A cable defect detection apparatus, method, device and readable storage medium

Abstract

The application discloses a kind of cable defect detection equipment, method, device and readable storage medium, applied to cable detection field, comprising: light source, double optical fiber, acousto-optic sensor, photoelectric converter and electric signal processor;Double optical fiber includes the main optical fiber and slave optical fiber with light source connection in input end, and main optical fiber and slave optical fiber all receive standard light signal emitted by light source;Main optical fiber is connected with the cable to be measured by acousto-optic sensor, and acousto-optic sensor receives the ultrasonic signal generated by partial discharge of the cable to be measured, couples ultrasonic signal, and after coupling ultrasonic signal is transmitted to main optical fiber;Coupling ultrasonic signal and standard light signal occur acousto-optic effect in main optical fiber, and form the light signal to be measured;The output end of main optical fiber and the output end of slave optical fiber are all connected with electric signal processor by photoelectric converter.The application obtains the light signal to be measured not by acousto-optic sensor It is not interfered with electromagnetic interference, and electromagnetic interference is eliminated when cable is detected using photoelectric converter conversion.

Description

Technical Field

[0001] This invention relates to the field of cable inspection, and in particular to a cable defect inspection device, method, apparatus, and readable storage medium. Background Technology

[0002] Currently, partial discharge detection in power cable systems primarily relies on electrical methods, specifically electromagnetic coupling based on electrical signals to couple discharges caused by insulation degradation into the monitoring system. Sensors used include capacitive, inductive, UHF, and directional coupling types. However, electromagnetic coupling methods are susceptible to significant on-site electromagnetic interference. To avoid this interference, mainstream methods set the measurement signal frequency in the high-frequency band of 3MHz to 30MHz, or even the UHF band of 300MHz to 3GHz. However, regardless of the filtering techniques employed, hardware-based interference elimination is impossible, and software-assisted interference reduction methods often fail to confirm whether the truly early "low" or "weak" signals of partial discharge have been removed. This makes partial discharge identification extremely complex, and the electromagnetic signal after partial discharge detection is often submerged in environmental noise, leading to misinterpretations and significantly reducing the accuracy and sensitivity of partial discharge detection in high-voltage cable systems, easily resulting in false positives.

[0003] Therefore, how to minimize interference at the testing site and improve the accuracy of cable defect detection is a technical problem that needs to be solved by those skilled in the art. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a cable defect detection device, method, apparatus and readable storage medium, which solves the technical problems of low efficiency and low accuracy of cable defect detection in the prior art.

[0005] To solve the above-mentioned technical problems, the present invention provides a cable defect detection device, comprising:

[0006] Light source, dual optical fibers, acousto-optic sensor, photoelectric converter, and electrical signal processor;

[0007] The dual optical fibers include a main optical fiber and a slave optical fiber, both of which are connected to the light source at their input ends. Both the main optical fiber and the slave optical fiber receive standard optical signals emitted by the light source.

[0008] The main optical fiber is connected to the cable under test via the acousto-optic sensor. After receiving the ultrasonic signal generated by the partial discharge of the cable under test, the acousto-optic sensor couples the ultrasonic signal to obtain a coupled ultrasonic signal and transmits the coupled ultrasonic signal to the main optical fiber. The coupled ultrasonic signal and the standard optical signal undergo an acousto-optic effect in the main optical fiber to form the optical signal under test.

[0009] Both the output end of the main optical fiber and the output end of the slave optical fiber are connected to the electrical signal processor through the photoelectric converter.

[0010] Optionally, the acousto-optic sensor includes:

[0011] An ultrasonic coupling medium and an acousto-optic medium, wherein the ultrasonic coupling medium is located on the outer surface of the acousto-optic medium.

[0012] Optionally, the acousto-optic sensor further includes:

[0013] A sound-absorbing device is disposed on the first outer surface of the acousto-optic medium, and an ultrasonic coupling medium is disposed on the second outer surface of the acousto-optic medium, with the first outer surface and the second outer surface being disposed opposite to each other.

[0014] Optionally, the main optical fiber exits from the acousto-optic medium.

