Cable outer sheath breakage detection positioning method and device, computer program product, storage medium

Abstract

The application discloses a cable outer sheath breakage detection and positioning method and device, a computer program product and a storage medium. The method comprises the following steps: acquiring a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device being arranged at a first end of a target detection section of a cable outer sheath, the first detection signal comprising at least a first incident signal and a first reflected signal, the second detection device being arranged at a second end of the target detection section, and the second detection signal comprising at least a second incident signal and a second reflected signal; and determining a breakage position of the target detection section based on the first detection signal and the second detection signal. The application solves the technical problem of a complicated cable outer sheath breakage position detection mode and poor detection efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of cable detection, in particular to a cable outer sheath damage detection and positioning method and device, a computer program product and a storage medium. BACKGROUND

[0002] High-voltage cables are important and widely used power transmission equipment today. In actual laying scenarios, a reasonable grounding box can ensure the safe operation of the cable because the internal high-voltage alternating current generates an induced voltage on the metal outer sheath. However, the outer sheath of the cable may be damaged due to external stress, corrosion and other reasons, and it is more complex and time-consuming to directly troubleshoot the cable body.

[0003] In the prior art, a method for detecting and positioning the outer sheath of a high-voltage cable using time-frequency domain signals is adopted. This method directly uses the metal outer sheath as a detection signal injection point, injects the signal directly into the cable metal sheath, and connects a digital oscilloscope to the metal sheath to take incident and reflected signals. After WVD time-frequency domain decomposition, the normalized curve of the incident and reflected signals is calculated, the peak value of the normalized curve is determined to determine the reflected signal, and finally the time difference between the incident signal and the reflected signal and the wave speed are used to calculate the damage location.

[0004] However, the existing method directly injects the signal into the metal outer sheath. In actual cable laying, the metal outer sheath is not exposed for safety reasons, which makes the existing detection method unable to directly inject the signal into the cable. In addition, the existing method only considers one-way transmission of the signal in the cable. In the process of detecting the actual cable in operation, it is more cumbersome to detect after peeling the cable from the line, and the detection efficiency is poor.

[0005] To address the above problems, no effective solutions have been proposed so far. SUMMARY

[0006] The embodiments of the present application provide a cable outer sheath damage detection and positioning method, device, computer program product and storage medium to at least solve the technical problems of complicated cable outer sheath damage location detection and poor detection efficiency.

[0007] According to an aspect of the embodiments of the present application, a method for detecting and locating a damage of a cable outer sheath is provided, comprising: obtaining a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device being arranged at a first end of a target detection section of the cable outer sheath, the first detection signal comprising at least a first incident signal and a first reflected signal, the first incident signal being an incident signal injected by the first detection device into the cable outer sheath, the first reflected signal being a reflected signal generated by the first incident signal reflected by the cable, the second detection device being arranged at a second end of the target detection section, the second detection signal comprising at least a second incident signal and a second reflected signal, the second incident signal being an incident signal injected by the second detection device into the cable outer sheath, the second reflected signal being a reflected signal generated by the second incident signal reflected by the cable; and determining a damage position of the target detection section based on the first detection signal and the second detection signal.

[0008] Optionally, before obtaining the second detection signal, the method further comprises: obtaining the first detection signal; determining whether the target detection section is damaged based on the first detection signal; and obtaining the second detection signal in a case where it is determined that the target detection section is damaged.

[0009] Optionally, the determining of the damage position of the target detection section based on the first detection signal and the second detection signal comprises: determining whether the target detection section is damaged based on the second detection signal; and determining the damage position of the target detection section based on the first detection signal and the second detection signal in a case where it is determined that the target detection section is damaged.

[0010] Optionally, during the obtaining of the first detection signal of the first detection device and the second detection signal of the second detection device, the cable is kept in an operating state.

[0011] Optionally, the first detection device comprises a first signal generator and a first oscilloscope, and the obtaining of the first detection signal comprises: connecting the first detection device to any two phases of a first grounding box arranged at the first end of the target detection section; generating the first incident signal by the first signal generator and injecting the first incident signal into the first grounding box, the first incident signal entering the cable outer sheath from the first grounding box and being reflected by the cable to generate the first reflected signal; and collecting the first incident signal and the first reflected signal by the first oscilloscope.

[0012] Optionally, the second detection device comprises a second signal generator and a second oscilloscope, and the second detection signal is acquired by the following steps: connecting the second detection device to any two phases of a second grounding box, the second grounding box being arranged at a second end of the target detection section; generating a second incident signal by the second signal generator, and injecting the second incident signal into the second grounding box, the second incident signal entering the cable outer sheath along the second grounding box and being reflected by the cable to generate a second reflected signal; and collecting the second incident signal and the second reflected signal by the second oscilloscope.

[0013] Optionally, the damage position of the target detection section is determined based on the first detection signal and the second detection signal, and the method comprises the following steps: determining a first fault distance S A based on the first detection signal, the first fault distance being a distance between the damage point and a first end of the target detection section; determining a second fault distance S B based on the second detection signal, the second fault distance being a distance between the damage point and a second end of the target detection section; acquiring a preset interval L, the preset interval L being a distance between the first grounding box and the second grounding box; and determining position information of the damage point based on the preset interval L, the first fault distance S A and the second fault distance S B .

