High-voltage cable terminal state monitoring device and high-voltage cable terminal

Abstract

The utility model discloses a high-voltage cable terminal state monitoring device and a high-voltage cable terminal. The high-voltage cable terminal state monitoring device is used for detecting the state of insulating oil in a high-voltage cable terminal and comprises a shell, an energy storage unit, a data processing unit, a laser ranging sensor and a gas sensor, and the energy storage unit is arranged in the shell; the data processing unit is arranged in the shell and is electrically connected with the energy storage unit; the laser distance measuring sensor is connected to the shell, at least part of the laser distance measuring sensor is exposed out of the working face of the shell, the laser distance measuring sensor is used for emitting laser and measuring the distance between the working face and the insulating oil top face through the laser, and the laser distance measuring sensor is electrically connected with the data processing unit; the gas sensor is connected to the shell, at least part of the gas sensor is exposed out of one face of the shell, the gas sensor is used for detecting gas generated by the insulating oil, and the gas sensor is electrically connected with the data processing unit.

Description

Technical Field

[0001] This utility model relates to the field of power transmission line condition monitoring, and in particular to a high-voltage cable terminal condition monitoring device and a high-voltage cable terminal. Background Technology

[0002] High-voltage cable terminals, as conversion components between cable lines and overhead lines, are a very important part of the entire power transmission line.

[0003] Due to the relatively enclosed structure and location at the end of the line, monitoring the operational status of high-voltage cable terminals is less common compared to cable joints. Monitoring primarily focuses on grounding current, induced voltage, partial discharge monitoring, and external infrared thermography. Some manufacturers also monitor the insulating oil level inside the terminal to detect leaks. Insulating oil level monitoring mainly employs pressure conversion or ultrasonic methods. Pressure conversion is affected by the temperature of the cable terminal during operation. Because the terminal has a sealed structure, the internal pressure varies at different temperatures, leading to greater errors in oil level calculation and affecting measurement accuracy. Ultrasonic methods suffer from significant blind spots due to the ultrasonic sensor's detection principle, and temperature also affects measurement accuracy, requiring temperature compensation circuits, which presents some inconvenience in use.

[0004] The insulating oil inside high-voltage cable terminals decomposes and deteriorates after being subjected to high-temperature aging or discharge aging, resulting in a significant increase in the content of certain gases. However, since high-voltage cable terminals are mostly installed on high-voltage terminal towers, the installation position is relatively high and the corresponding equipment is difficult to install. In addition, to ensure their sealing performance, it is not possible to use oil chromatography analysis methods similar to those used for transformers to analyze the gas composition. Therefore, there is currently no monitoring method to monitor these characteristic gases. Nevertheless, effective monitoring of the content of these characteristic gases can effectively reflect the state of the insulating oil inside the high-voltage cable terminal and understand the operating status of the high-voltage cable terminal. Utility Model Content

[0005] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a high-voltage cable terminal condition monitoring device that can accurately detect the condition of the insulating oil, thereby improving its reliability.

[0006] According to a first aspect of the present invention, a high-voltage cable terminal condition monitoring device is used to detect the condition of insulating oil inside a high-voltage cable terminal, including:

[0007] case;

[0008] The energy storage unit is located inside the housing;

[0009] A data processing unit is arranged in the shell and electrically connected with the energy storage unit.

[0010] A laser ranging sensor is connected with the shell, at least part of the laser ranging sensor is exposed on the working surface of the shell, and the laser ranging sensor is used for emitting laser and measuring the distance between the working surface and the top surface of the insulating oil by laser.

[0011] A gas sensor is connected with the shell, at least part of the gas sensor is exposed on a surface of the shell, and the gas sensor is used for detecting the gas generated by the insulating oil, and the gas sensor is electrically connected with the data processing unit.

[0012] According to the high-voltage cable terminal state monitoring device provided by the utility model, at least the following beneficial effects are achieved:

[0013] 1. The laser ranging sensor is used for detecting the distance between the working surface and the top surface of the insulating oil, when the height of the insulating oil decreases, the distance between the working surface and the top surface of the insulating oil increases, and according to the speed of the decrease of the insulating oil, it is determined whether the insulating oil leaks, thereby improving the use reliability of the cable terminal.

[0014] 2. The gas sensor is used for detecting the gas generated by the insulating oil, and according to the concentration of the gas, it is determined whether the insulating oil is decomposed, thereby knowing the quality of the insulating oil in time, and improving the use reliability of the cable terminal.

[0015] According to some embodiments of the utility model, the gas sensor is used for detecting hydrogen and / or acetylene gas.

[0016] According to some embodiments of the utility model, the gas sensor is a palladium alloy nanometer film hydrogen sensor and / or an infrared acetylene sensor.

[0017] According to some embodiments of the utility model, the shell is annular.