[0015] Optionally, the acoustic-optical sensor is mounted on the surface of the extruded layer of the cable body under test in an adhesive manner.

[0016] Optionally, the cable defect detection equipment further includes:

[0017] A differential signal processor, wherein the input terminal of the differential signal processor is connected to the photoelectric converter; and the output terminal of the differential signal processor is connected to the electrical signal processor.

[0018] The present invention also provides a cable defect detection method, applied to the aforementioned cable defect detection equipment, the method comprising:

[0019] Acquire the electrical signal to be tested and the interference electrical signal; the electrical signal to be tested is the electrical signal converted from the optical signal to be tested in the main optical fiber by the photoelectric converter, and the interference electrical signal is the electrical signal converted from the standard optical signal in the secondary optical fiber by the photoelectric converter; the optical signal to be tested is the optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber.

[0020] Based on the electrical signal to be tested and the interference electrical signal, determine whether the cable to be tested has a defect.

[0021] Optionally, determining whether the cable under test has a defect based on the electrical signal to be tested and the interference electrical signal includes:

[0022] The differential calculation is performed on the electrical signal under test and the interference electrical signal to obtain the differential value;

[0023] Obtain a preset defect difference threshold, and compare the relationship between the difference value and the preset defect difference threshold;

[0024] When the difference value is less than the preset defect difference threshold, it is determined that the cable to be tested has no defects;

[0025] When the difference value is greater than or equal to the preset defect difference threshold, it is determined that the cable to be tested has a defect.

[0026] The present invention also provides a cable defect detection device, comprising:

[0027] An electrical signal acquisition module is used to acquire the electrical signal to be tested and the interference electrical signal; the electrical signal to be tested is the electrical signal converted from the optical signal to be tested in the main optical fiber by the photoelectric converter, and the interference electrical signal is the electrical signal converted from the standard optical signal in the secondary optical fiber by the photoelectric converter; the optical signal to be tested is the optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber.

[0028] The defect determination module is used to determine whether there is a defect in the cable under test based on the electrical signal to be tested and the interference electrical signal.

[0029] The present invention also provides a readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described cable defect detection method.

[0030] As can be seen, the cable defect detection equipment provided by the present invention includes a light source, dual optical fibers, an acousto-optic sensor, a photoelectric converter, and an electrical signal processor. The dual optical fibers include a main optical fiber and a slave optical fiber, both of which are connected to the light source at their input ends. Both the main optical fiber and the slave optical fiber receive standard optical signals emitted by the light source. The main optical fiber is connected to the cable under test through the acousto-optic sensor. After receiving the ultrasonic signal generated by partial discharge of the cable under test, the acousto-optic sensor couples the ultrasonic signal to obtain a coupled ultrasonic signal and transmits the coupled ultrasonic signal to the main optical fiber. The coupled ultrasonic signal and the standard optical signal undergo an acousto-optic effect in the main optical fiber to form the optical signal under test. The output ends of the main optical fiber and the slave optical fiber are both connected to the electrical signal processor through the photoelectric converter. This invention utilizes a main optical fiber combined with an acousto-optic sensor to convert ultrasonic signals, including defect and interference signals, generated by partial discharge in the cable under test into a test optical signal. It also utilizes a secondary optical fiber to collect interference signals. A photoelectric converter then converts the test optical signal and interference signal collected from the main and secondary optical fibers respectively. Finally, an electrical signal processor identifies the converted electrical signal and performs defect detection. Compared to existing technologies that use electromagnetic coupling based on electrical signals to couple discharge signals generated by insulation degradation to the observation system for cable defect detection, the cable defect detection device provided by this invention, because it detects ultrasonic waves, is unaffected by electromagnetic interference and possesses inherently superior anti-interference performance. The detected signal originates from ultrasonic waves generated during partial discharge. Therefore, this device is unaffected by electromagnetic interference and has excellent anti-interference performance. Furthermore, since this method does not require damaging the cable insulation system structure, and the attenuation intensity of ultrasonic waves varies in other materials, signal sources outside the cable system can be largely excluded, further improving the effectiveness and accuracy of ultrasonic detection results.