[0014] According to another aspect of the embodiments of the present application, a cable outer sheath damage detection and positioning device is also provided, comprising: an acquisition module, configured to acquire a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device being arranged at a first end of a target detection section of a cable outer sheath, the first detection signal comprising at least a first incident signal and a first reflected signal, the first incident signal being an incident signal injected into the cable outer sheath by the first detection device, and the first reflected signal being a reflected signal generated by the first incident signal being reflected by the cable outer sheath, the second detection device being arranged at a second end of the target detection section, the second detection signal comprising at least a second incident signal and a second reflected signal, the second incident signal being an incident signal injected into the cable outer sheath by the second detection device, and the second reflected signal being a reflected signal generated by the second incident signal being reflected by the cable outer sheath; and a determination module, configured to determine a damage position of the target detection section based on the first detection signal and the second detection signal.

[0015] According to another aspect of the embodiments of the present application, a computer program product is also provided, comprising a computer program, which, when executed by a processor, implements the steps of any of the above-mentioned cable outer sheath damage detection and positioning methods.

[0016] According to a further aspect of the embodiments of the present application, a computer readable storage medium is also provided, which comprises a stored program, wherein the computer readable storage medium is controlled to execute any of the above cable outer sheath breakage detection and positioning methods when the program is run.

[0017] In the embodiments of the present application, the first detection signal of the first detection device and the second detection signal of the second detection device are acquired, the first detection device is arranged at the first end of the target detection section of the cable outer sheath, the first detection signal at least comprises a first incident signal and a first reflected signal, the first incident signal is an incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is a reflected signal generated by the reflection of the first incident signal through the cable, the second detection device is arranged at the second end of the target detection section, and the second detection signal at least comprises a second incident signal and a second reflected signal, the second incident signal is an incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is a reflected signal generated by the reflection of the second incident signal through the cable; and the breakage position of the target detection section is determined based on the first detection signal and the second detection signal. Through the above method, the breakage position of the outer sheath can be effectively monitored and positioned without interrupting the operation of the cable and without stripping the cable from the line, the detection operation process is simple, and the operation safety and the maintenance efficiency of the system are improved. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings, which are included to provide a further understanding of the present application and are incorporated in and constitute a part of this application, illustrate embodiments of the present application and serve to explain the present application. In the drawings:

[0019] Figure 1 FIG. 1 is a hardware structure block diagram of a computer terminal of a cable outer sheath breakage detection and positioning method according to an embodiment of the present application;

[0020] Figure 2 FIG. 2 is a flowchart of a cable outer sheath breakage detection and positioning method according to an optional embodiment of the present application;

[0021] Figure 3 FIG. 3 is a structure block diagram of a cable outer sheath breakage detection and positioning method according to an embodiment of the present application;

[0022] Figure 4 FIG. 4 is a flowchart of a cable outer sheath breakage detection and positioning method according to an optional embodiment of the present application;

[0023] Figure 5 FIG. 5 is a structure diagram of a cable outer sheath breakage detection and positioning device according to an optional embodiment of the present application;

[0024] Figure 6is a structural schematic diagram of a detection device according to an optional embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to enable persons skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by persons skilled in the art without creative labor should belong to the protection scope of the present application.

[0026] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0027] According to an embodiment of the present application, an embodiment of a cable outer sheath breakage detection and positioning method is provided. It should be noted that the steps shown in the flowchart of the drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in an order different from that shown herein.

[0028] The method embodiment can be executed in a computer terminal or similar computing device containing a memory and a processor. For example, as shown in Figure 1 the computer terminal can include one or more processors 102 (the processor can include but not limited to a central processing unit (CPU), a graphics processing unit (GPU), a digital signal processing (DSP) chip, a microprocessor (MCU), a programmable logic device (FPGA), a neural network processor (NPU), a tensor processor (TPU), an artificial intelligence (AI) type processor, etc. processing device) and a memory 104 for storing data. Optionally, the above-mentioned computer terminal can also include a transmission device 106 for communication function, an input and output device 108, and a display 110. Those skilled in the art can understand that Figure 1The illustrated structure is merely schematic and does not limit the structure of the computer terminal described above. For example, the computer terminal can include more or fewer components than those described above, or have a different configuration than that described above.

[0029] The memory 104 can be used to store computer programs, such as software programs of application software and modules, such as the computer program corresponding to the cable outer sheath breakage detection and positioning method in the embodiments of the present application. The processor 102 executes various functional applications and data processing by running the computer programs stored in the memory 104, that is, implements the cable outer sheath breakage detection and positioning method described above. The memory 104 can include a high-speed random access memory, and can also include a non-volatile memory, such as one or more magnetic storage devices, flash memories, or other non-volatile solid-state memories. In some examples, the memory 104 can further include a memory remotely arranged with respect to the processor 102, and these remote memories can be connected to the mobile terminal through a network. Examples of the above-mentioned network include but are not limited to the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof.

