Method and device for determining aging time of cable sheath protector

Abstract

The invention discloses a method and a device for determining aging time of a cable sheath protector. The method comprises the steps that a first resistive current of a first cable sheath protector at a target moment and a first voltage of the first cable sheath protector in a normal operation state are acquired, and the target moment is a moment when an adjustable parallel resonator electrically connected with the first cable sheath protector is in a resonance state; the first resistive current is a resistive component of the leakage current at the target moment; calculating a first insulation resistance according to the first resistive current and the first voltage; and matching the first insulation resistance with a preset relation library to obtain first aging time of the sheath of the first cable sheath protector at the target moment. The technical problems that the efficiency of calculating the aging time of the cable sheath protector is low and the cost is high due to the fact that the insulation resistance of the cable sheath protector can only be monitored under the power failure condition in the prior art are solved.

Description

Technical Field

[0001] The present application relates to the field of electric power technology, and in particular to a method and device for determining the aging time of a cable sheath protector. Background Art

[0002] The cable sheath protector is an important device that protects the cable sheath from various overvoltages. It can have a variety of different grounding methods, including: (1) direct grounding, that is, one end is directly grounded and the other end is grounded through the sheath protector; (2) protection node, which can be further divided into: the midpoint is directly grounded and the shields at both ends are grounded through the protective layer; the midpoint is grounded through the sheath protection and the two ends are directly grounded; (3) sheath cross interconnection. Among the above-mentioned grounding methods, direct grounding will cause the protector to bear the greatest voltage risk.

[0003] At present, when measuring the insulation resistance of the cable sheath protector, the relevant technology usually uses a megohmmeter to apply a DC power supply for preliminary testing in a power outage state. Therefore, it can only be tested during regular inspections or when a fault occurs, and it is impossible to monitor the insulation state of the cable sheath protector in real time, making it impossible to detect damage or failure of the cable sheath protector in time. At the same time, a power outage in the traditional pre-test will cause a lot of economic losses, resulting in high measurement costs.

[0004] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0005] An embodiment of the present application provides a method and device for determining the aging time of a cable sheath protector, so as to at least solve the technical problem that the related art can only monitor the insulation resistance of the cable sheath protector when the power is off, resulting in low efficiency and high cost in calculating the aging time of the cable sheath protector.

[0006] According to one aspect of an embodiment of the present application, a method for determining an aging time of a cable sheath protector is provided, comprising: obtaining a first resistive current of a first cable sheath protector at a target moment and a first voltage of the first cable sheath protector under normal operating conditions, wherein the target moment is a moment when an adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is a resistive component of a leakage current of the first cable sheath protector at the target moment; calculating a first insulation resistance of the first cable sheath protector at the target moment based on the first resistive current and the first voltage; matching the first insulation resistance with a preset relationship library to obtain a first aging time of a sheath of the first cable sheath protector at the target moment, wherein the relationship library stores a plurality of sets of corresponding relationships between insulation resistances and aging times.

[0007] Optionally, obtaining a first resistive current of the first cable sheath protector at a target moment and a first voltage of the first cable sheath protector under normal operating conditions includes: in the process of adjusting the inductance value of the adjustable parallel resonator from a minimum value toward a maximum value, obtaining the leakage current of the first cable sheath protector by using a leakage current monitoring device, determining the target moment when the leakage current is at a trough position, and using the leakage current at the target moment as the first resistive current of the first cable sheath protector; obtaining the first voltage of the first cable sheath protector under normal operating conditions by using a voltage monitoring device.

[0008] Optionally, the adjustable parallel resonator includes: an inductor and a rotating structure for adjusting the access state of the inductor, wherein an adjustable parallel resonator access control instruction initiated by a client is received, wherein the adjustable parallel resonator access control instruction carries a digital signal for controlling the access state of the adjustable parallel resonator; when the digital signal is a valid value, the adjustable parallel resonator is controlled to be electrically connected to the first cable sheath protector; when the digital signal is an invalid value, the adjustable parallel resonator is controlled to be electrically disconnected from the first cable sheath protector.