[0031] In addition, the present invention also provides a cable defect detection method, apparatus and readable storage medium method, which also have the above-mentioned beneficial effects. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0033] Figure 1 This is a schematic diagram of the structure of a cable defect detection device provided in an embodiment of the present invention;

[0034] Figure 2This is a schematic diagram of a specific acoustic-optical sensor and main optical fiber connection device provided in an embodiment of the present invention;

[0035] Figure 3 This is a schematic diagram of a specific acoustic-optical sensor and a cable under test connection device provided in an embodiment of the present invention;

[0036] Figure 4 A flowchart of a cable defect detection method provided in an embodiment of the present invention;

[0037] Figure 5 This is a schematic diagram of the structure of a cable defect detection device provided in an embodiment of the present invention;

[0038] Appendix Figure 1-3 The reference numerals in the attached figures are explained as follows:

[0039] 10-Light source;

[0040] 20 - Dual optical fibers, 21 - Main optical fiber, 22 - Slave optical fiber;

[0041] 30-Acoustic-optic sensor; 31-Ultrasonic coupling medium; 32-Acoustic-optic medium; 33-Sound absorption device;

[0042] 40 - Photoelectric converter, 41 - First photoelectric converter, 42 - Second photoelectric converter;

[0043] 50 - Electrical signal processor; 51 - Differential signal processor;

[0044] 60 - Cable under test; 61 - Intermediate joint of the cable under test system;

[0045] 70 - Intermediate joint of the cable to be tested. Detailed Implementation

[0046] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] Example 1:

[0048] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a cable testing device provided in an embodiment of the present invention. The device may include:

[0049] Light source 10, dual optical fibers 20, acoustic-optical sensor 30, photoelectric converter 40, and electrical signal processor 50;

[0050] The dual optical fiber 20 includes a main optical fiber 21 and a slave optical fiber 22, both of which are connected to the light source 10 at their input ends. Both the main optical fiber 21 and the slave optical fiber 22 receive the standard optical signal emitted by the light source 10.

[0051] The main optical fiber 21 is connected to the cable under test 60 through the acousto-optic sensor 30. After receiving the ultrasonic signal generated by the partial discharge of the cable under test 60, the acousto-optic sensor 30 couples the ultrasonic signal to obtain a coupled ultrasonic signal and transmits the coupled ultrasonic signal to the main optical fiber 21. The coupled ultrasonic signal and the standard optical signal undergo an acousto-optic effect in the main optical fiber 21 to form the optical signal under test.

[0052] Both the output end of the main optical fiber 21 and the output end of the slave optical fiber 22 are connected to the electrical signal processor 50 through the photoelectric converter 40.

[0053] This embodiment does not limit the specific type of the light source 10, as long as it can emit laser light to the dual optical fibers 20. For example, the light source 10 can be an argon ion laser source; or the light source 10 can be a semiconductor laser source; or the light source 10 can be a helium-neon laser source. This embodiment does not limit the specific type of the dual optical fibers 20, as long as it includes two optical fibers. For example, the dual optical fibers 20 can be multimode optical fibers; or the dual optical fibers 20 can be single-mode optical fibers. The acousto-optic sensor 30 in this embodiment can acquire the ultrasonic signal generated when the cable under test 60 is partially discharged, and can couple and modulate the ultrasonic signal to convert the ultrasonic signal into the optical signal under test. The photoelectric converter 40 in this embodiment, also known as a fiber optic transceiver, is a device similar to a baseband MODEM (digital modem). It is an Ethernet transmission media conversion unit that converts short-distance twisted-pair electrical signals and long-distance optical signals, and is also called a fiber converter in many places. This embodiment does not limit the interface type of the photoelectric converter 40, as long as it can work in conjunction with the cable under test 60 and the dual optical fibers 20. For example, the interface type of the photoelectric converter can be 1000Base-SX; or the interface type of the photoelectric converter 40 can be CX; the interface type of the photoelectric converter 40 can also be LHX; or the interface type of the photoelectric converter 40 can also be EX. This embodiment does not limit the specific connection method between the acoustic-optical sensor 30 and the cable under test 60. For example, the acoustic-optical sensor 30 is mounted on the surface of the local extruded layer of the cable under test 60; or the acoustic-optical sensor 30 is connected to the intermediate connector 61 of the subordinate cable system under test of the cable under test 60. It is understood that the electrical signal processor 50 in this embodiment can receive the electrical signal converted by the photoelectric converter 40 for cable defect detection, hence it is called an electrical signal processor.