[0030] The transmission device 106 is used to receive or send data via a network. Specific examples of the above-mentioned network can include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (NIC), which can be connected to other network devices through a base station so as to be able to communicate with the Internet. In one example, the transmission device 106 can be a radio frequency (RF) module, which is used to communicate with the Internet in a wireless manner.

[0031] The display 110 can be, for example, a touch screen type liquid crystal display (LCD). The liquid crystal display can enable a user to interact with a user interface of the mobile terminal. In some embodiments, the above-mentioned mobile terminal has a graphical user interface (GUI), and a user can interact with the GUI through finger contact and / or gestures on a touch-sensitive surface. The human-computer interaction function can optionally include the following interactions: creating web pages, drawing, word processing, creating electronic documents, gaming, video conferencing, instant messaging, sending and receiving e-mails, call interfaces, playing digital videos, playing digital music, and / or web browsing, and executable instructions for executing the above-mentioned human-computer interaction functions are configured / stored in one or more computer program products or readable storage media executable by the processor.

[0032] The embodiments of the present application provide a cable outer sheath breakage detection and positioning method running on the above-mentioned computer terminal, Figure 2is a flow chart of a cable outer sheath breakage detection and positioning method according to an embodiment of the present application, as shown in Figure 2 The flow chart comprises the following steps:

[0033] Step S21: Obtain a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device is arranged at a first end of a target detection section of a cable outer sheath, the first detection signal at least comprises a first incident signal and a first reflected signal, the first incident signal is an incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is a reflected signal generated by the first incident signal reflected by the cable, the second detection device is arranged at a second end of the target detection section, and the second detection signal at least comprises a second incident signal and a second reflected signal, the second incident signal is an incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is a reflected signal generated by the second incident signal reflected by the cable.

[0034] Specifically, the first detection device and the second detection device use the same type and function of equipment to inject detection signals to ensure that the first reflected signal and the second reflected signal corresponding to the breakage position of the cable outer sheath received are corresponding (the signal pulse amplitude and pulse frequency are the same). The first incident signal and the second incident signal are signals transmitted by the first detection device and the second detection device to the first end of the target detection section and the second end of the target detection section, and the first reflected signal and the second reflected signal are reflected signals received by the first detection device and the second detection device at the breakage position of the cable outer sheath or the other end, the incident signal and the reflected signal are incident signals and reflected signals in time-frequency domain reflection (TDR, Time-Domain Reflectonetry), and the time-frequency domain reflection is a method for testing the principle of reflection of electromagnetic waves in the cable when encountering impedance change points.

[0035] It should be noted that the first detection device and the second detection device can be the same detection device, which first injects the first detection signal to the first end of the target detection section, and whether to inject the second detection signal to the second end of the target detection section can be determined according to the feedback result of the first detection signal. Since the first detection signal and the second detection signal do not need to be injected at the same time, the same detection device can be used for cable outer sheath breakage detection and positioning.

[0036] Step S22: Determine the breakage position of the target detection section based on the first detection signal and the second detection signal.

[0037] Specifically, when the first incident signal and the second incident signal are transmitted to the damaged position of the target detection end, due to the change of the characteristic impedance of the cable, the incident signal is reflected at the damaged point of the cable, and then the first reflected signal and the second reflected signal are formed, the first reflected signal and the second reflected signal return to the incident end and can be captured by the detection device, and the damaged position of the target detection end can be determined through analysis and calculation of the reflected signal.

[0038] Through the above steps, the first detection signal of the first detection device and the second detection signal of the second detection device are obtained, the first detection device is arranged at the first end of the target detection section of the cable outer sheath, the first detection signal at least includes the first incident signal and the first reflected signal, the first incident signal is the incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is the reflected signal generated by the first incident signal reflected by the cable, the second detection device is arranged at the second end of the target detection section, and the second detection signal at least includes the second incident signal and the second reflected signal, the second incident signal is the incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is the reflected signal generated by the second incident signal reflected by the cable; based on the first detection signal and the second detection signal, the damaged position of the target detection section is determined. Through the above method, the damaged position of the outer sheath can be effectively monitored and positioned without interrupting the operation of the cable and without stripping the cable from the line, the detection operation process is simple, and the operation safety and maintenance efficiency of the system are improved.

[0039] In the embodiment, the first detection device and the second detection device analyze the received first reflected signal and second reflected signal in time-frequency domain, and identify the time delay of the reflected signal by using Wigner-Ville distribution and normalized cross-correlation coefficient, that is, the time difference between the incident signal and the reflected signal of the first detection signal is combined with the propagation speed of electromagnetic wave in the cable, so that the distance between the damaged point and the signal injection point can be calculated, and the distance between the damaged point and the second end of the target detection section can be calculated if the second detection signal also generates a reflected signal.

[0040] Optionally, before the step S21 of obtaining the second detection signal, the method further comprises the following steps:

[0041] Step S201: obtaining the first detection signal;

[0042] Specifically, the first detection signal in the first detection device is obtained, and the first detection signal is a time-frequency domain signal, which can be a time-frequency domain signal with time domain characteristics and frequency domain characteristics generated by the first detection device.

