • d O'C represents the first outer radius of the cable under test containing the buffer layer
  • d OA represents the inner radius of the wrinkled sheath
  • f ( ⁇ ) represents the interpolation function
  • d OO' represents the distance between the center of the circle of the wrinkle sheath and the center of the cable core to be tested
  • d OO′ d OA -d O'B -d BB'
  • d O'B represents the shielded layer
  • d BB' represents the thickness of the thinnest point of the buffer layer.
  • obtaining the voltage, current, electrode area, electrode distance and initial electrode distance of the buffer layer when it reaches the compressive deformation ratio specifically includes:
  • An electrode package with air extracted but without the buffer layer is placed between the upper and lower electrodes of the volume resistivity detection device, and a low-voltage DC voltage is applied to control the upper electrode to slowly decrease at a first speed until the upper and lower electrodes are in contact with each other.
  • the electrode packages are in full contact, and the distance between the upper and lower electrodes at this time is obtained as the initial electrode distance;
  • the voltage, current, electrode area between the upper and lower electrodes and the electrode distance between the upper and lower electrodes after the preset time are obtained.
  • the calculation formula of the volume resistivity of the buffer layer is:
  • ⁇ represents the volume resistivity of the buffer layer
  • eta represents the compressive deformation ratio of the buffer layer
  • U represents the voltage between the upper and lower electrodes
  • S represents the electrode area
  • I represents the current
  • d 1 represents the initial electrode distance
  • d 2 represents the electrode distance.
  • the volume resistivity is compared with preset evaluation parameters to obtain the defect detection results of the buffer layer, which specifically includes:
  • volume resistivity is less than or equal to the evaluation parameter, it is determined that there is no defect in the buffer layer
  • volume resistivity is greater than the evaluation parameter, it is determined that the buffer layer is defective.
  • An embodiment of the present invention also provides a defect detection device for a cable buffer layer, including:
  • the first acquisition module is used to obtain the specification parameters of the wrinkled sheath of the cable to be tested; wherein the specification parameters include the inner radius of the wrinkled sheath, the first outer radius of the cable to be tested including the buffer layer, the shielding layer The second outer radius, wrinkle pitch, wrinkle depth and thickness of the thinnest point of the buffer layer of the cable to be tested;
  • a first volume calculation module configured to calculate a volume based on the first outer radius of the cable to be tested including the buffer layer, the second outer radius of the cable to be tested including the shielding layer, and the wrinkle pitch. Obtain the first volume of the buffer layer when it is not deformed;
  • the second volume calculation module is used to calculate the inner radius of the corrugated sheath, the first outer radius of the cable under test including the buffer layer, and the second outer radius of the cable under test including the shielding layer.
  • the radius and the thickness of the thinnest point of the buffer layer are used to calculate the second volume of the deformed portion when the buffer layer is deformed under force;
  • a compression deformation ratio calculation module configured to calculate the compression deformation ratio of the buffer layer based on the first volume and the second volume
  • the second acquisition module is used to acquire the voltage, current, electrode area, electrode distance and initial electrode distance of the buffer layer when it reaches the compressive deformation ratio;
  • a volume resistivity calculation module configured to calculate the volume resistivity of the buffer layer based on the voltage, the current, the electrode area, the electrode distance, and the initial electrode distance;
  • a defect detection module is used to compare the volume resistivity with preset evaluation parameters to obtain a defect detection result of the buffer layer.
  • An embodiment of the present invention also provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor.
  • a terminal device including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor.
  • the processor executes the computer program, the above-mentioned The method for detecting defects in the cable buffer layer described in any one of the above.
  • Embodiments of the present invention also provide a computer-readable storage medium.
  • the computer-readable storage medium includes a stored computer program.
  • the device where the computer-readable storage medium is located is controlled to perform any of the above tasks.
  • the beneficial effects of the defect detection method, device, equipment and storage medium of the cable buffer layer are: by obtaining the specification parameters of the wrinkle sheath of the cable to be tested, the cable buffer layer is calculated The first volume when deformation does not occur and the second volume of the deformed portion when the cable buffer layer is deformed under force, to obtain the pressure deformation ratio of the buffer layer, and then obtain the voltage, current, and voltage of the buffer layer when it reaches the pressure deformation ratio.
  • the volume resistivity of the buffer layer is calculated based on the electrode area, electrode distance and initial electrode distance.
  • the volume resistivity is compared with the preset evaluation parameters to obtain the defect detection results of the buffer layer.
  • the embodiment of the present invention considers the covering, moisture and pressure conditions of the cable buffer layer wrapping tape, and can accurately calculate the volume resistivity of the cable buffer layer, and then accurately determine whether there is a quality defect in the cable buffer layer based on the volume resistivity.
  • Figure 1 is a schematic flow chart of a preferred embodiment of a cable buffer layer defect detection method provided by the present invention
  • Figure 2 is a schematic structural diagram of a cable provided by an embodiment of the present invention.
  • Figure 3 is a cross-sectional view of the cable plane without contact between the corrugated sheath and the buffer layer above the cable provided by the embodiment of the present invention
  • Figure 4 is a cross-sectional view of the cable plane where there is contact between the corrugated sheath and the buffer layer above the cable provided by the embodiment of the present invention
  • Figure 6 is a schematic structural diagram of a preferred embodiment of a cable buffer layer defect detection device provided by the present invention.
  • Figure 7 is a schematic structural diagram of a preferred embodiment of a terminal device provided by the present invention.
  • FIG. 1 is a schematic flow chart of a preferred embodiment of a cable buffer layer defect detection method provided by the present invention.
  • the method for detecting defects in the cable buffer layer includes:
  • the specification parameters include the inner radius of the wrinkle sheath, the first outer radius of the cable to be tested including a buffer layer, the first outer radius of the cable to be tested including a shielding layer
  • the second outer radius of the cable the pitch of the wrinkles, the depth of the wrinkles and the thickness of the thinnest point of the buffer layer
  • the first outer radius of the cable to be tested including the buffer layer the second outer radius of the cable to be tested including the shielding layer and the buffer layer
  • the thickness of the thinnest point is calculated to obtain the second volume of the deformed part when the buffer layer is deformed under force
  • S6 calculate the volume resistivity of the buffer layer according to the voltage, the current, the electrode area, the electrode distance and the initial electrode distance;
  • step S1 refer to Figure 2, which is a schematic structural diagram of a cable provided by an embodiment of the present invention.
  • the cable according to the embodiment of the present invention includes a battery core (conductor) 10, a shielding layer 20, a corrugated sheath 40, and a buffer layer 30 disposed between the shielding layer 20 and the corrugated sheath 40.
  • the cable can be determined according to the factory test report of the cable or As a result of the actual measurement, the specifications and parameters of the cable wrinkle sheath were measured.
  • the specification parameters include the inner radius d OA of the corrugated sheath, the first outer radius d O'C of the cable to be tested including a buffer layer, and the second outer radius d of the cable to be tested including a shielding layer.
  • O'B wrinkle pitch d len , wrinkle depth d dep and thickness of the thinnest point of the buffer layer d BB' .
  • Figure 3 is a cross-sectional view of the cable plane where there is no contact between the corrugated sheath above the cable and the buffer layer provided by the embodiment of the present invention.
  • Figure 4 is a cross-sectional view of the corrugated sheath and buffer layer above the cable provided by the embodiment of the present invention. Cross-section of the cable plane with contact between buffer layers. 41 represents the outside of the corrugated sheath, 42 represents the inside of the corrugated sheath, 31 represents the outside of the buffer layer, and 32 represents the inside of the buffer layer.
  • the compression of the buffer layer within the entire length of the cable can be characterized by the compression of the buffer layer within a single wrinkle pitch. Therefore, calculating the compression deformation ratio of the buffer layer within a single wrinkle pitch can characterize the compression of the buffer layer within the entire length of the cable.
  • the calculation formula of the compressive deformation ratio of the buffer layer is:
  • eta represents the compressive deformation ratio of the buffer layer
  • V A represents the first volume of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed
  • V B represents the first volume of the buffer layer when the insulation shield The second volume of the deformed portion when the buffer layer and the corrugated sheath are deformed due to force.
  • FIG. 3 is the center position of the cable core, and the critical points of contact between the buffer layer and the wrinkle sheath are marked as A and A'.