[0054] This embodiment does not limit the fiber types of the main fiber 21 and the secondary fiber 22, as long as they are consistent with the optical type of the dual fiber 20. For example, the fiber types of the main fiber 21 and the secondary fiber 22 can be multimode fiber; or the fiber types of the main fiber 21 and the secondary fiber 22 can also be single-mode fiber. It is understood that the standard optical signal generated by the light source 10 can propagate in the main fiber 21 and the secondary fiber 22.

[0055] It should be noted that in this embodiment, the acousto-optic sensor 30 receives the ultrasonic signal generated by the partial discharge of the cable under test 60 and forms the optical signal to be tested. The process is as follows: after acquiring the collected ultrasonic signal, the coupling medium in the acousto-optic sensor couples the ultrasonic signal within a specific wavelength range. When the coupled ultrasonic signal passes through the main optical fiber 21, utilizing the "acoustic-optic effect" in physics, the coupled ultrasonic signal becomes a "grating." The frequency, phase angle, and amplitude of the standard optical signal after interference by the "grating" change compared to the original light. This phenomenon is used to convert the coupled ultrasonic signal into the optical signal to be tested. The optical signal to be tested continues to propagate along the main optical fiber and, together with the standard optical signal from the optical fiber 22, is received by the photoelectric sensor 40 and converted into an electrical signal. Because the frequency, phase, amplitude, etc., of the converted electrical signal are inconsistent with the information after the active light conversion, cable defect detection is achieved.

[0056] This embodiment does not limit the number of photoelectric converters 40 used when the output ends of the main optical fiber 21 and the output ends of the secondary optical fiber 22 are connected to the electrical signal processor 50 via photoelectric converters 40. For example, there may be one photoelectric converter 40, which can collect the optical signals transmitted from the main optical fiber 21 and the secondary optical fiber 22 respectively and transmit them sequentially to the electrical signal processor 50 so that the electrical signal processor can distinguish between the optical signals transmitted from the main optical fiber 21 and the secondary optical fiber 22. Alternatively, there may be two photoelectric converters 40, which receive the optical signals transmitted from the main optical fiber 21 and the secondary optical fiber 22 respectively.

[0057] Furthermore, in order to ensure that the ultrasonic signal can be converted into an optical signal, the aforementioned acousto-optic sensor 30 may include:

[0058] The ultrasonic coupling medium 31 and the acousto-optic medium 32 are located on the outer surface of the acousto-optic medium 32.

[0059] This embodiment does not limit the specific way in which the ultrasonic coupling medium 31 is disposed on the acousto-optic medium 32, as long as the ultrasonic coupling medium 31 can be located on the outer surface of the acousto-optic medium 32. For example, the ultrasonic coupling medium 31 and the acousto-optic medium 32 can be connected by a threaded connection; or the ultrasonic coupling medium 31 and the acousto-optic medium 32 can also be connected by welding. It should be noted that, in this embodiment, the ultrasonic coupling medium 31 being located on the outer surface of the acousto-optic medium 32 means that the ultrasonic signal generated by the partial discharge of the cable under test 60 first passes through the ultrasonic coupling medium 31 and then through the acousto-optic medium 32, hence the ultrasonic coupling medium 31 is located on the outer surface of the acousto-optic medium 32.

[0060] Furthermore, in order to "absorb" the ultrasonic signal propagating through the acousto-optic medium and minimize the propagation of the ultrasonic signal outside the main optical fiber, the aforementioned acousto-optic sensor 31 may further include:

[0061] The sound-absorbing device 33 is disposed on the first outer surface of the acoustic-optical medium 32, and the ultrasonic coupling medium 31 is disposed on the second outer surface of the acoustic-optical medium 32. The first outer surface and the second outer surface are disposed opposite to each other.