[0043] It should be noted that the time-frequency domain of the first detection signal can be adjusted according to the laying condition of the high-voltage cable in the specific environment, that is, the first detection signal is adjusted to a suitable frequency so as to facilitate the detection device to detect and receive the incident signal.

[0044] Step S202: determining whether the target detection section is damaged based on the first detection signal;

[0045] Specifically, by the first detection signal emitted and received by the first detection device, the first detection signal includes the emitted incident signal and the received reflected signal, the time difference between the emission and the reception of the first detection signal is calculated, and the position of the reflected signal in the damaged section of the cable is calculated; or the first detection device does not receive the reflected signal in the first detection signal, which proves that the target detection section has no damage point.

[0046] Step S203: obtaining the second detection signal in the case where it is determined that the target detection section is damaged.

[0047] Specifically, when the first detection device receives the reflected signal in the first detection signal, it is determined whether the reflected signal comes from the damage position of the target detection section or the other end of the target detection section, and the second detection signal is injected by the second detection device to determine the damage position of the target detection section in combination with the first detection signal and the second detection signal.

[0048] In the embodiment, the result fed back by the first detection device can quickly determine whether the target detection section of the cable has damage through the prior detection, and it can be determined whether further detailed detection is needed, thereby avoiding unnecessary waste of resources, and the embodiment is suitable for preliminary screening of large-scale cable network and improves the pertinence and efficiency of detection.

[0049] Optionally, in step S22, the damage position of the target detection section is determined based on the first detection signal and the second detection signal, including:

[0050] Step S221: determining whether the target detection section is damaged based on the second detection signal;

[0051] Specifically, when the first detection device receives the reflected signal in the first detection signal, it is preliminarily determined that the target detection section has damage, the second detection signal is injected by the second detection device and the other end of the target detection section, and the second detection signal received by the second detection device is compared with the first detection signal to determine whether the target detection section has damage.

[0052] It should be noted that in step S203, the target detection section is preliminarily judged to have a damage condition by the first detection signal, but since the detection signal is bidirectional or multi-directional propagation in the cable, it cannot be determined that there is a damage condition in the target detection section only by the first detection signal, and the second detection signal needs to be combined for comprehensive judgment. At the same time, the two ends of the target detection section also have different impedances from the normal cable, and the first detection signal will also produce a reflected signal at the endpoint of the target detection section. This reflected signal needs to be filtered together with the second detection signal before the target detection section can be truly determined whether there is a damage condition.

[0053] Step S222: In the case where the target detection section is determined to have a damage condition, the damage position of the target detection section is determined based on the first detection signal and the second detection signal.

[0054] Specifically, the first detection signal and the second detection signal are periodic input time-frequency domain characteristic signals, and the continuous incident signal and reflected signal are collected by the first detection device and the second detection device. Since the characteristics of the two signals are similar, the overall collected signal can be feature extracted to obtain a frequency spectrum or formula containing both time domain features and frequency domain features. Specifically, the time difference between the incident signal and the reflected signal is obtained by calculating the time-frequency energy of the incident signal and the cross-correlation curve of the entire sampling signal, and then the distance from the fault point to the two ends of the target detection section is calculated by the detection signal electromagnetic wave speed (signal propagation speed) to locate the high-voltage cable outer sheath damage position. The embodiment adopts a double-end detection mode, which can improve the accuracy of detection, and the signals are detected at the two ends of the target detection section, which can effectively locate the damage point.

[0055] Optionally, in the above steps, during the process of obtaining the first detection signal of the first detection device and the second detection signal of the second detection device, the cable remains in a running state. The cable detection can be performed while the cable is running normally, so it is not necessary to interrupt the power or communication service, thereby ensuring the continuity and stability of power supply or service.

[0056] Optionally, in step S21, the first detection device includes a first signal generator and a first oscilloscope, and the first detection signal is obtained, including the following steps:

[0057] Step S2111: connecting the first detection device to any two phases of the first grounding box, and the first grounding box is arranged at the first end of the target detection section;

[0058] Specifically, as Figure 5 , Figure 6As shown, the target detection section adopts the common three single-core cable cross interconnection grounding mode, the metal sheath of the three cables constitutes the grounding system of the cable through cross interconnection, the first detection device detects the first grounding box cable of the grounding system, in the detection process, the first signal generator and the first oscilloscope in the first detection device need to be connected, and two outgoing lines are connected to two phases of the first grounding box. Among them, the grounding box A is one of the first grounding box and the second grounding box, and the grounding box B is the other one of the first grounding box and the second grounding box.

[0059] In the embodiment, the first signal generator is used to emit the first detection signal, and the first oscilloscope is used to collect the incident signal and the reflected signal; the first detection device further comprises a first host computer, which is used to process and store signals and simultaneously connect the two outgoing lines of the first oscilloscope and the first signal generator.