[0009] Optionally, the expression for the value range of the inductance value of the adjustable parallel resonator is as follows:

[0010]

[0011] Where, L represents the inductance of the adjustable parallel resonator, K max Indicates the upper limit coefficient of the reactor, K mim Indicates the lower limit coefficient of the reactor, C max Indicates the maximum capacitance value of multiple second cable sheath protectors under normal operation and leakage current less than the preset threshold, C mim It represents the minimum capacitance value of multiple second cable sheath protectors under normal operating conditions and when the leakage current is less than a preset threshold value. The second cable sheath protectors are of the same model as the first cable sheath protectors. ω represents the electrical angular velocity.

[0012] Optionally, the type of the leakage current monitoring device includes at least one of the following: a current transformer, a Hall effect sensor device, and a Rogowski coil.

[0013] Optionally, the value range of the leakage current monitored by the leakage current monitoring device is expressed as follows:

[0014]

[0015] Among them, U min Indicates the minimum operating voltage at both ends of the first cable sheath protector when it is working normally, U maxIndicates the maximum operating voltage at both ends of the first cable sheath protector when it is working normally, R max It indicates the maximum insulation resistance value of multiple second cable sheath protectors under normal operation and leakage current less than the preset threshold. min It indicates the minimum insulation resistance value of multiple second cable sheath protectors under normal operating conditions and when the leakage current is less than a preset threshold value. The second cable sheath protectors are of the same model as the first cable sheath protectors.

[0016] Optionally, the process of constructing the relationship library includes: determining multiple second inductive sheath protectors of the same model as the first cable sheath protector; for each second cable sheath protector, obtaining the second resistive current and the second aging time of the second cable sheath protector at multiple moments, and the second voltage of the second cable sheath protector under normal operating conditions, and calculating the second insulation resistance of the second cable sheath protector at multiple moments based on the multiple second resistive currents and second voltages; determining the correspondence between the second insulation resistance and the second aging time of the second cable sheath protector at multiple moments; and constructing a relationship library based on the correspondence between the second insulation resistance and the second aging time of the multiple second cable sheath protectors at multiple moments.

[0017] According to another aspect of an embodiment of the present application, a device for determining an aging time of a cable sheath protector is also provided, including: an acquisition module, used to obtain a first resistive current of the first cable sheath protector at a target time and a first voltage of the first cable sheath protector under normal operating conditions, wherein the target time is the time when an adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target time; a first determination module, used to calculate a first insulation resistance of the first cable sheath protector at the target time based on the first voltage and the first resistive current; a second determination module, used to match the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at the target time, wherein the relationship library stores a plurality of corresponding relationships between insulation resistances and aging times.

[0018] According to another aspect of an embodiment of the present application, a computer program product is also provided, which includes a stored computer program, wherein when the computer program is executed by a processor, the above-mentioned method for determining the aging time of the cable sheath protector is implemented.

[0019] According to another aspect of an embodiment of the present application, an electronic device is also provided, which includes: a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to execute the above-mentioned method for determining the aging time of the cable sheath protector through the computer program.

[0020] In an embodiment of the present application, the adjustable parallel resonator is electrically connected to the cable sheath protector through a frame, so that the insulation current of the cable sheath protector can be monitored without power failure, and the insulation resistance can be obtained using the normal operating voltage and insulation current of the first cable sheath protector. Compared with the traditional technical solution of measuring insulation resistance using a DC power supply, the present application solution enables live monitoring, so that the status of the cable sheath protector can be monitored in real time, and damage or failure of the cable sheath protector can be promptly checked, thereby solving the technical problem that the related technology can only monitor the insulation resistance of the cable sheath protector when the power is off, resulting in low efficiency and high cost in calculating the aging time of the cable sheath protector. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0022] Figure 1 It is a hardware structure block diagram of a computer terminal for implementing an optional method for determining the aging time of a cable sheath protector according to an embodiment of the present application;

[0023] Figure 2 It is a flow chart of an optional method for determining the aging time of a cable sheath protector according to an embodiment of the present application;

[0024] Figure 3 is a schematic diagram of a connection between an optional cable sheath protector and an adjustable parallel resonator according to an embodiment of the present application;

[0025] Figure 4 It is a schematic diagram of the connection between three adjustable parallel resonators and three cable sheath protectors controlled by an optional rotating structure according to an embodiment of the present application;

[0026] Figure 5 is a schematic structural diagram of an optional device for determining the aging time of a cable sheath protector according to an embodiment of the present application;

[0027] Figure 6 It is a schematic diagram of the structure of an optional electronic device according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0029] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, 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 "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0030] In addition, the relevant information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for display, data for analysis, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. For example, an interface is set up between this system and the relevant user or organization. Before obtaining relevant information, it is necessary to send an acquisition request to the aforementioned user or organization through the interface, and obtain relevant information after receiving the consent information fed back by the aforementioned user or organization.