[0062] This embodiment does not limit the manner in which the sound-absorbing device 33 is disposed on the first outer surface of the acousto-optic medium 32. For example, the sound-absorbing device 33 may be disposed on the first outer surface of the acousto-optic medium 32 via a threaded connection; or it may be disposed on the first outer surface of the acousto-optic medium 32 via welding. It should be noted that the ultrasonic coupling medium 31, the acousto-optic medium 32, and the sound-absorbing device 33 can be connected in a sealed manner, and the ultrasonic coupling medium 31 and the sound-absorbing device 33 are disposed opposite each other on the outer surface of the acousto-optic medium 32. Because sealing the ultrasonic coupling medium 31, the acousto-optic medium 32, and the sound-absorbing device 33 to form the acousto-optic sensor 30 can reduce interference from the external environment. It is understood that the coupled ultrasonic signal propagating after passing through the acousto-optic medium 32 is "absorbed" to minimize the propagation of the ultrasonic signal outside the main optical fiber.

[0063] Furthermore, in order to obtain the corresponding optical signal to be tested based on the ultrasonic signal in the main optical fiber 21, the main optical fiber 21 extends out from the acousto-optic medium 32.

[0064] This embodiment does not limit the specific position where the main optical fiber 21 exits the acousto-optic medium 32, as long as the main optical fiber 21 can exit the acousto-optic medium 32. For example, the main optical fiber 21 can exit from one-third of the acousto-optic medium 32; or the main optical fiber 21 can exit from one-quarter of the acousto-optic medium 32; or the main optical fiber 21 can exit from three-fifths of the acousto-optic medium 32. It can be understood that, in order to prevent the main optical fiber 21 from being unable to exit the acousto-optic medium 32, the main optical fiber 21 can exit from one-half of the acousto-optic medium 32.

[0065] Please refer to the details. Figure 2 Please refer to Figure 2 , Figure 2 This is a schematic diagram of a specific acoustic-optical sensor and main optical fiber connection device provided in an embodiment of the present invention. Figure 2 It can be seen that the ultrasonic coupling medium 31, the acousto-optic medium 32 and the sound-absorbing device 33 together form the acousto-optic sensor 30, and the main optical fiber 21 passes through the acousto-optic medium 32 and is connected to the acousto-optic sensor 30.

[0066] Furthermore, in order not to affect the normal operation of the cable under test, the aforementioned acoustic and optical sensor 30 is attached to the surface of the extruded layer of the cable under test 60 body.

[0067] It should be noted that the origin of the extruded layer surface of the cable body is due to the fact that most XLPE power cables use a three-layer co-extrusion technology, which means that the conductor shielding layer, insulation layer, and insulation shielding layer of the cable are simultaneously extruded on an extruder and sequentially wrapped around the cable conductor. The cable is also called the "core" in the factory, but in actual use, cables also require additional layers beyond the "core" to protect the cable from damage in case of faults, a hydrophobic buffer layer (optional) to prevent impact damage or external waterproofing, a metal sheath layer (aluminum or lead sheath) for traction and laying and to protect the cable from external damage such as impacts, and an outer sheath layer. When installing cable accessories, all materials other than the core need to be stripped at the installation location to ensure a tight fit between the cable accessory insulation and the main cable insulation, forming a reliable insulation system.

[0068] Please refer to Figure 3 , Figure 3 This is a schematic diagram of a specific acoustic-optical sensor and a cable under test connection device provided in an embodiment of the present invention. Figure 3 It can be seen that the acoustic-optical sensor 30 and the surface of the extruded layer of the cable under test 60 are connected, and the intermediate joint 70 of the cable under test belongs to the cable under test 60.

[0069] Furthermore, to facilitate calculation, the aforementioned cable defect detection equipment also includes a differential signal processor 51, the input of which is connected to the photoelectric converter 40; the output of which is connected to the electrical signal processor 50.

[0070] It should be noted that in this embodiment, the differential signal processor 51 can perform differential calculations on the electrical signals sent by the photoelectric converter 40 and send the differential calculation results to the electrical signal processor 50 so that the electrical signal processor 50 can perform cable defect detection.