[0060] Step S2112: a first signal generator is used to generate a first incident signal, and the first incident signal is injected into the first grounding box, the first incident signal enters the cable outer sheath along the first grounding box, and the first incident signal is reflected through the cable to generate a first reflected signal;

[0061] Specifically, the first signal generator generates a first incident signal, which is injected into the target detection section through the first grounding box, and the other end of the target detection section or the cable breakage of the target detection section reflects the first incident signal to generate a first reflected signal returning to the first detection device.

[0062] Step S2113: a first oscilloscope is used to collect the first incident signal and the first reflected signal.

[0063] Specifically, the first oscilloscope collects the first incident signal and the first reflected signal and transmits the signal data to the first host computer, so as to facilitate the first host computer to analyze and calculate the cable breakage position distance.

[0064] Optionally, in step S21, the second detection device comprises a second signal generator and a second oscilloscope, and a second detection signal is obtained, comprising the following steps:

[0065] Step S2121: connecting the second detection device to any two phases of the second grounding box, and the second grounding box is arranged at the second end of the target detection section;

[0066] Specifically, as shown in Figure 5 、 Figure 6 The second detection device detects the second grounding box cable of the grounding system, and in the detection process, the second signal generator and the second oscilloscope in the second detection device need to be connected, and two outgoing lines are connected to two phases of the second grounding box.

[0067] Step S2122: generating a second incident signal by a second signal generator, and injecting the second incident signal into the second grounding box, the second incident signal entering the cable outer sheath along the second grounding box, and being reflected by the cable to generate a second reflected signal;

[0068] Specifically, the second signal generator generates the second incident signal, the second incident signal is injected into the target detection section through the second grounding box, and the second incident signal is reflected by the cable breakage of the target detection section or the other end of the target detection section to generate a second reflected signal returning to the second detection device.

[0069] Step S2123: collecting the second incident signal and the second reflected signal by the second oscilloscope.

[0070] Specifically, the second oscilloscope collects the second incident signal and the second reflected signal in reverse and transmits the signal data to the second host computer, so as to facilitate the second host computer to analyze and calculate the cable breakage position distance.

[0071] In an embodiment of the present application, the method of detecting the position of the cable breakage by specifically arranging the signal generator, the oscilloscope and the host computer in the first detection device and the second detection device, and connecting the first detection device and the second detection device to the grounding box makes the detection process more standardized and automated, reduces human operation errors, and the first detection device and the second detection device simultaneously inject and collect frequency domain signals at both ends of the target detection section, thereby improving the reliability of the detection result.

[0072] Optionally, in step S22, based on the first detection signal and the second detection signal, the breakage position of the target detection section is determined, including the following steps:

[0073] Step S223: determining a first fault distance S A based on the first detection signal, the first fault distance being the distance between the breakage point and the first end of the target detection section;

[0074] Specifically, based on the first detection signal, the time difference between the first incident signal and the first reflected signal is used to calculate the distance S A between the fault point and the signal transmission point S

[0075] Step S224: determining a second fault distance S B based on the second detection signal, the second fault distance being the distance between the breakage point and the second end of the target detection section;

[0076] Specifically, based on the second detection signal, the time difference between the second incident signal and the second reflected signal is used to calculate the distance S B, positioning the distance between the outer sheath of the high-voltage cable and the second end of the target detection section.

[0077] Step S225: obtaining a preset interval L, the preset interval L being the distance between the first grounding box and the second grounding box;

[0078] Specifically, the distance L between the first grounding box and the second grounding box is obtained by a grounding box interval measurement method, which also uses the time-frequency domain reflection method to measure, that is, an incident signal is injected at the first grounding box or the second grounding box, the incident signal is received at the second grounding box or the first grounding box, or the reflected signal is received at the same grounding box, and the distance L between the first grounding box and the second grounding box is measured in combination with the electromagnetic wave speed.

[0079] Step S226: determining the position information of the damage point based on the preset interval L, the first fault distance S A and the second fault distance S B .

[0080] Specifically, if the calculation is accurate, there is a relationship of L=S A +S B , but the relationship of the three satisfies the calculation relative error e, then e=L-(S A +S B . If the calculation error satisfies that e does not exceed 0.1 m, the position information of the fault point can be determined, and the error data can be adjusted according to specific indicators. The calculation method based on the signal reflection distance in the embodiment can accurately calculate the absolute position of the damage point, which is helpful for optimizing the maintenance strategy and resource allocation of the cable.

[0081] The application also provides a preferred embodiment of a cable outer sheath damage detection and positioning method, which mainly solves the problem that the detection method through the double grounding boxes cannot determine which section of the cable is damaged if there is a reflected signal in the sampled waveform after the signal is bidirectionally propagated when the signal is injected, as shown in Figure 4 The method comprises the following steps:

[0082] Step one: determining a target cable section to be detected, and selecting a first grounding box at a first end of the target detection section for detection;

[0083] The detection work mainly comprises connecting the first detection device to any two phases of the first grounding box, then using the first signal generator to generate a time-frequency domain signal and injecting the signal into the first grounding box, and the signal will enter the metal sheath of the two phases from the first grounding box, at this time the signal is bidirectionally propagated.