  • V A is the first volume of the buffer layer wrapping tape that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed;
  • V B is the conductive part between the insulation shield and the corrugated sheath.
  • the calculation formula of the first volume when the buffer layer is not deformed is:
  • V A represents the first volume of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed;
  • ⁇ A represents the critical point of contact between the corrugated sheath and the buffer layer.
  • Angle; d len represents the pitch of the wrinkles;
  • d O'C represents the first outer radius of the cable under test containing a buffer layer;
  • d O'B represents the diameter of the cable under test containing a shielding layer Second outside radius.
  • the calculation formula for the second volume of the deformed part when the buffer layer is deformed under force is:
  • V B represents the second volume of the deformed part when the buffer layer is deformed under force
  • ⁇ A represents the angle of the critical point of contact between the wrinkle sheath and the buffer layer
  • d O'C represents the buffer-containing layer of the first outer radius of the cable to be tested
  • d OA represents the inner radius of the wrinkled sheath
  • f( ⁇ ) represents the interpolation function
  • dOO ' represents the distance between the center of the circle of the wrinkled sheath and the cable to be tested The distance between the center points of the wire cores
  • d OO′ d OA -d O'B -d BB'
  • d O'B represents the second outer radius of the cable under test containing the shielding layer
  • d BB ' represents the thickness of the thinnest point of the buffer layer.
  • the intersection point with the outside of the insulation shield is marked as B; the intersection point with the outside of the buffer layer is marked as C; the intersection point with the inside of the wrinkle sheath is marked as D; the wrinkle within a single wrinkle pitch
  • the critical positions of contact between the sheath and the buffer layer are points E and F respectively; points E and F are rayed on their respective radial planes toward their respective radial centers and intersect with two points G and H on the outside of the insulation shield.
  • d len is the wrinkle pitch
  • d OD is the minimum radius inside the wrinkle sheath
  • d O'B is the second outer radius of the cable with insulation and shielding
  • d O'C is the first outer radius of the cable with buffer layer
  • d OC is the distance from the origin O to point C
  • ⁇ A is the angle at the critical point A where the wrinkle sheath contacts the buffer layer.
  • the interpolation base point can be determined, and the interpolation base points of the same model and batch of cables provided by the supplier in different wrinkles can be measured at multiple points.
  • the coordinates of the interpolation data points ( ⁇ k , 0, z k ), k 1,...,r; r is the number of interpolation data points required by the selected interpolation method. From this we get the approximate surface in The expression of the interpolation function within the interval is f( ⁇ ).
  • the double integral of the above expression can be simplified to obtain a single-variable definite integral expression. It can be found that the integrals before and after the above simplification are not guaranteed to have analytical solutions, and numerical integration methods can be used to solve them. Numerical integration methods such as the trapezoidal method, Simpson's rule, Newton-Cortez formula, Romberg method, Gauss integration method, Chebyshev integration method and Monte Carlo integration method and their improved forms can be used to calculate the above integrals, so that The approximate value of the compressive deformation ratio of the buffer layer within a single wrinkle pitch is obtained, and then the approximate value of the compressive deformation ratio of the buffer layer of the entire cable is obtained.
  • Numerical integration methods such as the trapezoidal method, Simpson's rule, Newton-Cortez formula, Romberg method, Gauss integration method, Chebyshev integration method and Monte Carlo integration method and their improved forms can be used to calculate the above integrals, so that The approximate value of the compressive deformation ratio of the buffer layer within a single wrinkle pitch is
  • S5 is to obtain the voltage, current, electrode area, electrode distance and initial electrode distance of the buffer layer when it reaches the compressive deformation ratio, specifically including:
  • S51 Place an electrode package with air extracted but without the buffer layer between the upper and lower electrodes of the volume resistivity detection device, apply a low-voltage DC voltage, and control the upper electrode to slowly descend at a first speed until the upper and lower electrodes are The electrode is in full contact with the electrode package, and the distance between the upper and lower electrodes at this time is obtained as the initial electrode distance;
  • S52 Place the electrode package containing the buffer layer that extracts air between the upper and lower electrodes of the volume resistivity detection device, and applies a low-voltage DC voltage to control the upper electrode to slowly decline at the first speed until the upper and lower electrodes Full contact with the electrode packaging;
  • S55 Obtain the voltage, current, electrode area between the upper and lower electrodes and the electrode distance between the upper and lower electrodes after the preset time.
  • an electrode package that extracts air but does not contain a buffer layer is placed between the upper and lower electrodes of the volume resistivity detection device, and the "reset" function of the volume resistivity detection device is selected, and low-voltage direct current is applied between the upper and lower electrodes of the detection device.
  • the voltage is controlled by the transmission mechanism to slowly decrease on the upper electrode.
  • the ammeter reading exceeds the short-circuit threshold ⁇ sc , it is considered that the upper and lower electrodes have fully contacted the electrode package, and the position sensor reads the distance between the two electrodes as the initial electrode distance d 1 . Stop applying the voltage between the upper and lower electrodes, and the transmission mechanism controls the upper electrode of the volume resistivity detection device to slowly rise to the starting position.
  • Disassemble the outer sheath and corrugated sheath of the cable quickly cut the wrapped buffer layer to the appropriate size, and put it into the electrode package.
  • the buffer layer needs to maintain the original state of the wrapping in the cable, and the surface can cover the conductor electrodes on both sides of the electrode package.
  • the air in the package is extracted and sealed to be stored as a packaged buffer layer sample. Due to the vacuum state of the encapsulated buffer layer, on the one hand, it can maintain the wrapping and covering state without loosening and falling off; on the other hand, it can prevent the buffer layer from getting damp during storage.
  • the relative error of the two current measurement values I 1 and I 2 sampled at close time is less than the path threshold ⁇ loop, that is When , it can be considered that the electrode and the encapsulated buffer layer sample have fully contacted, and the position sensor reads the distance d 2 between the two electrodes.
  • the transmission mechanism controls the upper electrode to descend slowly at a slower speed, and the sensor continuously reads the distance d c between the two electrodes.
  • the calculation formula for the volume resistivity of the buffer layer is:
  • ⁇ represents the volume resistivity of the buffer layer
  • eta represents the compressive deformation ratio of the buffer layer
  • U represents the voltage between the upper and lower electrodes
  • S represents the electrode area
  • I represents the current
  • d 1 represents the initial electrode distance
  • d 2 represents the electrode distance.
  • the volume resistivity is compared with preset evaluation parameters to obtain the defect detection result of the buffer layer, which specifically includes:
  • the calculated volume resistivity is compared with the preset evaluation parameters. When the volume resistivity is less than or equal to the evaluation parameter, it is determined that there is no defect in the buffer layer; when the volume resistivity is greater than the evaluation parameter, it is determined that the buffer layer has no defects. The buffer layer is defective.
  • interpolation calculation is performed to obtain the interpolation function expression f ( ⁇ ).
  • Disassemble the cable outer sheath and corrugated sheath quickly cut the wrapped buffer layer to the appropriate size, and put it into the electrode package.
  • the buffer layer needs to maintain the original state of the wrapping in the cable, and the surface can cover the conductor electrodes on both sides of the electrode package.
  • the air in the package is extracted and sealed to be stored as a packaged buffer layer sample. Due to the vacuum state of the encapsulated buffer layer, on the one hand, it can maintain the wrapping and covering state without loosening and falling off; on the other hand, it can prevent the buffer layer from getting damp during storage.
  • the relative error of the two current measurement values I 1 and I 2 sampled at close time is less than the path threshold ⁇ loop, that is When , it can be considered that the electrode and the encapsulated buffer layer sample have fully contacted, and the position sensor reads the distance d 2 between the two electrodes.
  • the transmission mechanism controls the upper electrode to descend slowly at a slower speed, and the sensor continuously reads the distance d c between the two electrodes.
  • the volume resistivity requirement in JB/T 10259-2014 "Water-blocking Tape for Electric Cables and Optical Cables" is not to exceed 1000 ⁇ m. Therefore, if the volume resistivity of the cable buffer layer is qualified, then the cable buffer layer does not have quality defects. .
  • the present invention also provides a cable buffer layer defect detection device, which can implement all the processes of the cable buffer layer defect detection method in the above embodiment.