[0071] The cable defect detection equipment provided in this embodiment of the invention comprises a light source 10, dual optical fibers 20, an acousto-optic sensor 30, a photoelectric converter 40, and an electrical signal processor 50. The dual optical fibers 20 include a main optical fiber 21 and a secondary optical fiber 22, both of which have their input ends connected to the light source 10. Both the main optical fiber 21 and the secondary optical fiber 22 receive standard optical signals emitted by the light source 10. The main optical fiber 21 is connected to the cable under test 60 through the acousto-optic sensor 30. After receiving the ultrasonic signal generated by the partial discharge of the cable under test 60, the acousto-optic sensor 30 couples the ultrasonic signal to obtain a coupled ultrasonic signal and transmits the coupled ultrasonic signal to the main optical fiber 21. The coupled ultrasonic signal and the standard optical signal undergo an acousto-optic effect in the main optical fiber 21 to form the optical signal under test. The output ends of the main optical fiber 21 and the secondary optical fiber 22 are both connected to the electrical signal processor 50 through the photoelectric converter 40. As can be seen, compared with existing electromagnetic coupling methods based on electrical signals that couple discharge signals generated due to insulation degradation to the observation system for cable defect detection, the cable defect detection device provided by this invention, because it detects ultrasonic waves, is unaffected by electromagnetic interference and has naturally excellent anti-interference performance. The detected signal originates from ultrasonic waves generated during partial discharge. Therefore, this device is unaffected by electromagnetic interference and has excellent anti-interference performance. In addition, since this method does not require damaging the cable insulation system structure, and the attenuation intensity of ultrasonic waves is inconsistent in other materials, signal sources other than the cable system can be basically excluded, further improving the effectiveness and accuracy of ultrasonic detection results. Furthermore, the acousto-optic sensor 30 provided in this embodiment includes an ultrasonic coupling medium 31, an acousto-optic medium 32, and a sound-absorbing device 33, and the main optical fiber 21 passes through the acousto-optic medium 32 to convert ultrasonic signals into optical signals, making the collected optical signals more accurate; and the acousto-optic sensor is attached to the surface of the extruded layer of the cable body under test, so the acousto-optic sensor will not affect the normal operation of the cable under test.

[0072] The cable defect detection method provided in the embodiments of the present invention will be described below. The cable defect detection method described below is applied to the cable defect detection equipment described above and can be referred to in correspondence with the cable defect detection equipment described above.

[0073] Please refer to the details. Figure 4 , Figure 4 A flowchart of a cable defect detection method provided in an embodiment of the present invention may include:

[0074] S100, acquire the electrical signal to be tested and the interference electrical signal; the electrical signal to be tested is the electrical signal converted from the optical signal to be tested in the main optical fiber by the photoelectric converter, and the interference electrical signal is the electrical signal converted from the standard optical signal in the optical fiber by the photoelectric converter; the optical signal to be tested is the optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber.

[0075] In this embodiment, the electrical signal refers to voltage or current that changes over time. Therefore, mathematically, it can be represented as a function of time, and its waveform can be plotted. Since non-electrical physical quantities can be easily converted into electrical signals by various sensors, and electrical signals are easy to transmit and control, they are the most widely used signals. This embodiment does not limit the specific value of the electrical signal to be measured. For example, the electrical signal to be measured can be 2; or it can be 3; or it can be 4. This embodiment also does not limit the specific value of the interference signal, as long as the interference signal is less than the electrical signal to be measured. For example, if the electrical signal to be measured is 2, the interference signal can be 1; or if the electrical signal to be measured is 3, the interference signal is 2. It is understood that since only the interference signal is collected from the optical fiber, while the main optical fiber collects the sum of the interference signal and the defect signal of the signal to be measured, the signal to be measured is definitely greater than the interference signal.

[0076] S101, determine whether there is a defect in the cable under test based on the electrical signal to be tested and the interference electrical signal.