[0084] Step two: the first oscilloscope collects the first incident signal and the first reflected signal, and transmits the signals to the first host computer for calculation and processing to obtain the time difference between the first incident signal and the first reflected signal, calculate the cable outer sheath damage position, and detect the fault distance S A ;

[0085] When the signal is reflected after passing through the cable damage section, the first incident signal and the first reflected signal can be collected by the first oscilloscope. The first oscilloscope transmits the sampling information to the first host computer. The first host computer can process the signal by time-frequency domain decomposition method such as Wigner-Ville distribution and normalized cross-correlation coefficient method to obtain the time difference between the first incident signal and the first reflected signal. The wave speed and the time difference are used to obtain the cable outer sheath damage position.

[0086] Step three: after the first host computer obtains the information and stores it, it is checked whether there is a first reflected signal due to the cable outer sheath. If there is no damage signal, the other two phases of the first grounding box are replaced, and the process jumps to step one. If there is no fault signal in any two phases of the first grounding box, it can be judged that the target detection section has no outer sheath damage. If a damage signal is detected, the second end of the target detection section is moved to the second grounding box for detection.

[0087] Step four: the second grounding box at the second end of the target detection section is selected for detection.

[0088] Step five: the second oscilloscope collects the second incident signal and the second reflected signal, and transmits the signals to the second host computer for calculation and processing to obtain the time difference between the second incident signal and the second reflected signal, calculate the cable outer sheath damage position, and detect the fault distance S B ;

[0089] Step six: measure the distance L between the first grounding box and the second grounding box, and calculate the relative error between the fault distance S A , the fault distance S B , and L.

[0090] The processing method after the above signal collection and the principle of determining the cable outer sheath damage position are as follows:

[0091] By periodically inputting time-frequency domain characteristic signals, the oscilloscope can collect continuous incident signals and reflected signals. Since the characteristics of the two signals are similar, the overall collected signals can be extracted for features. The time-frequency domain matrix W r (t,ω) of the incident signal and the time-frequency domain matrix W s(t,ω), to obtain a spectrum chart containing both time domain characteristics and frequency domain characteristics, and the following cross-correlation coefficient C sr is calculated:

[0092]

[0093] wherein E r =∫∫W r (t,ω)dωdτ; E s =∫∫W s (t,ω)dωdτ.

[0094] In the above formula, E r and E s are the energies of the incident signal and the reflected signal respectively, for normalization of the entire C sr curve, specifically by calculating the time-frequency energy of the incident signal and the cross-correlation curve of the entire sampling signal, wherein the normalized cross-correlation coefficient is 1 at the signal time center of the incident signal, and the second peak is the time center of the first reflected signal, so that the difference Δt between the incident signal and the reflected signal can be obtained, and the distance S of the fault point from the signal transmitting point can be calculated according to the electromagnetic wave velocity by the formula:

[0095]

[0096] , so as to locate the damage of the outer sheath of the high-voltage cable.

[0097] After obtaining the sampling waveforms of the incident signal and the reflected signal, the terminal reflected signal needs to be determined according to the distance between the two grounding boxes of the target detection section and filtered out. Since the sampling signal contains the incident signal, the reflected signal at the fault point, and the reflected signal at the other grounding box, for the cable with known distance between the two grounding boxes, the reflected signal at the grounding box can be directly taken out; but for the cable with unknown interval, the two grounding boxes need to be compared to determine the reflected signal with the same amplitude and the same position, if there are two signals meeting the above conditions, the second signal is removed, and at this time, the damage of the outer sheath of the cable is most likely to occur between the two grounding boxes.

[0098] In addition to the above case that the damage of the outer sheath of the cable occurs between the two grounding boxes, most of the cases exist in other cases, and the fault distances S A and S B are obtained by detecting the two grounding boxes, and the distance L between the two grounding boxes is determined by the above grounding box distance measurement method, and the relationship among the above three satisfies the calculation of the relative error e:

[0099] e=L-(S A +S B );

[0100] If the calculation error satisfies e≤0.1m, the position information of the fault point can be determined, and the error value can be adjusted according to specific indexes.

[0101] Through the description of the above embodiments, it can be seen that the embodiments of the application have the following beneficial effects:

[0102] 1) By considering the problem that the metal outer sheath cannot be directly connected in the actual operation process of the high-voltage cable, the grounding box is used as a medium for signal input and sampling to realize the detection of the outer sheath of the cable in operation.

[0103] 2) By considering the problem of bidirectional transmission of signals, the detection method of determining the fault section of one end of the cable by using two grounding boxes is adopted to avoid the problems that the broken section cannot be determined after the reflection signals are superimposed and the accurate positioning cannot be achieved.

[0104] Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be realized by means of software and the necessary general hardware platform, and of course, it can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the application or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes a plurality of instructions for making a terminal device (which can be a mobile phone, computer, server, or network device, etc.) execute the method described in each embodiment of the application.