[0031] In order to better understand the embodiments of the present application, the technical terms involved in the embodiments of the present application are explained as follows:

[0032] Cable sheath protector: a protective device used to protect the metal sheath of the cable sheath protector from various overvoltage hazards. It can effectively limit the induced voltage and fault overvoltage on the metal sheath (or metal sheath) of the cable sheath protector. It is usually installed between the metal sheath of the cable sheath protector and the ground, with no series gap. Under normal circumstances, the current flowing through the protector is very small, at the microampere level; when the sheath of the cable sheath protector is overvoltage, the protector resistance becomes smaller, the current increases, and the grace and on the sheath of the cable sheath protector are released to protect the normal and safe operation of the cable sheath protector.

[0033] Leakage current: refers to the abnormal current flowing out of electrical equipment or circuits due to insulation damage, leakage, etc., which is usually measured in milliamperes (mA). At present, the commonly used leakage current detection methods include: ground resistance method, residual current protector, insulation resistance measurement, thermal imaging detection method, etc.

[0034] Insulation aging: During long-term operation, the insulation of electrical equipment undergoes a series of physical changes such as softening or melting of solid dielectrics, volatilization of low molecular weight compounds and plasticizers, and chemical changes such as oxidation, electrolysis, ionization, and production of new substances, which cause its electrical, instrumental and other properties to gradually deteriorate, such as increased conductivity and dielectric loss, brittleness, cracking, etc. These phenomena are collectively referred to as insulation aging.

[0035] The basic principle of current transformer is to convert large current on the primary side into small current on the secondary side for measurement based on the principle of electromagnetic induction.

[0036] The Hall effect sensor device uses the Hall effect principle. When the magnetic flux generated by the primary current is concentrated in the magnetic circuit through the high-quality magnetic core, the Hall element is fixed in the air gap to detect the magnetic flux. The multi-turn coil wound on the magnetic core outputs a reverse compensation current to offset the magnetic flux generated by the primary, so that the magnetic flux in the magnetic circuit is always kept at zero. After processing by a special circuit, the output end of the sensor can accurately reflect the current change of the primary current.

[0037] Rogowski coil is a non-contact current sensor, mainly used in large alternating current applications, such as AC motor control, escalators, overhead lines and cables, etc.

[0038] Example 1

[0039] According to an embodiment of the present application, a method embodiment of a method for determining the aging time of a cable sheath protector is provided. It should be noted that the steps shown in the flowchart of the accompanying 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 can be executed in an order different from that shown here.

[0040] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Figure 1 The hardware structure block diagram of a computer terminal (or mobile device) for implementing a method for determining the aging time of a cable sheath protector is shown. Figure 1As shown, the computer terminal 10 (or mobile device 10) may include one or more (102a, 102b, ..., 102n are used to illustrate) processors 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA), a memory 104 for storing data, and a transmission device 106 for communication functions. In addition, it may also include: a display, an input / output interface (I / O interface), a universal serial bus (USB) port (which may be included as one of the ports of the BUS bus), a network interface, a power supply and / or a camera. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the above electronic device. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations shown.

[0041] It should be noted that the one or more processors 102 and / or other data processing circuits described above may generally be referred to herein as "data processing circuits". The data processing circuits may be embodied in whole or in part as software, hardware, firmware, or any other combination thereof. In addition, the data processing circuit may be a single independent processing module, or may be incorporated in whole or in part into any of the other components in the computer terminal 10 (or mobile device). As described in the embodiments of the present application, the data processing circuit acts as a processor control (e.g., selection of a variable resistor terminal path connected to an interface).

[0042] The memory 104 can be used to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the aging time determination method of the cable sheath protector in the embodiment of the present application. The processor 102 executes various functional applications and data processing by running the software programs and modules stored in the memory 104, that is, the aging time determination method of the cable sheath protector of the above-mentioned application is realized. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the computer terminal 10 via 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 combinations thereof.