[0077] This embodiment does not limit the specific method for determining whether the cable under test has a defect based on the electrical signal under test and the interference signal. For example, a differential operation can be performed directly on the electrical signal under test and the interference signal. When the difference value is 0, it is determined that the cable under test has no defect; when the difference value is not 0, it is determined that the cable under test has a defect. Alternatively, a preset defect difference threshold can be obtained after performing the differential operation. When the difference value is less than the preset defect difference threshold, it is determined that the cable under test has no defect; when the difference value is greater than or equal to the preset defect difference threshold, it is determined that the cable under test has a defect. This embodiment does not limit the specific operations performed when determining that the cable under test has a defect. For example, the identification number corresponding to the acoustic-optical sensor can be obtained, and the defect location of the cable under test can be determined based on the identification number, directly locating the defect based on the identification number. Alternatively, this embodiment can also directly send a prompt message indicating that the cable under test has a defect.

[0078] Furthermore, in order to accurately determine whether the cable under test has defects, the above-mentioned method of determining whether the cable under test has defects based on the electrical signal under test and the interference electrical signal may include:

[0079] Synchronous differential calculation is performed between the electrical signal under test and the interference electrical signal to obtain the differential value;

[0080] Obtain the preset defect difference threshold and compare the difference value with the preset defect difference threshold;

[0081] When the difference value is less than the preset defect difference threshold, it is determined that the cable to be tested has no defects;

[0082] When the difference value is greater than or equal to the preset defect difference threshold, it is determined that the cable to be tested has a defect.

[0083] This embodiment calculates the difference value by synchronously performing differential calculations on the electrical signal under test and the interfering electrical signal. Then, it compares the difference value with a preset defect differential threshold to determine whether the cable under test has a defect. It is understood that, in addition to the interfering electrical signal collected from the optical fiber in this embodiment, other types of interference signals exist. To improve the accuracy of cable defect detection, the preset defect differential threshold can be set based on the difference value when the cable under test was previously found to have a defect, thereby enhancing the accuracy of cable defect detection.

[0084] The cable defect detection method provided in this invention acquires a test electrical signal and an interference electrical signal. The test electrical signal is an electrical signal converted from the test optical signal in the main optical fiber by a photoelectric converter, and the interference electrical signal is an electrical signal converted from the standard optical signal in the optical fiber by the photoelectric converter. The test optical signal is an optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber. Based on the test electrical signal and the interference electrical signal, it is determined whether the cable under test has a defect. Furthermore, since defect detection analysis can be performed based on a preset defect differential threshold, the accuracy of cable defect detection is higher.

[0085] The cable defect detection device provided in the embodiments of the present invention will be described below. The cable defect detection device described below is applied to the cable defect detection method described above and can be referred to in correspondence with the cable defect detection method described above.

[0086] Please refer to the details. Figure 5 , Figure 5 A flowchart of a cable defect detection device provided in an embodiment of the present invention may include:

[0087] The electrical signal acquisition module 100 is used to acquire the electrical signal to be tested and the interference electrical signal; the electrical signal to be tested is the electrical signal converted from the optical signal to be tested in the main optical fiber by the photoelectric converter, and the interference electrical signal is the electrical signal converted from the standard optical signal in the secondary optical fiber by the photoelectric converter; the optical signal to be tested is the optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber.

[0088] The defect determination module 200 is used to determine whether there is a defect in the cable under test based on the electrical signal to be tested and the interference electrical signal.

[0089] Furthermore, based on the above embodiments, the defect determination module 200 may include:

[0090] The differential value calculation unit is used to perform synchronous differential calculation on the electrical signal under test and the interference electrical signal to obtain the differential value;

[0091] A preset defect difference threshold determination unit is used to obtain a preset defect difference threshold and compare the relationship between the difference value and the preset defect difference threshold.

[0092] The cable under test is defect-free determination unit, which is used to determine that the cable under test is defect-free when the difference value is less than the preset defect difference threshold.

[0093] The cable under test defect determination unit is used to determine that the cable under test has a defect when the difference value is greater than or equal to the preset defect difference threshold.

[0094] The cable defect detection device provided in this embodiment of the invention uses an electrical signal acquisition module 100 to acquire a test electrical signal and an interference electrical signal. The test electrical signal is an electrical signal converted from the test optical signal in the main optical fiber by the photoelectric converter, and the interference electrical signal is an electrical signal converted from the standard optical signal in the secondary optical fiber by the photoelectric converter. The test optical signal is an optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber. The defect determination module 200 is used to determine whether there is a defect in the cable under test based on the test electrical signal and the interference electrical signal. Furthermore, since defect detection analysis can be performed based on a preset defect differential threshold, the accuracy of cable defect detection is higher.