  • FIG. 6 is a schematic structural diagram of a preferred embodiment of a cable buffer layer defect detection device provided by the present invention.
  • the defect detection device of the cable buffer layer includes:
  • the first acquisition module 601 is used to obtain the specification parameters of the wrinkle sheath of the cable to be tested; wherein the specification parameters include the inner radius of the wrinkle sheath, the first outer radius of the cable to be tested including the buffer layer, the shielding The second outer radius of the layer of the cable to be tested, the wrinkle pitch, the wrinkle depth and the thinnest point thickness of the buffer layer;
  • the first volume calculation module 602 is configured to calculate based on the first outer radius of the cable under test including the buffer layer, the second outer radius of the cable under test including the shielding layer, and the wrinkle pitch, Calculate the first volume of the buffer layer when it is not deformed;
  • the second volume calculation module 603 is used to calculate the inner radius of the corrugated sheath, the first outer radius of the cable under test including the buffer layer, and the second outer radius of the cable under test including the shielding layer.
  • the outer radius and the thickness of the thinnest point of the buffer layer are used to calculate the second volume of the deformed portion when the buffer layer is deformed under force;
  • the compressive deformation ratio calculation module 604 is used to calculate the compressive deformation ratio of the buffer layer based on the first volume and the second volume;
  • the second acquisition module 605 is used to acquire the voltage, current, electrode area, electrode distance and initial electrode distance of the buffer layer when it reaches the compressive deformation ratio;
  • the volume resistivity calculation module 606 is used to calculate the volume resistivity of the buffer layer according to the voltage, the current, the electrode area, the electrode distance and the initial electrode distance;
  • the defect detection module 607 is used to compare the volume resistivity with preset evaluation parameters to obtain the defect detection result of the buffer layer.
  • the calculation formula of the compressive deformation ratio of the buffer layer is:
  • eta represents the compressive deformation ratio of the buffer layer
  • V A represents the first volume of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed
  • V B represents the first volume of the buffer layer when the insulation shield The second volume of the deformed portion when the buffer layer and the corrugated sheath are deformed due to force.
  • the calculation formula of the first volume when the buffer layer is not deformed is:
  • V A represents the first volume of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is not deformed;
  • ⁇ A represents the critical point of contact between the corrugated sheath and the buffer layer.
  • Angle; d len represents the pitch of the wrinkles;
  • d O'C represents the first outer radius of the cable under test containing a buffer layer;
  • d O'B represents the diameter of the cable under test containing a shielding layer Second outside radius.
  • the calculation formula for the second volume of the deformed part when the buffer layer is deformed under force is:
  • V B represents the second volume of the deformed part of the buffer layer that plays a conductive role between the insulation shield and the corrugated sheath when it is deformed under force
  • ⁇ A represents the contact between the corrugated sheath and the buffer layer The angle of the critical point
  • d O'C represents the first outer radius of the cable under test containing the buffer layer
  • d OA represents the inner radius of the wrinkled sheath
  • f ( ⁇ ) represents the interpolation function
  • d OO' represents the distance between the center of the circle of the wrinkle sheath and the center of the cable core to be tested
  • d OO′ d OA -d O'B -d BB ′
  • d O'B represents the shielded layer
  • d BB' represents the thickness of the thinnest point of the buffer layer.
  • the second acquisition module 605 is specifically used for:
  • An electrode package with air extracted but without the buffer layer is placed between the upper and lower electrodes of the volume resistivity detection device, and a low-voltage DC voltage is applied to control the upper electrode to slowly decrease at a first speed until the upper and lower electrodes are in contact with each other.
  • the electrode packages are in full contact, and the distance between the upper and lower electrodes at this time is obtained as the initial electrode distance;
  • the voltage, current, electrode area between the upper and lower electrodes and the electrode distance between the upper and lower electrodes after the preset time are obtained.
  • the calculation formula of the volume resistivity of the buffer layer is:
  • ⁇ represents the volume resistivity of the buffer layer
  • eta represents the compressive deformation ratio of the buffer layer
  • U represents the voltage between the upper and lower electrodes
  • S represents the electrode area
  • I represents the current
  • d 1 represents the initial electrode distance
  • d 2 represents the electrode distance.
  • the defect detection module 607 is specifically used for:
  • volume resistivity is less than or equal to the evaluation parameter, it is determined that there is no defect in the buffer layer
  • volume resistivity is greater than the evaluation parameter, it is determined that the buffer layer is defective.
  • the working principle, control process and technical effect of the defect detection device for the cable buffer layer provided by the embodiment of the present invention are the same as those of the defect detection method of the cable buffer layer in the above embodiment, and will not be discussed here. Repeat.
  • the defect detection device of the cable buffer layer includes: a processor, wherein the processor is configured to execute the above program module in the memory, including: a first acquisition module 601, a first volume calculation module 602, a second Volume calculation module 603, pressure deformation ratio calculation module 604, second acquisition module 605, volume resistivity calculation module 606 and defect detection module 607.
  • FIG. 7 is a schematic structural diagram of a preferred embodiment of a terminal device provided by the present invention.
  • the terminal device includes a processor 701, a memory 702, and a computer program stored in the memory 702 and configured to be executed by the processor 701.
  • the processor 701 executes the computer program, any of the above implementations are implemented. Defect detection method of cable buffer layer described in the example.
  • the computer program can be divided into one or more modules/units (such as computer program 1, computer program 2,...), and the one or more modules/units are stored in the memory 702, and executed by the processor 701 to complete the present invention.
  • the one or more modules/units may be a series of computer program instruction segments capable of completing specific functions. The instruction segments are used to describe the execution process of the computer program in the terminal device.
  • the processor 701 can be a central processing unit (Central Processing Unit, CPU), or other general-purpose processor, digital signal processor (Digital Signal Processor, DSP), application specific integrated circuit (Application Specific Integrated Circuit, ASIC), Field-Programmable Gate Array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc.
  • the general-purpose processor can be a microprocessor, or the processor 701 can also It is any conventional processor.
  • the processor 701 is the control center of the terminal device and uses various interfaces and lines to connect various parts of the terminal device.
  • the memory 702 mainly includes a program storage area and a data storage area, where the program storage area can store an operating system, at least one application program required for a function, etc., and the data storage area can store related data, etc.
  • the memory 702 can be a high-speed random access memory, or a non-volatile memory, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (Secure Digital, SD) card and a flash memory. Card (Flash Card), etc., or the memory 702 can also be other volatile solid-state storage devices.
  • the above-mentioned terminal device may include, but is not limited to, a processor and a memory.
  • a processor and a memory.
  • the structural schematic diagram in Figure 7 is only an example of the above-mentioned terminal device and does not constitute a limitation on the above-mentioned terminal device. More or fewer components than shown, or combinations of certain components, or different components may be included.
  • Embodiments of the present invention also provide a computer-readable storage medium.
  • the computer-readable storage medium includes a stored computer program.
  • the computer program is running, the device where the computer-readable storage medium is located is controlled to perform any of the above tasks.
  • a method for detecting defects in a cable buffer layer according to an embodiment.
  • Embodiments of the present invention provide a method, device, equipment and storage medium for defect detection of a cable buffer layer.
  • the first volume and the cable when the cable buffer layer is not deformed are calculated.
  • the second volume of the deformed part of the buffer layer when it is deformed under force is used to obtain the pressure deformation ratio of the buffer layer, and then the voltage, current, electrode area, electrode distance and initial electrode distance of the buffer layer when it reaches the pressure deformation ratio are obtained.
  • the volume resistivity of the buffer layer is calculated, and the volume resistivity is compared with the preset evaluation parameters to obtain the defect detection results of the buffer layer.
  • the embodiment of the present invention considers the covering, moisture and pressure conditions of the cable buffer layer wrapping tape, and can accurately calculate the volume resistivity of the cable buffer layer, and then accurately determine whether there is an ablation defect in the cable buffer layer based on the volume resistivity.
  • the device embodiments described above are only illustrative.
  • the units described as separate components may or may not be physically separated.
  • the components shown as units may or may not be physically separate.
  • the unit can be located in one place, or it can be distributed across multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.
  • the connection relationship between modules indicates that there are communication connections between them, which can be implemented as one or more communication buses or signal lines. Persons of ordinary skill in the art can understand and implement the method without any creative effort.