[0043] The transmission device 106 is used to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the computer terminal 10. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, NIC), which can be connected to other network devices through a base station so as 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 wirelessly.

[0044] The display may be, for example, a touch screen liquid crystal display (LCD) that enables a user to interact with a user interface of the computer terminal 10 (or mobile device).

[0045] In the above operating environment, Figure 2 FIG. 1 is a flow chart of an optional method for determining the aging time of a cable sheath protector according to an embodiment of the present application, such as Figure 2 As shown, the method at least includes steps S202-S206, wherein:

[0046] Step S202, obtaining a first resistive current of the first cable sheath protector at a target time and a first voltage of the first cable sheath protector in a normal operating state.

[0047] In the technical solution provided in step S202, the first cable sheath protector is a single-ended grounded cable sheath protector at the measurement site; the target moment is the moment when the adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state; the first voltage is the terminal voltage value of the first cable sheath protector under normal operating conditions; the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target moment, which can be understood as: the resistive component contained in the leakage current passing through the protector when the first cable sheath protector is operating normally under parallel resonance conditions. Among them, the magnitude of the leakage current mainly depends on the design and manufacturing quality of the cable sheath protector, as well as the influence of the external environment, which can reflect the overall fault information of the insulation of the sheath of the cable sheath protector, that is, under the normal operating state of the cable sheath protector, the leakage current is very small, usually at the microampere level; however, once the sheath of the cable sheath protector is damaged or aged, the protector will quickly start working, and the charge discharged to the sheath of the cable sheath protector will also increase to protect the safe operation of the cable sheath protector, so the resistive component of the leakage current will also increase in response.

[0048] Step S204: Calculate a first insulation resistance of the first cable sheath protector at a target time according to the first resistive current and the first voltage.

[0049] In the technical solution provided in step S204, the first insulation resistance of the first cable sheath protector at the target time can be calculated based on the first voltage and the first resistive current and using Ohm's law, and the first insulation resistance can indirectly reflect the insulation condition of the sheath of the first cable sheath protector.

[0050] Step S206, matching the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at a target time.

[0051] In the technical solution provided in step S206, a relationship library of the corresponding relationship between multiple groups of insulation resistance and aging time is pre-constructed, and the first insulation resistance is matched with the relationship library to obtain the aging time corresponding to the first insulation resistance. The aging time is the first aging time of the sheath of the first cable sheath protector, also known as the insulation aging time.

[0052] The above method of this embodiment is further introduced below.

[0053] As an optional implementation, in the technical solution provided in the above step S202, the method may include:

[0054] Step S2021, in the process of adjusting the inductance value of the adjustable parallel resonator from the minimum value to the maximum value, obtaining the leakage current of the first cable sheath protector collected by using the leakage current monitoring device, determining the target time when the leakage current is at the trough position, and using the leakage current at the target time as the first resistive current of the first cable sheath protector;

[0055] Step S2022: obtaining a first voltage of the first cable sheath protector under normal operating conditions by using a voltage monitoring device.

[0056] In this embodiment, the inductance value of the adjustable parallel resonator is unidirectionally adjusted from the minimum inductance value to the increasing direction, and the leakage current monitoring device is used to monitor the change of the current at both ends of the first cable sheath protector, and the trough position where the leakage current monotonically increases after monotonically decreasing is taken as the resonance point (and the resonance point corresponds to the target time), and the leakage current at the resonance point is the first resistive current of the first cable sheath protector, and is recorded as I k At the same time, a voltage monitoring device (such as a voltmeter or a multimeter) is used to collect the first voltage at both ends of the first cable sheath protector in normal operation, which is recorded as U n .

[0057] It should be noted that a cable sheath is connected to a cable sheath protector, and a cable sheath protector is configured with an adjustable parallel resonator and a leakage current monitoring device for extracting and monitoring the leakage current of the corresponding cable sheath protector.

[0058] Specifically, the embodiments of the present application can be implemented according to Figure 3 The method shown establishes an electrical connection between the adjustable parallel resonator and the first cable sheath protector to extract the resistive component of the leakage current of the first cable sheath protector, such as Figure 3 As shown. Among them, 1 and 2 are two terminals of the adjustable parallel resonator connected to the first cable sheath protector, 3 is the reactor of the adjustable parallel resonator, 4 is the connecting plate of the first cable sheath protector, 5 is the main grounding wire in the grounding box of the first cable sheath protector, 6 is the first cable sheath protector, 7 is the connection between one end 1 of the adjustable parallel resonator connected to the first cable sheath protector and the connecting plate 4 of the first cable sheath protector, and 8 is a rotating structure for adjusting the connection state of the reactor.