[0095] The readable storage medium provided in the embodiments of the present invention is described below. The readable storage medium described below can be referred to in correspondence with the cable defect detection method described above.

[0096] The present invention also provides a readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the above-described cable defect detection method.

[0097] The readable storage medium may include various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0098] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section.

[0099] Finally, it should be noted that in this document, relationships such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0100] The cable defect detection device, method, apparatus, and readable storage medium provided by the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A cable defect detection device, characterized in that, Includes light source, dual optical fiber, acousto-optic sensor, photoelectric converter, electrical signal processor and differential signal processor; The dual optical fibers include a main optical fiber and a slave optical fiber, both of which are connected to the light source at their input ends. Both the main optical fiber and the slave optical fiber receive the standard optical signal emitted by the light source. The main optical fiber is connected to the cable under test via the acousto-optic sensor. After receiving the ultrasonic signal generated by the partial discharge of the cable under test, the acousto-optic sensor couples the ultrasonic signal to obtain a coupled ultrasonic signal and transmits the coupled ultrasonic signal to the main optical fiber. The coupled ultrasonic signal and the standard optical signal undergo an acousto-optic effect within the main optical fiber to form the optical signal under test. The acousto-optic sensor includes an ultrasonic coupling medium and an acousto-optic medium. The ultrasonic coupling medium is located on the outer surface of the acousto-optic medium, and the main optical fiber exits from halfway through the acousto-optic medium. Both the output end of the main optical fiber and the output end of the slave optical fiber are connected to the electrical signal processor through the photoelectric converter. The input terminal of the differential signal processor is connected to the photoelectric converter, and the output terminal of the differential signal processor is connected to the electrical signal processor. The differential signal processor performs differential calculations on the electrical signal to be tested and the interference electrical signal sent by the photoelectric converter, and sends the differential calculation results to the electrical signal processor so that the electrical signal processor can perform cable defect detection. The electrical signal to be tested is the electrical signal converted from the optical signal to be tested by the photoelectric converter, and the interference electrical signal is the electrical signal converted from the standard optical signal by the photoelectric converter.

2. The cable defect detection equipment according to claim 1, characterized in that, The acoustic-optic sensor further includes: A sound-absorbing device is disposed on the first outer surface of the acousto-optic medium, and an ultrasonic coupling medium is disposed on the second outer surface of the acousto-optic medium, with the first outer surface and the second outer surface being disposed opposite to each other.

3. The cable defect detection equipment according to claim 1, characterized in that, The acoustic-optic sensor is mounted on the surface of the extruded layer of the cable body under test in a bonded manner.

4. A method for detecting cable defects, characterized in that, The method, applied to the cable defect detection equipment according to any one of claims 1 to 3, comprises: Acquire the electrical signal to be tested and the interference electrical signal; the electrical signal to be tested is the electrical signal converted from the optical signal to be tested in the main optical fiber by the photoelectric converter, and the interference electrical signal is the electrical signal converted from the standard optical signal in the secondary optical fiber by the photoelectric converter; the optical signal to be tested is the optical signal generated by the acousto-optic effect of the coupled ultrasonic signal and the standard optical signal in the main optical fiber. Based on the electrical signal to be tested and the interference electrical signal, determine whether the cable to be tested has a defect.

5. The cable defect detection method according to claim 4, characterized in that, The step of determining whether the cable under test has a defect based on the electrical signal to be tested and the interference electrical signal includes: The differential calculation is performed on the electrical signal under test and the interference electrical signal to obtain the differential value; Obtain a preset defect difference threshold, and compare the relationship between the difference value and the preset defect difference threshold; When the difference value is less than the preset defect difference threshold, it is determined that the cable to be tested has no defects; When the difference value is greater than or equal to the preset defect difference threshold, it is determined that the cable to be tested has a defect.

6. A readable storage medium, characterized in that, The readable storage medium stores a computer program that, when executed by a processor, implements the steps of the cable defect detection method as described in any one of claims 4 and 5.

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