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Abstract

一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质，该方法包括获取待测电缆皱纹护套（40）的规格参数；计算得到缓冲层（30）未发生形变时的第一体积和电缆缓冲层（30）受力发生形变时变形部分的第二体积；根据第一体积和第二体积计算得到缓冲层（30）的受压形变比率；获取缓冲层（30）在达到受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；计算得到缓冲层（30）的体积电阻率；将体积电阻率与预设的评价参数进行比对，以得到缓冲层（30）的缺陷检测结果。该方法考虑电缆缓冲层绕包带的搭盖、受潮和受压情况，能够准备计算出电缆缓冲层的体积电阻率，进而可以根据体积电阻率准确判断电缆缓冲层是否存在质量缺陷。

Description

一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质 技术领域
本发明涉及电缆技术领域，尤其涉及一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质。
背景技术
在电缆输电线路中，电缆的缓冲层不但承担着机械力缓冲的功能，更重要的是实现电缆绝缘屏蔽与接地金属护套之间的电气连接。而近年来，高压电力电缆缓冲层烧蚀引发的故障数量逐渐增多，缓冲层烧蚀隐患已成为威胁电网安全的重要隐患之一。缓冲层的烧蚀隐患主要有局部放电烧蚀、电流致热烧蚀以及电化学烧蚀等情况，这些隐患情况均是由于缓冲层受潮后体积电阻率严重增大引起的，体积电阻率增大导致绝缘屏蔽与金属护套无法形成良好的电气连接，从而引发故障。因此，通过计算缓冲层的体积电阻率可以直接反映电缆是否存在质量缺陷。
目前的体积电阻率检测方法仅适用于尚未在电缆上绕包的成品缓冲层，并非从成品电缆中取出的缓冲层绕包带，而电力电缆生产工序中，在缓冲层绕包之后仍有皱纹金属套制作、气密性试验等众多过程，这样造成在后续生产过程中导致缓冲层受潮质量下降的情况，无法在成品缓冲层检测阶段发现。将待测的成品缓冲层暴露于空气中，与电缆内部相对密闭的环境差异较大，导致检测结果无法准确反映电缆中缓冲层绕包带的真实情况。另外，目前的体积电阻率检测方法仅适用于单层缓冲层的检测，而实际电缆中缓冲层绕包带一般为多层相互搭盖的形式，外层相对暴露在空气中受潮可能性较大，内层受潮可能性较小。实在际检测工作开展时，对缓冲层绕包带内层和外层取样的检测结论不一致时有发生，导致检测结果无法准确反映电缆中缓冲层绕包带的真实情况。目前的体积电阻率检测方法考虑缓冲层所受压力的大小对缓冲层的体积电阻率的影响仍很初级，无法准确计算体积电阻率，导致无法准确判断电缆缓冲层是否存在质量缺陷。
发明内容
本发明实施例所要解决的技术问题在于，提供一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质，能够准确计算出电缆缓冲层的体积电阻率，进而可以根据体积电阻率准确判断电缆缓冲层是否存在质量缺陷。
为了实现上述目的，本发明实施例提供了一种电缆缓冲层的缺陷检测方法，包括：
获取待测电缆皱纹护套的规格参数；其中，所述规格参数包括皱纹护套的内侧半径、含缓冲层的所述待测电缆的第一外侧半径、含屏蔽层的所述待测电缆的第二外侧半径、皱纹节距、皱纹深度和缓冲层的最薄点厚度；
根据所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述皱纹节距，计算得到所述缓冲层未发生形变时的第一体积；
根据所述皱纹护套的内侧半径、所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述 待测电缆的第二外侧半径和所述缓冲层的最薄点厚度，计算得到所述缓冲层受力发生形变时变形部分的第二体积；
根据所述第一体积和所述第二体积计算得到所述缓冲层的受压形变比率；
获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；
根据所述电压、所述电流、所述电极面积、所述电极距离以及所述初始电极距离，计算得到所述缓冲层的体积电阻率；
将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果。
作为上述方案的改进，所述缓冲层的受压形变比率的计算公式为：
Figure PCTCN2022111004-appb-000001
其中，η表示所述缓冲层的受压形变比率；V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积。
作为上述方案的改进，所述缓冲层未发生形变时的第一体积的计算公式为：
Figure PCTCN2022111004-appb-000002
其中，V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d len表示所述皱纹节距；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径。
作为上述方案的改进，所述缓冲层受力发生形变时变形部分的第二体积的计算公式为：
Figure PCTCN2022111004-appb-000003
其中，V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d OA表示所述皱纹护套的内侧半径；f(ρ)表示插值函数；d OO’表示所述皱纹护套的圆心与所述待测电缆线芯的圆心之间的距离，且d OO′＝d OA-d O′B-d BB′，d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径，d BB’表示所述缓冲层的最薄点厚度。
作为上述方案的改进，所述获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离，具体包括：
在体积电阻率检测装置的上、下电极之间放入抽出空气但不含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触，获取此时上、下电极之 间的距离，作为初始电极距离；
在体积电阻率检测装置的上、下电极之间放入抽出空气且含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触；
控制上电极以第二速度缓慢下降，直至达到所述缓冲层的受压形变比率；其中，所述第二速度小于所述第一速度；
逐步升高所述上、下电极之间的直流电压，直至电流达到通路电流阈值，并维持预设时间；
获取所述预设时间后的上、下电极之间的电压、电流、电极面积以及所述上、下电极之间的电极距离。
作为上述方案的改进，所述缓冲层的体积电阻率的计算公式为：
Figure PCTCN2022111004-appb-000004
其中，σ表示所述缓冲层的体积电阻率；η表示所述缓冲层的受压形变比率；U表示上下电极之间的电压；S表示电极面积；I表示电流；d 1表示初始电极距离；d 2表示电极距离。
作为上述方案的改进，所述将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果，具体包括：
当所述体积电阻率小于或等于所述评价参数时，判定所述缓冲层不存在缺陷；
当所述体积电阻率大于所述评价参数时，判定所述缓冲层存在缺陷。
本发明实施例还提供了一种电缆缓冲层的缺陷检测装置，包括：
第一获取模块，用于获取待测电缆皱纹护套的规格参数；其中，所述规格参数包括皱纹护套的内侧半径、含缓冲层的所述待测电缆的第一外侧半径、含屏蔽层的所述待测电缆的第二外侧半径、皱纹节距、皱纹深度和缓冲层的最薄点厚度；
第一体积计算模块，用于根据所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述皱纹节距，计算得到所述缓冲层未发生形变时的第一体积；
第二体积计算模块，用于根据所述皱纹护套的内侧半径、所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述缓冲层的最薄点厚度，计算得到所述缓冲层受力发生形变时变形部分的第二体积；
受压形变比率计算模块，用于根据所述第一体积和所述第二体积计算得到所述缓冲层的受压形变比率；
第二获取模块，用于获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；
体积电阻率计算模块，用于根据所述电压、所述电流、所述电极面积、所述电极距离以及所述初始电极距离，计算得到所述缓冲层的体积电阻率；
缺陷检测模块，用于将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果。
本发明实施例还提供了一种终端设备，包括处理器、存储器以及存储在所述存储器中且被配置为由所 述处理器执行的计算机程序，所述处理器执行所述计算机程序时实现上述任一项所述的电缆缓冲层的缺陷检测方法。