[0059] Figure 3 One end 1 of the adjustable parallel resonator is connected to the connecting plate 4 of the first cable sheath protector by a non-fixed contact connection method, wherein the non-fixed contact connection method includes but is not limited to: a release type and a lap type. One end 2 of the adjustable parallel resonator is fixedly connected to the connection point of the main grounding wire 5 in the grounding box of the first cable sheath protector, and the rotating mechanism 8 of the adjustable parallel resonator is used to rotate 1 and 3 to realize the function of the adjustable parallel resonator being connected to the grounding box at will: when the rotating mechanism 8 makes the one end 1 of the adjustable parallel resonator electrically contact with the connecting plate 4 of the first cable sheath protector, the adjustable parallel resonator is connected in parallel with the protector; and when the rotating mechanism 8 makes the one end 1 of the adjustable parallel resonator electrically disconnected from the connecting plate 4, the adjustable parallel resonator is disconnected.

[0060] Optionally, the embodiment of the present application can control the rotating mechanism 8 by means of numerical control, and its specific implementation method may include: receiving an adjustable parallel resonator access control instruction initiated by the client, wherein the adjustable parallel resonator access control instruction carries a digital signal (such as a binary digital signal) for controlling the access state of the adjustable parallel resonator; when the digital signal is a valid value, controlling the adjustable parallel resonator to be electrically connected to the first cable sheath protector; when the digital signal is an invalid value, controlling the adjustable parallel resonator to be electrically disconnected from the first cable sheath protector.

[0061] For example, Figure 4 FIG. 1 is a schematic diagram of a connection between three adjustable parallel resonators and three cable sheath protectors controlled by an optional rotating structure according to an embodiment of the present application, such as Figure 4As shown, the three-phase cable sheath is connected to three cable sheath protectors, and each cable sheath protector is electrically connected to an adjustable parallel resonator, and the rotating structure of the adjustable parallel resonator can control its connection state. Figure 4 In the scenario shown, the digital signal can use a three-bit binary digital signal, where the valid value 1 is set to represent electrical connection, the invalid value 0 is set to represent disconnection of electrical connection, and each bit represents a different adjustable parallel resonator, such as 100 represents the first adjustable parallel resonator is electrically connected to the cable sheath protector, 010 represents the second adjustable parallel resonator is electrically connected to the cable sheath protector, and 001 represents the third adjustable parallel resonator is electrically connected to the cable sheath protector. It should be noted that the above-mentioned valid values ​​and invalid values ​​can be set according to the actual application scenario, and the embodiments of the present application do not impose specific restrictions on this.

[0062] In addition, in order to ensure that parallel resonance can occur, the value range of the reactance of the adjustable parallel resonator can be determined according to the maximum capacitance and minimum capacitance of various types of protectors (i.e., the second cable sheath protector) under the same cable voltage level monitored by the first cable sheath protector when operating normally, and the leakage current is less than the preset threshold condition (which is preferably set to 1mA, because the leakage current exceeding 1mA may cause electric shock risk.), so the expression of the value range of the reactance of the adjustable parallel resonator can be written as:

[0063]

[0064] Where, L represents the inductance of the adjustable parallel resonator, K max Indicates the upper limit factor of the reactor, K mim Indicates the lower limit coefficient of the reactor, C max It indicates the maximum capacitance value of multiple second cable sheath protectors under normal operation and leakage current less than the preset threshold value (i.e. the maximum capacitance value of all the multiple second cable sheath protectors under the same voltage level), C mim It represents the minimum capacitance value of multiple second cable sheath protectors under normal operating conditions and when the leakage current is less than a preset threshold value (i.e., the minimum capacitance value of all multiple second cable sheath protectors under the same voltage level), and ω represents the electrical angular velocity (its value can be 100π).

[0065] Optionally, the types of leakage current monitoring devices used include but are not limited to: current transformers, Hall effect sensors, Rogowski coils, etc. In actual application scenarios, factors such as measurement environment, measurement cost, and measurement accuracy requirements need to be considered when selecting leakage current monitoring devices.