[0105] In the present embodiment, a cable outer sheath breakage detection and positioning device is also provided, which is used to realize the above embodiments and preferred embodiments, and will not be described again. As used below, the term "module" can be a combination of software and / or hardware that realizes a predetermined function. Although the device described in the following embodiments is preferably realized in software, the realization of hardware, or a combination of software and hardware, is also possible and is contemplated.

[0106] Figure 3 is a structural block diagram of a cable outer sheath breakage detection and positioning device according to one embodiment of the application, as Figure 3As shown, the device comprises: an acquisition module 42, the acquisition module 42 is used for acquiring a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device is arranged at a first end of a target detection section of a cable outer sheath, the first detection signal at least comprises a first incident signal and a first reflected signal, the first incident signal is an incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is a reflected signal generated by the first incident signal reflecting on the cable outer sheath, the second detection device is arranged at a second end of the target detection section, and the second detection signal at least comprises a second incident signal and a second reflected signal, the second incident signal is an incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is a reflected signal generated by the second incident signal reflecting on the cable outer sheath; and a determination module 44, the determination module 44 is used for determining a damage position of the target detection section based on the first detection signal and the second detection signal.

[0107] Through the above device, the acquisition module 42 is used for acquiring a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device is arranged at a first end of a target detection section of a cable outer sheath, the first detection signal at least comprises a first incident signal and a first reflected signal, the first incident signal is an incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is a reflected signal generated by the first incident signal reflecting on the cable outer sheath, the second detection device is arranged at a second end of the target detection section, and the second detection signal at least comprises a second incident signal and a second reflected signal, the second incident signal is an incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is a reflected signal generated by the second incident signal reflecting on the cable outer sheath; and a determination module 44, the determination module 44 is used for determining a damage position of the target detection section based on the first detection signal and the second detection signal. The device can effectively monitor and locate the damage position of the outer sheath without interrupting the operation of the cable and without stripping the cable from the line for detection, the detection operation process is simple, and the operation safety and maintenance efficiency of the system are improved.

[0108] It should be noted that the above various modules can be realized by software or hardware, and for the latter, the following implementation manners can be used, but are not limited thereto: the above modules are located in the same processor; or the above various modules are located in different processors in any combination.

[0109] Optionally, in addition to the above acquisition module 42 and determination module 44, other modules can also be included, for example, the cable outer sheath damage detection and positioning device further comprises a filtering module, the filtering module is used for automatically eliminating the reflected signals generated at both ends of the target detection section; and a communication module, the communication module is used for transmitting the real-time detection results and information to a remote monitoring center or a cloud end through wired or wireless means.

[0110] The embodiment of the present application also provides a computer program product, comprising a computer program, which, when executed by a processor, implements the steps in any one of the cable outer sheath breakage detection and positioning method embodiments.

[0111] The embodiment of the present application also provides a computer program product, which is arranged to execute the steps in any one of the cable outer sheath breakage detection and positioning method embodiments.

[0112] Optionally, in the embodiment, the computer program is arranged to execute the following steps:

[0113] Step S1, a first detection signal of a first detection device and a second detection signal of a second detection device are acquired, the first detection device is arranged at a first end of a target detection section of a cable outer sheath, the first detection signal at least comprises a first incident signal and a first reflected signal, the first incident signal is an incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is a reflected signal generated by the first incident signal reflected by the cable, the second detection device is arranged at a second end of the target detection section, and the second detection signal at least comprises a second incident signal and a second reflected signal, the second incident signal is an incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is a reflected signal generated by the second incident signal reflected by the cable.

[0114] Step S2, a breakage position of the target detection section is determined based on the first detection signal and the second detection signal.

[0115] The embodiment of the present application also provides a storage medium, which stores a computer program, wherein the computer program is arranged to execute the steps in any one of the method embodiments when running.

[0116] Optionally, in the embodiment, the storage medium can be arranged to store a computer program for executing the following steps:

[0117] Step S1, a first detection signal of a first detection device and a second detection signal of a second detection device are acquired, the first detection device is arranged at a first end of a target detection section of a cable outer sheath, the first detection signal at least comprises a first incident signal and a first reflected signal, the first incident signal is an incident signal injected by the first detection device to the cable outer sheath, and the first reflected signal is a reflected signal generated by the first incident signal reflected by the cable, the second detection device is arranged at a second end of the target detection section, and the second detection signal at least comprises a second incident signal and a second reflected signal, the second incident signal is an incident signal injected by the second detection device to the cable outer sheath, and the second reflected signal is a reflected signal generated by the second incident signal reflected by the cable.

[0118] Step S2, determining the damage position of the target detection section based on the first detection signal and the second detection signal.

[0119] Optionally, in the embodiment, the storage medium can include, but is not limited to, a U disk, a read-only memory (ROM), a random access memory (RAM), a mobile hard disk, a magnetic disk or an optical disk, and various storage media that can store computer programs.

[0120] In the above embodiments of the present application, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0121] In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other ways. Among them, the above-described device embodiments are only schematic, for example, the division of the units can be a logical function division, and actual implementation can have another division way, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or modules shown or discussed can be indirect coupling or communication connection through some interfaces, units or modules, which can be electrical or other forms.