本发明实施例还提供了一种计算机可读存储介质，所述计算机可读存储介质包括存储的计算机程序，其中，在所述计算机程序运行时控制所述计算机可读存储介质所在设备执行上述任一项所述的电缆缓冲层的缺陷检测方法。
相对于现有技术，本发明实施例提供的一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质的有益效果在于：通过获取待测电缆皱纹护套的规格参数，计算得到电缆缓冲层未发生形变时的第一体积和电缆缓冲层受力发生形变时变形部分的第二体积，以得到缓冲层的受压形变比率，再获取缓冲层在达到受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离，计算得到缓冲层的体积电阻率，将体积电阻率与预设的评价参数进行比对，得到缓冲层的缺陷检测结果。本发明实施例考虑电缆缓冲层绕包带的搭盖、受潮和受压情况，能够准确计算出电缆缓冲层的体积电阻率，进而可以根据体积电阻率准确判断电缆缓冲层是否存在质量缺陷。
附图说明
图1是本发明提供的一种电缆缓冲层的缺陷检测方法的一个优选实施例的流程示意图；
图2是本发明实施例提供的电缆的结构示意图；
图3是本发明实施例提供的电缆上方皱纹护套与缓冲层之间未接触的电缆平面的截面图；
图4是本发明实施例提供的电缆上方皱纹护套与缓冲层之间存在接触的电缆平面的截面图；
图5是本发明实施例提供的皱纹护套与缓冲层接触面在θ＝θ P平面的截面图；
图6是本发明提供的一种电缆缓冲层的缺陷检测装置的一个优选实施例的结构示意图；
图7是本发明提供的一种终端设备的一个优选实施例的结构示意图。
具体实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
请参阅图1，图1是本发明提供的一种电缆缓冲层的缺陷检测方法的一个优选实施例的流程示意图。所述电缆缓冲层的缺陷检测方法，包括：
S1，获取待测电缆皱纹护套的规格参数；其中，所述规格参数包括皱纹护套的内侧半径、含缓冲层的所述待测电缆的第一外侧半径、含屏蔽层的所述待测电缆的第二外侧半径、皱纹节距、皱纹深度和缓冲层的最薄点厚度；
S2，根据所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述皱纹节距，计算得到所述缓冲层未发生形变时的第一体积；
S3，根据所述皱纹护套的内侧半径、所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的 所述待测电缆的第二外侧半径和所述缓冲层的最薄点厚度，计算得到所述缓冲层受力发生形变时变形部分的第二体积；
S4，根据所述第一体积和所述第二体积计算得到所述缓冲层的受压形变比率；
S5，获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；
S6，根据所述电压、所述电流、所述电极面积、所述电极距离以及所述初始电极距离，计算得到所述缓冲层的体积电阻率；
S7，将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果。
具体地，在步骤S1中，参见图2，图2是本发明实施例提供的电缆的结构示意图。本发明实施例所述的电缆包括电芯(导体)10、屏蔽层20、皱纹护套40以及设于屏蔽层20和皱纹护套40之间的缓冲层30，可以根据电缆的出厂试验报告或实测结果，测量得到电缆皱纹护套的规格参数。其中，所述规格参数包括皱纹护套的内侧半径d OA、含缓冲层的所述待测电缆的第一外侧半径d O’C、含屏蔽层的所述待测电缆的第二外侧半径d O’B、皱纹节距d len、皱纹深度d dep和缓冲层的最薄点厚度d BB’。参见图3和图4，图3是本发明实施例提供的电缆上方皱纹护套与缓冲层之间未接触的电缆平面的截面图，图4是本发明实施例提供的电缆上方皱纹护套与缓冲层之间存在接触的电缆平面的截面图。41表示皱纹护套外侧，42表示皱纹护套内侧，31表示缓冲层外侧，32表示缓冲层内侧。
需要说明的是，由于皱纹护套存在峰谷位置，为计算皱纹护套对缓冲层的施压情况，需要作出以下符合工程实际的基本假设：
假定每个皱纹节距内缓冲层与皱纹护套的接触状态是近似相同的；
假定皱纹的倾斜角度对缓冲层受压情况的影响可以忽略。
此时，电缆全长范围内缓冲层受压情况可以通过单个皱纹节距内缓冲层的受压情况进行表征。因此，计算单个皱纹节距内缓冲层受压形变比率即可表征电缆全长范围内缓冲层受压情况。
在另一个优选实施例中，所述缓冲层的受压形变比率的计算公式为：
Figure PCTCN2022111004-appb-000005
其中，η表示所述缓冲层的受压形变比率；V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积。
具体地，考虑到实际皱纹护套与缓冲层接触面为一个空间曲面，在电缆径向平面内，以皱纹护套圆心位置O为原点，如图3所示可建立ρ-θ平面极坐标。O’为电缆线芯圆心位置，缓冲层与皱纹护套接触的临界点记为A和A’。参见图5，图5是本发明实施例提供的皱纹护套与缓冲层接触面在θ＝θ P平面的截面图。如图5所示，在ρ-θ平面坐标基础上，以电缆轴向方向为Z方向可建立三维坐标系，图中虚线部分即为缓冲层与皱纹护套接触面示意。显然，在一个皱纹节距内，缓冲层受压形变比率可用下式计算：
Figure PCTCN2022111004-appb-000006
其中，V A为在绝缘屏蔽与皱纹护套之间起导电作用部分的缓冲层绕包带未发生变形时的第一体积；V B为在绝缘屏蔽与皱纹护套之间起导电作用部分的缓冲层受力发生形变时变形部分的第二体积。V B与皱纹护套内侧曲面函数紧密相关，记其为z＝f(ρ，θ)，易知，f(ρ，θ)的解析表达式难以得到。但是通过z＝f(ρ，θ)曲面的一个连续可微近似函数z＝f(ρ)可以近似计算相应的体积。由于皱纹护套内侧曲面在z＝0平面上的投影以θ＝0方向的直线对称，且单个皱纹节距内的内侧曲面以z＝0平面对称，故计算V B的值只需要在π≥θ≥0，Z≥0区间完成体积计算乘以4倍即可。
在另一个优选实施例中，所述缓冲层未发生形变时的第一体积的计算公式为：
Figure PCTCN2022111004-appb-000007
其中，V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d len表示所述皱纹节距；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径。
在另一个优选实施例中，所述缓冲层受力发生形变时变形部分的第二体积的计算公式为：
Figure PCTCN2022111004-appb-000008
其中，V B表示所述缓冲层受力发生形变时变形部分的第二体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d OA表示所述皱纹护套的内侧半径；f(ρ)表示插值函数；d OO’表示所述皱纹护套的圆心与所述待测电缆线芯的圆心之间的距离，且d OO′＝d OA-d O′B-d BB′，d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径，d BB’表示所述缓冲层的最薄点厚度。
具体地，如图5所示，记Ω ρθ为接触曲面在z＝0平面上的投影，对于任意点P∈Ω ρθ，记其坐标为(ρ P，θ P，0)。在z＝0平面上，从原点O向点P做射线，与绝缘屏蔽外侧交点记为B；与缓冲层外侧交点记为C；与皱纹护套内侧交点记为D；单个皱纹节距内皱纹护套与缓冲层接触的临界位置分别为E、F两点；E、F两点分别在各自的径向平面上向各自的径向圆心做射线与绝缘屏蔽外侧交与G、H两点。则，V A与θ＝θ P平面的截面如图5中EFHG包围部分所示；V B与θ＝θ P平面的截面如图5中ECFD包围部分所示。在电缆轴向方向上，通过对皱纹曲线EDF进行近似，可得到皱纹护套与缓冲层接触曲面的一个 近似曲面(以下简称近似曲面)，则采用柱坐标系三重积分对V A以及V B进行计算可得：
Figure PCTCN2022111004-appb-000009
Figure PCTCN2022111004-appb-000010
其中，d len为皱纹节距；d OD为皱纹护套内侧最小半径；d O’B为含绝缘屏蔽电缆的第二外侧半径；d O’C为含缓冲层电缆的第一外侧半径；d OC为原点O到C点的距离；θ A为皱纹护套与缓冲层接触的临界点A点处的角度。
在被积函数方面，可应用多项式插值、三角插值等方法对皱纹护套内侧曲线DE进行近似。在确定插值方法之后，可以确定插值基点，对现场电缆或供应商提供同型号同批次电缆在不同皱纹内的插值基点多点实测，取平均值之后可得到插值数据点的坐标(ρ k，0，z k)，k＝1,…,r；r为所选定插值方法所需插值数据点的个数。由此得到近似曲面在
Figure PCTCN2022111004-appb-000011
区间内的插值函数表达式为f(ρ)。
在积分上下限方面，易知，在θ＝0方向上，BD两点之间距离有最小值，为缓冲层在重力作用下被挤压最薄点厚度，记为d BB’。可以发现有：