[0066] Among them, the value range of the leakage current monitored by the leakage current monitoring device can be determined according to the maximum insulation resistance value and the minimum insulation resistance value of various types of protectors (i.e., the second cable sheath protector) under the same cable voltage level monitored by the first cable sheath protector when the leakage current is less than the preset threshold value (such as 1mA) during normal operation. Therefore, its expression can be written as:

[0067]

[0068] Among them, U min Indicates the minimum operating voltage at both ends of the first cable sheath protector when it is working normally, U max Indicates the maximum operating voltage at both ends of the first cable sheath protector when it is working normally, R max It indicates the maximum insulation resistance value of multiple second cable sheath protectors under normal operation and leakage current less than the preset threshold value (i.e. the maximum value of the resistance values ​​of all multiple second cable sheath protectors under the same voltage level). min It indicates the minimum insulation resistance value of multiple second cable sheath protectors under normal operating conditions and when the leakage current is less than a preset threshold value (i.e. the minimum value among the resistance values ​​of all multiple second cable sheath protectors under the same voltage level).

[0069] After the first resistive current I of the first cable sheath protector at the target time is obtained through the above step S202, k and the first voltage U n After that, the first insulation resistance of the first cable sheath protector at the target time can be obtained according to the following formula:

[0070]

[0071] As an optional implementation, in the technical solution provided in the above step S206, the relationship library can be established by the following method, including:

[0072] Step 1: Determine a plurality of second inductive sheath protectors of the same model as the first cable sheath protector.

[0073] Step 2: For each second cable sheath protector, obtain the second resistive current and the second aging time of the second cable sheath protector at multiple moments, as well as the second voltage of the second cable sheath protector under normal operating conditions, and calculate the second insulation resistance of the second cable sheath protector at multiple moments based on the multiple second resistive currents and the second voltages; determine the corresponding relationship between the second insulation resistance and the second aging time of the second cable sheath protector at multiple moments;

[0074] Step 3: construct a relationship library based on the corresponding relationship between the second insulation resistance and the second aging time of multiple second cable sheath protectors at multiple moments.

[0075] In this embodiment, firstly, a heating aging test is performed on the second cable sheath protector to obtain a plurality of second resistive currents and second aging times of the second cable sheath protector at a plurality of moments, and a second voltage at both ends of the second cable sheath protector under normal operation, wherein the above moments are also moments when the adjustable parallel resonator electrically connected to the second cable sheath protector is in a resonant state; then, the second insulation resistance of the second cable sheath protector at a plurality of moments is calculated based on the plurality of second resistive currents and second voltages, and the corresponding relationship between the second insulation resistance and the second aging time of the second cable sheath protector at a plurality of moments is determined; finally, the corresponding relationship between the second insulation resistance and the second aging time of each second cable sheath protector at each moment is recorded, and stored in a preset database to obtain the relationship library. The above-mentioned second inductive sheath protector and the first cable sheath protector are products of the same model generated by the same manufacturer, so they have the same product parameters, thereby avoiding the problem that the relationship library finally constructed cannot accurately obtain the first aging time corresponding to the first insulation resistance of the first cable sheath protector due to different analysis of product parameters.

[0076] Based on the scheme defined in the above steps S202 to S206, it can be known that in the embodiment, the adjustable parallel resonator is electrically connected to the cable sheath protector through a frame, so that the insulation current of the cable sheath protector can be monitored without power failure, and the insulation resistance can be obtained using the normal operating voltage and insulation current of the first cable sheath protector. Compared with the traditional method of using a DC power supply to measure the insulation resistance, the scheme of the present application enables live monitoring, so that the status of the cable sheath protector can be monitored in real time, and the damage or failure of the cable sheath protector can be promptly checked, thereby solving the technical problem that the related technology can only monitor the insulation resistance of the cable sheath protector when the power is off, resulting in low efficiency and high cost in calculating the aging time of the cable sheath protector.