[0018] According to some embodiments of the utility model, the energy storage unit is semicircular, the data processing unit is semicircular, the data processing unit is connected with the energy storage unit to form a ring, and the energy storage unit is arranged below the data processing unit and the energy storage unit.

[0019] According to some embodiments of the utility model, the energy storage unit comprises a power taking transformer and an energy storage element electrically connected with the power taking transformer.

[0020] According to some embodiments of the utility model, the data processing unit includes a substrate, a first data processing circuit and a first LORA communication module which are all connected to the substrate, and the first LORA communication module is electrically connected to the first data processing circuit.

[0021] According to the high-voltage cable terminal of the second aspect of the utility model, at least the following beneficial effects are achieved:

[0022] The main body has an insulating chamber and insulating oil arranged in the insulating chamber.

[0023] The high-voltage cable terminal state monitoring device of the first aspect of the utility model is arranged in the insulating chamber and located at the top of the insulating chamber, and the working surface is arranged opposite to the top surface of the insulating oil.

[0024] The laser ranging sensor is configured to detect the distance between the working surface and the top surface of the insulating oil.

[0025] According to the high-voltage cable terminal of the second aspect of the utility model, at least the following beneficial effects are achieved:

[0026] According to some embodiments of the utility model, the high-voltage cable terminal further comprises a data acquisition device connected to the main body and located at the bottom outside the main body, the data acquisition device comprises a second data processing circuit, a second LORA communication module, a 4G communication module, and an Ethernet communication module, the second LORA communication module is communicatively connected to the data processing unit, and is communicatively connected to a data terminal through the 4G communication module or the Ethernet communication module.

[0027] According to some embodiments of the utility model, the high-voltage cable terminal further comprises a connecting piece arranged in the insulating chamber and a sealing flange arranged at the top of the insulating chamber, the connecting piece is sealingly arranged in the sealing flange, the shell surrounds the connecting piece and is detachably connected to the sealing flange.

[0028] Additional aspects and advantages of the utility model will be partially given in the following description, partially will become obvious from the following description, or will be understood through the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0029] The utility model will be further described below in combination with the drawings and embodiments, wherein:

[0030] Figure 1A structure schematic view of the high-voltage cable terminal state monitoring device of an embodiment of the present application;

[0031] Figure 2 A sectional view of the high-voltage cable terminal state monitoring device of an embodiment of the present application;

[0032] Figure 3 A structure schematic view of the high-voltage cable terminal of an embodiment of the present application;

[0033] Figure 4 A sectional view of the high-voltage cable terminal of an embodiment of the present application.

[0034] Reference signs:

[0035] The shell 100; the upper half shell 110; the lower half shell 120;

[0036] The energy storage unit 200; the energy extraction mutual inductor 210; the energy storage element 220;

[0037] The data processing unit 300;

[0038] The laser ranging sensor 400;

[0039] The gas sensor 600;

[0040] The main body 700; the insulating chamber 710; the insulating oil 720; the connecting piece 730; the sealing flange 740;

[0041] The data acquisition device 800. DETAILED DESCRIPTION

[0042] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary, only for explaining the present application, and cannot be understood as limiting the present application.

[0043] In the description of the present application, it should be understood that the orientation description, such as the orientation or position relationship of the indications such as up and down, is based on the orientation or position relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0044] In the description of the utility model, several refer to one and more than one, and multiple refer to two and more than two. If the first and second are described, it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.

[0045] In the description of the utility model, unless otherwise explicitly limited, the words such as setting, installation, connection, etc. should be understood broadly, and the person skilled in the art can determine the specific meaning of the above words in the utility model in combination with the specific content of the technical scheme.

[0046] Referring to Figures 1 to 4 The utility model discloses a high -tension cable terminal state monitoring devices for detecting the state of the insulating oil 720 in high -tension cable terminal, include: casing 100, energy storage unit 200, data processing unit 300, laser ranging sensor 400 and gas sensor 600.

[0047] In the embodiment, the casing 100 is made of ABS material resistant to high temperature, comprising upper half shell 110 and lower half shell 120, and the mounting chamber is formed by assembling the upper half shell 110 and the lower half shell 120. The connection mode of the upper half shell 110 and the lower half shell 120 includes but is not limited to interference joint, buckle connection, bolt locking and other detachable connection modes. Of course, under the premise of not considering subsequent maintenance, the upper half shell 110 and the lower half shell 120 can also be connected in an integrated manner, for example, bonded as a whole. The casing 100 also has a bolt hole, and the casing 100 can be locked to the high-voltage cable terminal by the bolt passing through the bolt hole. The bolt hole can be connected to the upper half shell 110 and the lower half shell 120, or it can be provided in one of the upper half shell 110 and the lower half shell 120. The lower surface of the lower half shell 120 forms a working surface.