d OO′＝d OA-d O′B-d BB′
其中，d OO’为皱纹护套的圆心与待测电缆线芯的圆心之间的距离；d O’B为含绝缘屏蔽电缆的第二外侧半径。
根据余弦定理可以发现：
Figure PCTCN2022111004-appb-000012
由于d OC>0，经过推导可得：
Figure PCTCN2022111004-appb-000013
显然上式在0≤θ P≤θ A区间均成立。记d OA为皱纹护套的内侧半径，显然有d OD＝d OA。
可以发现，当电缆上方皱纹护套与缓冲层之间未接触的情况下，如图3所示，即d BB’+d O‘B+d O’C≤2d OA 时，在皱纹护套与缓冲层接触临界点A处有：
Figure PCTCN2022111004-appb-000014
显然，当电缆上方皱纹护套与缓冲层之间存在接触的情况下，如图4所示，即d BB’+d O’B+d O‘C>2d OA时，有θ A＝π。则可得单个皱纹节距内缓冲层受压形变比率为：
Figure PCTCN2022111004-appb-000015
需要说明的是，在确定具体插值函数之后，可对上式二重积分进行化简尝试得到单变量定积分表达式。可以发现上述化简前后的积分均不能保证具备解析解，可应用数值积分方法求解。梯形法、辛普森法则、牛顿-柯特斯公式、龙贝格方法、高斯积分法、切比雪夫积分法以及蒙特卡罗积分法等数值积分法及其改进形式均可用于求取上述积分，从而得到单个皱纹节距内缓冲层受压形变比率的近似值，进而得到整缆缓冲层受压形变比率的近似值。
在又一个优选实施例中，所述S5，获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离，具体包括：
S51，在体积电阻率检测装置的上、下电极之间放入抽出空气但不含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触，获取此时上、下电极之间的距离，作为初始电极距离；
S52，在体积电阻率检测装置的上、下电极之间放入抽出空气且含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触；
S53，控制上电极以第二速度缓慢下降，直至达到所述缓冲层的受压形变比率；其中，所述第二速度小于所述第一速度；
S54，逐步升高所述上、下电极之间的直流电压，直至电流达到通路电流阈值，并维持预设时间；
S55，获取所述预设时间后的上、下电极之间的电压、电流、电极面积以及所述上、下电极之间的电极距离。
具体地，在体积电阻率检测装置上下两电极之间放入抽出空气但不含缓冲层的电极包装，并选择体积电阻率检测装置“归零”功能，检测装置上下电极之间开始施加低压直流电压，通过传动机构控制上电极缓慢下降。当电流计读数超过短路阈值ε sc时，认为上下电极已与电极包装充分接触，位置传感器读取两电极之间距离，作为初始电极距离d 1。停止施加上下电极之间的电压，传动机构控制体积电阻率检测装置上电极缓慢上升至起始位置。
对电缆外护套以及皱纹护套进行拆解，将绕包搭盖的缓冲层快速切割为合适的尺寸，并放入电极包装 中。缓冲层需要保持电缆中绕包搭盖的初始状态，并且表面能够覆盖电极包装两侧的导体电极。对电极包装进行密封后，抽出包装中的空气进行密封保存，作为封装后的缓冲层试样。封装后的缓冲层由于抽真空状态，一方面可以保持绕包搭盖的状态，不会发生松动脱落；另一方面可以防止存放过程中缓冲层受潮。
在体积电阻率检测装置上下两电极之间放入待测的封装后的缓冲层试样，并选择体积电阻率检测装置“测量”功能，检测装置上下电极之间施加低压直流电压，通过传动机构控制上电极缓慢下降。当临近时刻取样的两个电流测量值I 1与I 2的相对误差小于通路阈值εloop，即
Figure PCTCN2022111004-appb-000016
时，可认为电极与封装后的缓冲层试样已充分接触，位置传感器读取两电极之间距离d 2。传动机构控制上电极以更慢的速度缓慢下降，传感器连续读取两电极之间距离d c，当缓冲层受压形变比率到达η时，传动机构使上电极保持静止，此时有
Figure PCTCN2022111004-appb-000017
即d c＝(1-η)(d 2-d 1)+d 1时，上电极保持静止。逐步升高上下两电极之间的直流电压，直到电流计检测到的电流I达到通路电流阈值I valid，即满足I>I valid时保持直流电压不变，并保持时间t秒，以剔除充电电流影响。获取t秒后的上下电极之间的电压U、电流I、电极面积S以及上、下电极之间的电极距离d。
在又一个优选实施例中，所述缓冲层的体积电阻率的计算公式为：
Figure PCTCN2022111004-appb-000018
其中，σ表示所述缓冲层的体积电阻率；η表示所述缓冲层的受压形变比率；U表示上下电极之间的电压；S表示电极面积；I表示电流；d 1表示初始电极距离；d 2表示电极距离。
在又一个优选实施例中，所述S7，将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果，具体包括：
S71，当所述体积电阻率小于或等于所述评价参数时，判定所述缓冲层不存在缺陷；
S72，当所述体积电阻率大于所述评价参数时，判定所述缓冲层存在缺陷。
具体地，将计算得到的体积电阻率与预设的评价参数进行比对，当体积电阻率小于或等于评价参数时，判定缓冲层不存在缺陷；当体积电阻率大于评价参数时，判定所述缓冲层存在缺陷。
下面以具体实施例对本发明所提供的电缆缓冲层的缺陷检测方法进行说明。
样例一：
对220kV高压电力电缆缓冲层体积电阻率进行检测，按照如下步骤进行：
S1，根据电缆出厂试验报告或实测结果，整理得到以下数据：皱纹护套内侧半径d OA标称值，含缓冲层电缆的第一外侧半径d O’C标称值，含绝缘屏蔽电缆的第二外侧半径d O’B标称值，含绝缘屏蔽电缆的第二外侧半径d O’B标称值，皱纹深度d dep标称值，缓冲层最薄点厚度d BB’。数据整理如表1：
表1 电缆皱纹护套的规格参数
变量 d OA d O’C d O’B d len d dep d BB’
数值(mm) 60.0 63.2 57.2 28 5.6 2.0
S2，根据含缓冲层电缆的第一外侧半径d O’C标称值、含绝缘屏蔽电缆的第二外侧半径d O’B标称值和含绝缘屏蔽电缆的第二外侧半径d O’B标称值，计算得到缓冲层未发生形变时的第一体积
Figure PCTCN2022111004-appb-000019
S3，选择插值方法、数值积分方法，得到插值基点ρ k，k＝1,…,r，r为插值方法所需插值数据点的个数。对全部k＝1,…,r，在所关注电缆或供应商提供同型号同批次电缆上，在不同皱纹内插值基点ρ k位置处多点测量皱纹内侧Z方向坐标，取平均值后可得到插值数据点的坐标(ρ k，0，z k)。测量后插值数据点坐标如表2：
表2 插值数据点坐标
插值点1 插值点2 插值点3 插值点4
(0.0600，0，0) (0.0619，0，0.0059) (0.0637，0，0.0089) (0.0656，0，0.0140)
依据插值数据点(ρ k，0，z k)，k＝1,…,r，进行插值计算，得到插值函数表达式f(ρ)。
三次多项式插值f(ρ)＝T 3ρ 3+T 2ρ 2+T 1ρ+T 0方程参数的计算结果如表3：
表3 插值函数的参数取值
T 3 T 2 T 1 T 0
128120 -24195 1524.56 -32.04
根据d OO′＝d OA-d O′B-d BB′计算圆心距离d OO’＝0.8mm。
判断d BB’+d O‘B+d O’C≤2d OA是否成立。若成立，则电缆上方皱纹护套与缓冲层未接触，皱纹护套与缓冲层接触临界点角度
Figure PCTCN2022111004-appb-000020
若不成立，则电缆上方皱纹护套与缓冲层有效接触，θ A＝π。
根据θ A、圆心距离d OO’、皱纹护套内侧半径d OA标称值，计算得到缓冲层受力发生形变时变形部分的第二体积
Figure PCTCN2022111004-appb-000021
S4，根据第一体积V A和第二体积V B计算得到缓冲层的受压形变比率
Figure PCTCN2022111004-appb-000022
对缓冲层受压形变比率η二重积分进行化简，之后应用数值积分方法，计算可得：η＝19.57％。
S5，确定短路阈值ε sc，通路阈值εloop，通路电流阈值I valid，充电电流时间t等阈值参数。阈值参数整理如表4：
表4 阈值参数
参数 ε sc(A) εloop(A) I valid(A) t(s)
数值 1 0.01 0.1 30
在体积电阻率检测装置上下两电极之间放入抽出空气但不含缓冲层的电极包装，并选择体积电阻率检测装置“归零”功能，检测装置上下电极之间开始施加低压直流电压，通过传动机构控制上电极缓慢下降。当电流计读数超过短路阈值ε sc时，认为上下电极已与电极包装充分接触，位置传感器读取两电极之间距离，作为初始电极距离d 1。停止施加上下电极之间的电压，传动机构控制体积电阻率检测装置上电极缓慢上升至起始位置。