[0077] Example 2

[0078] Based on the embodiment 1 of the present application, an embodiment of a device for determining the aging time of a cable sheath protector is also provided. When the device is running, the device for determining the aging time of the cable sheath protector of the above embodiment is executed. Figure 5 is a schematic structural diagram of an optional device for determining the aging time of a cable sheath protector according to an embodiment of the present application, such as Figure 5As shown, the aging time determination device of the cable sheath protector at least includes an acquisition module 52, a first determination module 54 and a second determination module 56, wherein:

[0079] An acquisition module 52 is used to acquire a first resistive current of the first cable sheath protector at a target time and a first voltage of the first cable sheath protector in a normal operating state, wherein the target time is the time when the adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target time;

[0080] A first determination module 54, configured to calculate a first insulation resistance of the first cable sheath protector at a target time according to the first voltage and the first resistive current;

[0081] The second determination module 56 is used to match the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at a target time, wherein the relationship library stores a plurality of corresponding relationships between insulation resistance and aging time.

[0082] It should be noted that the various modules in the aging time determination device of the above-mentioned cable sheath protector can be program modules (for example, a set of program instructions to implement a certain specific function) or hardware modules. For the latter, it can be expressed in the following forms, but is not limited to this: the expression form of each of the above-mentioned modules is a processor, or the functions of each of the above-mentioned modules are implemented by a processor.

[0083] Example 3

[0084] According to an embodiment of the present application, a computer program product is also provided, which includes a stored computer program, wherein when the computer program is executed by a processor, the method for determining the aging time of the cable sheath protector in Example 1 is implemented.

[0085] Optionally, the computer program executes the following steps: obtaining a first resistive current of the first cable sheath protector at a target moment and a first voltage of the first cable sheath protector under normal operating conditions, wherein the target moment is the moment when an adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target moment; calculating a first insulation resistance of the first cable sheath protector at the target moment based on the first resistive current and the first voltage; matching the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at the target moment, wherein the relationship library stores a plurality of sets of corresponding relationships between insulation resistance and aging time.

[0086] According to an embodiment of the present application, a processor is also provided, which is used to run a program, wherein the method for determining the aging time of the cable sheath protector in Example 1 is executed when the program is running.

[0087] Optionally, the following steps are executed when the program is running: obtaining a first resistive current of the first cable sheath protector at a target time and a first voltage of the first cable sheath protector under normal operating conditions, wherein the target time is the time when the adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target time; calculating a first insulation resistance of the first cable sheath protector at the target time based on the first resistive current and the first voltage; matching the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at the target time, wherein the relationship library stores a plurality of sets of corresponding relationships between insulation resistance and aging time.

[0088] According to an embodiment of the present application, an electronic device is also provided, wherein: Figure 6 is a schematic diagram of the structure of an optional electronic device according to an embodiment of the present application, such as Figure 6 As shown, the electronic device includes one or more processors; a memory for storing one or more programs, which, when the one or more programs are executed by the one or more processors, enables the one or more processors to run the programs, wherein the programs are configured to execute the aging time determination method of the cable sheath protector in the above-mentioned embodiment 1 when running.

[0089] Optionally, the processor is configured to execute the following steps through a computer program: obtaining a first resistive current of the first cable sheath protector at a target moment and a first voltage of the first cable sheath protector under normal operating conditions, wherein the target moment is the moment when the adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target moment; calculating a first insulation resistance of the first cable sheath protector at the target moment based on the first resistive current and the first voltage; matching the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at the target moment, wherein the relationship library stores a plurality of sets of corresponding relationships between insulation resistance and aging time.

[0090] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0091] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0092] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0093] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed over multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0094] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0095] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the relevant technology or all or part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of each embodiment method of the present application. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk, etc. Various media that can store program codes.

[0096] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for determining the aging time of a cable sheath protector, It is characterized in that Including: Among them, Obtaining a first resistive current of a first cable sheath protector at a target time and a first voltage of the first cable sheath protector in a normal operating state, wherein the target time is the time when an adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is the resistive component of the leakage current of the first cable sheath protector at the target time; Calculating a first insulation resistance of the first cable sheath protector at a target time according to the first resistive current and the first voltage; The first insulation resistance is matched with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at a target time, wherein the relationship library stores a plurality of sets of corresponding relationships between insulation resistance and aging time.