[0122] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or they can be distributed to multiple units. According to actual needs, part or all of the units can be selected to achieve the purpose of the embodiment.

[0123] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0124] The integrated unit, if implemented in the form of a software function unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application, essentially or in other words, the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present application. The aforementioned storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0125] The above is only the preferred embodiment of the present application, and it should be pointed out that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A method for detecting and locating damage of a cable outer sheath, characterized in that: The method comprises the following steps: Acquire a first detection signal of a first detection device and a second detection signal of a second detection device, wherein the first detection device is disposed at a first end of a target detection section of the cable outer sheath, the first detection signal includes at least a first incident signal and a first reflected signal, the first incident signal being an incident signal injected into the cable outer sheath by the first detection device, and the first reflected signal being a reflected signal generated by the reflection of the first incident signal by the cable, the second detection device being disposed at a second end of the target detection section, the second detection signal including at least a second incident signal and a second reflected signal, the second incident signal being an incident signal injected into the cable outer sheath by the second detection device, and the second reflected signal being a reflected signal generated by the reflection of the second incident signal by the cable; determining a damage position of the target detection segment based on the first detection signal and the second detection signal; Before acquiring the second detection signal, the method further includes the following steps: acquiring the first detection signal; determining, based on the first detection signal, whether the target detection segment is damaged; When it is determined that the target detection segment is damaged, acquiring the second detection signal; Wherein, determining the damage position of the target detection segment based on the first detection signal and the second detection signal includes: determining, based on the second detection signal, whether the target detection segment is damaged; When it is determined that the target detection segment is damaged, a damaged position of the target detection segment is determined based on the first detection signal and the second detection signal.

2. The method according to claim 1, characterized in that During the process of acquiring the first detection signal of the first detection device and the second detection signal of the second detection device, the cable remains in an operating state.

3. The method according to claim 1, characterized in that The first detection device includes a first signal generator and a first oscilloscope, and obtaining the first detection signal includes the following steps: connecting the first detection device to any two phases of a first grounding box, the first grounding box being disposed at a first end of the target detection section; The first signal generator is used to generate a first incident signal, and the first incident signal is injected into the first grounding box. The first incident signal enters the outer sheath of the cable along the first grounding box and is reflected by the cable to generate a first reflected signal. The first incident signal and the first reflected signal are collected using the first oscilloscope.

4. The method according to claim 3, characterized in that The second detection device includes a second signal generator and a second oscilloscope, and obtaining the second detection signal includes the following steps: connecting the second detection device to any two phases of a second grounding box, the second grounding box being disposed at the second end of the target detection section; generating a second incident signal by the second signal generator, and injecting the second incident signal into the second grounding box, so that the second incident signal enters the outer sheath of the cable along the second grounding box and is reflected by the cable to generate a second reflected signal; The second incident signal and the second reflected signal are collected by the second oscilloscope.

5. The method according to claim 4, characterized in that Determining a damage position of the target detection segment based on the first detection signal and the second detection signal includes the following steps: Based on the first detection signal, a first fault distance S is determined. A , the first fault distance is the distance between the damage point and the first end of the target detection segment; Based on the second detection signal, a second fault distance S is determined. B , the second fault distance is the distance between the damage point and the second end of the target detection segment; Obtaining a preset distance L, where the preset distance L is the distance between the first grounding box and the second grounding box; Based on the preset distance L, the first fault distance S A and the second fault distance S B , determine the location information of the damaged point.

6. A cable outer sheath damage detection and positioning device, characterized in that: include: an acquisition module, wherein the acquisition module is used to acquire a first detection signal of a first detection device and a second detection signal of a second detection device, the first detection device being arranged at a first end of a target detection section of the cable outer sheath, the first detection signal comprising at least a first incident signal and a first reflected signal, the first incident signal being an incident signal injected into the cable outer sheath by the first detection device, and the first reflected signal being a reflected signal generated by reflection of the first incident signal by the cable outer sheath, the second detection device being arranged at a second end of the target detection section, the second detection signal comprising at least a second incident signal and a second reflected signal, the second incident signal being an incident signal injected into the cable outer sheath by the second detection device, and the second reflected signal being a reflected signal generated by reflection of the second incident signal by the cable outer sheath; Wherein, the acquisition module is further used for: acquiring the first detection signal; determining, based on the first detection signal, whether the target detection segment is damaged; When it is determined that the target detection segment is damaged, acquiring the second detection signal; a determination module, configured to determine a damage position of the target detection segment based on the first detection signal and the second detection signal; Wherein, the determining module is further used for: determining, based on the second detection signal, whether the target detection segment is damaged; When it is determined that the target detection segment is damaged, a damaged position of the target detection segment is determined based on the first detection signal and the second detection signal.

7. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the cable outer sheath damage detection and positioning method according to any one of claims 1 to 5 are implemented.

8. A computer-readable storage medium, characterized in that The computer-readable storage medium includes a stored program, wherein when the program is executed, the computer-readable storage medium is controlled, and the device in which it is located executes the cable outer sheath damage detection and positioning method according to any one of claims 1 to 5.

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