对电缆外护套以及皱纹护套进行拆解，将绕包搭盖的缓冲层快速切割为合适的尺寸，并放入电极包装中。缓冲层需要保持电缆中绕包搭盖的初始状态，并且表面能够覆盖电极包装两侧的导体电极。对电极包装进行密封后，抽出包装中的空气进行密封保存，作为封装后的缓冲层试样。封装后的缓冲层由于抽真空状态，一方面可以保持绕包搭盖的状态，不会发生松动脱落；另一方面可以防止存放过程中缓冲层受潮。
在体积电阻率检测装置上下两电极之间放入待测的封装后的缓冲层试样，并选择体积电阻率检测装置“测量”功能，检测装置上下电极之间施加低压直流电压，通过传动机构控制上电极缓慢下降。当临近时刻取样的两个电流测量值I 1与I 2的相对误差小于通路阈值εloop，即
Figure PCTCN2022111004-appb-000023
时，可认为电极与封装后的缓冲层试样已充分接触，位置传感器读取两电极之间距离d 2。传动机构控制上电极以更慢的速度缓慢下降，传感器连续读取两电极之间距离d c，当缓冲层受压形变比率到达η时，传动机构使上电极保持静 止，此时有
Figure PCTCN2022111004-appb-000024
即d c＝(1-η)(d 2-d 1)+d 1时，上电极保持静止。逐步升高上下两电极之间的直流电压，直到电流计检测到的电流I达到通路电流阈值I valid，即满足I>I valid时保持直流电压不变，并保持时间t秒，以剔除充电电流影响。获取t秒后的上下电极之间的电压U、电流I以及电极面积S。
S6，根据上下电极之间的电压U、电流I、电极面积S、缓冲层受压形变比率到达η以及位置传感器读取两电极之间距离d 1、d 2计算得到缓冲层的体积电阻率
Figure PCTCN2022111004-appb-000025
计算参数整理如表5：
表5 计算参数
结果 U(V) I(A) S(m 2) d(m) d 1(m) σ(Ω·m)
数值 22.19 0.082 0.001963 0.00514 0.00031 110.11
S7，依据相应的标准给出体积电阻率是否合格的结论。
目前JB/T 10259-2014《电缆和光缆用阻水带》中对体积电阻率的要求是不超过1000Ω·m，所以该电缆缓冲层的体积电阻率合格，则该电缆缓冲层不存在质量缺陷。
相应地，本发明还提供一种电缆缓冲层的缺陷检测装置，能够实现上述实施例中的电缆缓冲层的缺陷检测方法的所有流程。
请参阅图6，图6是本发明提供的一种电缆缓冲层的缺陷检测装置的一个优选实施例的结构示意图。所述电缆缓冲层的缺陷检测装置，包括：
第一获取模块601，用于获取待测电缆皱纹护套的规格参数；其中，所述规格参数包括皱纹护套的内侧半径、含缓冲层的所述待测电缆的第一外侧半径、含屏蔽层的所述待测电缆的第二外侧半径、皱纹节距、皱纹深度和缓冲层的最薄点厚度；
第一体积计算模块602，用于根据所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述皱纹节距，计算得到所述缓冲层未发生形变时的第一体积；
第二体积计算模块603，用于根据所述皱纹护套的内侧半径、所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述缓冲层的最薄点厚度，计算得到所述缓冲层受力发生形变时变形部分的第二体积；
受压形变比率计算模块604，用于根据所述第一体积和所述第二体积计算得到所述缓冲层的受压形变比率；
第二获取模块605，用于获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；
体积电阻率计算模块606，用于根据所述电压、所述电流、所述电极面积、所述电极距离以及所述初始 电极距离，计算得到所述缓冲层的体积电阻率；
缺陷检测模块607，用于将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果。
优选地，所述缓冲层的受压形变比率的计算公式为：
Figure PCTCN2022111004-appb-000026
其中，η表示所述缓冲层的受压形变比率；V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积。
优选地，所述缓冲层未发生形变时的第一体积的计算公式为：
Figure PCTCN2022111004-appb-000027
其中，V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d len表示所述皱纹节距；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径。
优选地，所述缓冲层受力发生形变时变形部分的第二体积的计算公式为：
Figure PCTCN2022111004-appb-000028
其中，V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d OA表示所述皱纹护套的内侧半径；f(ρ)表示插值函数；d OO’表示所述皱纹护套的圆心与所述待测电缆线芯的圆心之间的距离，且d OO′＝d OA-d O′B-d BB′，d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径，d BB’表示所述缓冲层的最薄点厚度。
优选地，第二获取模块605，具体用于：
在体积电阻率检测装置的上、下电极之间放入抽出空气但不含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触，获取此时上、下电极之间的距离，作为初始电极距离；
在体积电阻率检测装置的上、下电极之间放入抽出空气且含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触；
控制上电极以第二速度缓慢下降，直至达到所述缓冲层的受压形变比率；其中，所述第二速度小于所述第一速度；
逐步升高所述上、下电极之间的直流电压，直至电流达到通路电流阈值，并维持预设时间；
获取所述预设时间后的上、下电极之间的电压、电流、电极面积以及所述上、下电极之间的电极距离。
优选地，所述缓冲层的体积电阻率的计算公式为：
Figure PCTCN2022111004-appb-000029
其中，σ表示所述缓冲层的体积电阻率；η表示所述缓冲层的受压形变比率；U表示上下电极之间的电压；S表示电极面积；I表示电流；d 1表示初始电极距离；d 2表示电极距离。
优选地，所缺陷检测模块607，具体用于：
当所述体积电阻率小于或等于所述评价参数时，判定所述缓冲层不存在缺陷；
当所述体积电阻率大于所述评价参数时，判定所述缓冲层存在缺陷。
在具体实施当中，本发明实施例提供的电缆缓冲层的缺陷检测装置的工作原理、控制流程及实现的技术效果，与上述实施例中的电缆缓冲层的缺陷检测方法对应相同，在此不再赘述。
在另一个实施示例中，电缆缓冲层的缺陷检测装置包括：处理器，其中所述处理器用于执行存在存储器的上述程序模块，包括：第一获取模块601、第一体积计算模块602、第二体积计算模块603、受压形变比率计算模块604、第二获取模块605、体积电阻率计算模块606和缺陷检测模块607。
请参阅图7，图7是本发明提供的一种终端设备的一个优选实施例的结构示意图。所述终端设备包括处理器701、存储器702以及存储在所述存储器702中且被配置为由所述处理器701执行的计算机程序，所述处理器701执行所述计算机程序时实现上述任一实施例所述的电缆缓冲层的缺陷检测方法。
优选地，所述计算机程序可以被分割成一个或多个模块/单元(如计算机程序1、计算机程序2、……)，所述一个或者多个模块/单元被存储在所述存储器702中，并由所述处理器701执行，以完成本发明。所述一个或多个模块/单元可以是能够完成特定功能的一系列计算机程序指令段，该指令段用于描述所述计算机程序在所述终端设备中的执行过程。
所述处理器701可以是中央处理单元(Central Processing Unit，CPU)，还可以是其他通用处理器、数字信号处理器(Digital Signal Processor，DSP)、专用集成电路(Application Specific Integrated Circuit，ASIC)、现场可编程门阵列(Field-Programmable Gate Array，FPGA)或者其他可编程逻辑器件、分立门或者晶体管逻辑器件、分立硬件组件等，通用处理器可以是微处理器，或者所述处理器701也可以是任何常规的处理器，所述处理器701是所述终端设备的控制中心，利用各种接口和线路连接所述终端设备的各个部分。
所述存储器702主要包括程序存储区和数据存储区，其中，程序存储区可存储操作系统、至少一个功能所需的应用程序等，数据存储区可存储相关数据等。此外，所述存储器702可以是高速随机存取存储器，还可以是非易失性存储器，例如插接式硬盘，智能存储卡(Smart Media Card，SMC)、安全数字(Secure Digital，SD)卡和闪存卡(Flash Card)等，或所述存储器702也可以是其他易失性固态存储器件。