2. The method according to claim 1, It is characterized in that Obtaining a first resistive current of the first cable sheath protector at a target time and a first voltage of the first cable sheath protector in a normal operating state, including: In the process of adjusting the inductance value of the adjustable parallel resonator from the minimum value to the maximum value, the leakage current of the first cable sheath protector is collected by using a leakage current monitoring device, a target time when the leakage current is at a trough position is determined, and the leakage current at the target time is used as the first resistive current of the first cable sheath protector; A first voltage of the first cable sheath protector under normal operating conditions is acquired by using a voltage monitoring device.

3. The method according to claim 2, It is characterized in that The adjustable parallel resonator comprises: a reactor and a rotating structure for adjusting the connection state of the reactor, wherein: Receiving an adjustable parallel resonator access control instruction initiated by a client, wherein the adjustable parallel resonator access control instruction carries a digital signal for controlling an access state of the adjustable parallel resonator; When the digital signal is a valid value, controlling the adjustable parallel resonator to be electrically connected to the first cable sheath protector; When the digital signal has an invalid value, the adjustable parallel resonator is controlled to be electrically disconnected from the first cable sheath protector.

4. The method according to claim 2, It is characterized in that The expression of the value range of the inductance value of the adjustable parallel resonator is as follows: Wherein, L represents the inductance value of the adjustable parallel resonator, K max Indicates the upper limit factor of the reactor, K mim Indicates the lower limit coefficient of the reactor, C max Indicates the maximum capacitance value of multiple second cable sheath protectors under normal operation and leakage current less than the preset threshold, C mim It represents the minimum capacitance value of multiple second cable sheath protectors under normal operating conditions and when the leakage current is less than a preset threshold value. The second cable sheath protectors are of the same model as the first cable sheath protectors. ω represents the electrical angular velocity.

5. The method according to claim 2, It is characterized in that The type of the leakage current monitoring device includes at least one of the following: a current transformer, a Hall effect sensor device, and a Rogowski coil.

6. The method according to claim 2, It is characterized in that The expression of the value range of the leakage current monitored by the leakage current monitoring device is as follows: Among them, U min Indicates the minimum operating voltage at both ends of the first cable sheath protector when it is working normally, U max Indicates the maximum operating voltage at both ends of the first cable sheath protector when it is working normally, R max It indicates the maximum insulation resistance value of multiple second cable sheath protectors under normal operation and leakage current less than the preset threshold. min It represents the minimum insulation resistance value of multiple second cable sheath protectors under normal operating conditions and when the leakage current is less than a preset threshold value. The second cable sheath protectors are of the same model as the first cable sheath protectors.

7. The method according to claim 1, It is characterized in that The construction process of the relationship library includes: Determining a plurality of second inductive sheath protectors of the same model as the first cable sheath protector; For each of the second cable sheath protectors, obtain the second resistive current and the second aging time of the second cable sheath protector at multiple moments, as well as the second voltage of the second cable sheath protector in a normal operating state, and calculate the second insulation resistance of the second cable sheath protector at multiple moments based on the multiple second resistive currents and the second voltages; determine the corresponding relationship between the second insulation resistance and the second aging time of the second cable sheath protector at multiple moments; The relationship library is constructed by the corresponding relationships between the second insulation resistances and the second aging times of a plurality of the second cable sheath protectors at a plurality of moments.

8. A device for determining the aging time of a cable sheath protector, It is characterized in that include: An acquisition module, used for acquiring a first resistive current of a first cable sheath protector at a target moment and a first voltage of the first cable sheath protector in a normal operating state, wherein the target moment is a moment when an adjustable parallel resonator electrically connected to the first cable sheath protector is in a resonant state, and the first resistive current is a resistive component of a leakage current of the first cable sheath protector at the target moment; A first determination module, configured to calculate a first insulation resistance of the first cable sheath protector at a target time according to the first voltage and the first resistive current; The second determination module is used to match the first insulation resistance with a preset relationship library to obtain a first aging time of the sheath of the first cable sheath protector at a target time, wherein the relationship library stores a plurality of corresponding relationships between insulation resistance and aging time.

9. A computer program product, It is characterized in that include: A computer program, wherein when the computer program is executed by a processor, the method for determining the aging time of a cable sheath protector according to any one of claims 1 to 7 is implemented.

10. An electronic device, It is characterized in that include: A memory and a processor, wherein the processor is used to run a program stored in the memory, wherein the program, when running, executes the aging time determination method of the cable sheath protector according to any one of claims 1 to 7.

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