需要说明的是，上述终端设备可包括，但不仅限于，处理器、存储器，本领域技术人员可以理解，图7的结构示意图仅仅是上述终端设备的示例，并不构成对上述终端设备的限定，可以包括比图示更多或更少的部件，或者组合某些部件，或者不同的部件。
本发明实施例还提供了一种计算机可读存储介质，所述计算机可读存储介质包括存储的计算机程序，其中，在所述计算机程序运行时控制所述计算机可读存储介质所在设备执行上述任一实施例所述的电缆缓冲层的缺陷检测方法。
本发明实施例提供了一种电缆缓冲层的缺陷检测方法、装置、设备及存储介质，通过获取待测电缆皱纹护套的规格参数，计算得到电缆缓冲层未发生形变时的第一体积和电缆缓冲层受力发生形变时变形部分的第二体积，以得到缓冲层的受压形变比率，再获取缓冲层在达到受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离，计算得到缓冲层的体积电阻率，将体积电阻率与预设的评价参数进行比对，得到缓冲层的缺陷检测结果。本发明实施例考虑电缆缓冲层绕包带的搭盖、受潮和受压情况，能够准确计算出电缆缓冲层的体积电阻率，进而可以根据体积电阻率准确判断电缆缓冲层是否存在烧蚀缺陷。
需说明的是，以上所描述的装置实施例仅仅是示意性的，其中所述作为分离部件说明的单元可以是或者也可以不是物理上分开的，作为单元显示的部件可以是或者也可以不是物理单元，即可以位于一个地方，或者也可以分布到多个网络单元上。可以根据实际的需要选择其中的部分或者全部模块来实现本实施例方案的目的。另外，本发明提供的系统实施例附图中，模块之间的连接关系表示它们之间具有通信连接，具体可以实现为一条或多条通信总线或信号线。本领域普通技术人员在不付出创造性劳动的情况下，即可以理解并实施。
以上所述是本发明的优选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本发明原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也视为本发明的保护范围。

Claims (10)

  1. 一种电缆缓冲层的缺陷检测方法，其特征在于，包括：
    获取待测电缆皱纹护套的规格参数；其中，所述规格参数包括皱纹护套的内侧半径、含缓冲层的所述待测电缆的第一外侧半径、含屏蔽层的所述待测电缆的第二外侧半径、皱纹节距、皱纹深度和缓冲层的最薄点厚度；
    根据所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述皱纹节距，计算得到所述缓冲层未发生形变时的第一体积；
    根据所述皱纹护套的内侧半径、所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述缓冲层的最薄点厚度，计算得到所述缓冲层受力发生形变时变形部分的第二体积；
    根据所述第一体积和所述第二体积计算得到所述缓冲层的受压形变比率；
    获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；
    根据所述电压、所述电流、所述电极面积、所述电极距离以及所述初始电极距离，计算得到所述缓冲层的体积电阻率；
    将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果。
  2. 如权利要求1所述的电缆缓冲层的缺陷检测方法，其特征在于，所述缓冲层的受压形变比率的计算公式为：
    Figure PCTCN2022111004-appb-100001
    其中，η表示所述缓冲层的受压形变比率；V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积。
  3. 如权利要求2所述的电缆缓冲层的缺陷检测方法，其特征在于，所述缓冲层未发生形变时的第一体积的计算公式为：
    Figure PCTCN2022111004-appb-100002
    其中，V A表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层未发生形变时的第一体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d len表示所述皱纹节距；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径。
  4. 如权利要求3所述的电缆缓冲层的缺陷检测方法，其特征在于，所述缓冲层受力发生形变时变形部 分的第二体积的计算公式为：
    Figure PCTCN2022111004-appb-100003
    其中，V B表示在绝缘屏蔽与皱纹护套之间起导电作用部分的所述缓冲层受力发生形变时变形部分的第二体积；θ A表示所述皱纹护套与所述缓冲层的接触临界点的角度；d O’C表示所述含缓冲层的所述待测电缆的第一外侧半径；d OA表示所述皱纹护套的内侧半径；f(ρ)表示插值函数；d OO’表示所述皱纹护套的圆心与所述待测电缆线芯的圆心之间的距离，且d OO′＝d OA-d O′B-d BB′，d O’B表示所述含屏蔽层的所述待测电缆的第二外侧半径，d BB’表示所述缓冲层的最薄点厚度。
  5. 如权利要求1所述的电缆缓冲层的缺陷检测方法，其特征在于，所述获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离，具体包括：
    在体积电阻率检测装置的上、下电极之间放入抽出空气但不含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触，获取此时上、下电极之间的距离，作为初始电极距离；
    在体积电阻率检测装置的上、下电极之间放入抽出空气且含所述缓冲层的电极包装，并施加低压直流电压，控制上电极以第一速度缓慢下降，直至上、下电极与电极包装充分接触；
    控制上电极以第二速度缓慢下降，直至达到所述缓冲层的受压形变比率；其中，所述第二速度小于所述第一速度；
    逐步升高所述上、下电极之间的直流电压，直至电流达到通路电流阈值，并维持预设时间；
    获取所述预设时间后的上、下电极之间的电压、电流、电极面积以及所述上、下电极之间的电极距离。
  6. 如权利要求1所述的电缆缓冲层的缺陷检测方法，其特征在于，所述缓冲层的体积电阻率的计算公式为：
    Figure PCTCN2022111004-appb-100004
    其中，σ表示所述缓冲层的体积电阻率；η表示所述缓冲层的受压形变比率；U表示上下电极之间的电压；S表示电极面积；I表示电流；d 1表示初始电极距离；d 2表示电极距离。
  7. 如权利要求1所述的电缆缓冲层的缺陷检测方法，其特征在于，所述将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果，具体包括：
    当所述体积电阻率小于或等于所述评价参数时，判定所述缓冲层不存在缺陷；
    当所述体积电阻率大于所述评价参数时，判定所述缓冲层存在缺陷。
  8. 一种电缆缓冲层的缺陷检测装置，其特征在于，包括：
    第一获取模块，用于获取待测电缆皱纹护套的规格参数；其中，所述规格参数包括皱纹护套的内侧半径、含缓冲层的所述待测电缆的第一外侧半径、含屏蔽层的所述待测电缆的第二外侧半径、皱纹节距、皱纹深度和缓冲层的最薄点厚度；
    第一体积计算模块，用于根据所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述皱纹节距，计算得到所述缓冲层未发生形变时的第一体积；
    第二体积计算模块，用于根据所述皱纹护套的内侧半径、所述含缓冲层的所述待测电缆的第一外侧半径、所述含屏蔽层的所述待测电缆的第二外侧半径和所述缓冲层的最薄点厚度，计算得到所述缓冲层受力发生形变时变形部分的第二体积；
    受压形变比率计算模块，用于根据所述第一体积和所述第二体积计算得到所述缓冲层的受压形变比率；
    第二获取模块，用于获取所述缓冲层在达到所述受压形变比率时的电压、电流、电极面积、电极距离以及初始电极距离；
    体积电阻率计算模块，用于根据所述电压、所述电流、所述电极面积、所述电极距离以及所述初始电极距离，计算得到所述缓冲层的体积电阻率；
    缺陷检测模块，用于将所述体积电阻率与预设的评价参数进行比对，以得到所述缓冲层的缺陷检测结果。
  9. 一种终端设备，其特征在于，包括处理器、存储器以及存储在所述存储器中且被配置为由所述处理器执行的计算机程序，所述处理器执行所述计算机程序时实现如权利要求1至7中任意一项所述的电缆缓冲层的缺陷检测方法。
  10. 一种计算机可读存储介质，其特征在于，所述计算机可读存储介质包括存储的计算机程序，其中，在所述计算机程序运行时控制所述计算机可读存储介质所在设备执行如权利要求1至7中任意一项所述的电缆缓冲层的缺陷检测方法。
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