[0048] The energy storage unit 200 is arranged in the casing 100, and the energy storage unit 200 is used for power supply for the data processing unit 300, the laser ranging sensor 400 and the gas sensor 600. In the embodiment, the energy storage unit 200 can supply power for one or more of AC 220V power supply, CT induction power supply, solar energy and battery.

[0049] The data processing unit 300 is arranged in the casing 100 and electrically connected with the energy storage unit 200. The data processing unit 300 is used for collecting and storing measurement data, and can be timely forwarded to the outside world, so that the outside personnel can timely understand the state of the insulating oil 720 in the high-voltage cable terminal, and can make corresponding treatment according to the actual situation.

[0050] The laser rangefinder 400 is connected to the housing 100. At least a portion of the laser rangefinder 400 is exposed on the working surface of the housing 100 and is used to emit a laser and measure the distance between the working surface and the top surface of the insulating oil 720. The laser rangefinder 400 is electrically connected to the data processing unit 300.

[0051] Specifically, the laser rangefinder 400 employs the Time-of-Flight (TOF) principle. It calculates the distance between the sensor and the insulating oil 720-air interface by measuring the difference between the emitted and received infrared laser light at a high frequency. Furthermore, TOF-based rangefinders offer advantages such as long detection distance, high measurement accuracy, and strong low-light detection capabilities, making them suitable for distance measurement in low-light environments inside high-voltage cable terminals, thus avoiding the drawback of poor measurement performance under strong light. The laser rangefinder 400 is smaller and thinner than ultrasonic sensors, with a smaller blind zone, effectively reducing the overall height of the monitoring device and minimizing the detection blind zone. This prevents the insulating oil 720 from rising into the detection blind zone due to thermal expansion and contraction.

[0052] In this embodiment, insulating oil 720 is stored in a fixed-shape insulating chamber 710 within the high-voltage cable terminal. After the laser rangefinder 400 is installed in the insulating chamber 710, the height from the working surface to the bottom of the insulating chamber 710 is known. When the laser rangefinder 400 emits a laser beam that illuminates the top surface of the insulating oil 720, the laser is reflected. By calculating the time difference between emission and reflection, the distance from the working surface to the top surface of the insulating oil 720 can be obtained. The height of the insulating oil 720 can be obtained by subtracting the distance from the bottom of the insulating chamber 710 to the height of the top surface of the insulating oil 720, thus determining the height of the insulating oil 720 within the insulating chamber 710. Simultaneously, the laser rangefinder 400 detects the distance between the working surface and the top surface of the insulating oil 720. As the height of the insulating oil 720 decreases, the distance between the working surface and the top surface of the insulating oil 720 increases. Based on the rate of decrease of the insulating oil 720, it can be determined whether there is a leakage in the insulating oil 720, thereby improving the reliability of the cable terminal.

[0053] A gas sensor 600 is connected to the housing 100, with at least a portion exposed on one side of the housing 100. The gas sensor 600 is used to detect gases generated by the insulating oil 720 and is electrically connected to the data processing unit 300. It should be noted that the insulating oil 720 will decompose and generate some gas after electrical aging, thermal aging, or a combination of both. Therefore, by detecting the gas generated by the insulating oil 720 using the gas sensor 600, the concentration of the gas can be used to determine whether the insulating oil 720 has deteriorated or decomposed, thus allowing for timely understanding of the quality of the insulating oil 720 and improving the reliability of the cable terminal. The gas sensor 600 is also exposed on the working surface of the housing 100. In other embodiments, the gas sensor 600 may also be exposed on the top or side surface of the housing 100.

[0054] In some specific embodiments of this invention, the gas sensor 600 is used to detect hydrogen and / or acetylene gas. The gas sensor 600 is a palladium alloy nanofilm hydrogen sensor and / or an infrared acetylene sensor.

[0055] It should be noted that after electrical aging, thermal aging, or a combination of both, the content of hydrogen and acetylene in the gases produced by the decomposition of insulating oil 720 varies considerably. Hydrogen and / or acetylene are characteristic gases that can reflect the aging state of insulating oil 720. For example, in this embodiment, both hydrogen and acetylene are used as characteristic gases, and the gas sensor 600 is a palladium alloy nanofilm hydrogen sensor and / or an infrared acetylene sensor. By using palladium alloy nanofilm hydrogen sensor and infrared acetylene sensor, effective monitoring of the two characteristic gases can be achieved. At the same time, compared with conventional electrochemical sensors, since they do not require electrolytes and catalytic combustion, they have a longer service life and do not need to be replaced regularly. They also avoid leakage and other situations that may harm the operation of the terminal.

[0056] Specifically, the hydrogen sensor employs the palladium alloy nanofilm principle, utilizing the catalytic decomposition of the gas by the metal film to cause a change in the conductivity of the alloy film, thereby measuring the hydrogen concentration. Compared to hydrogen sensors using electrochemical or catalytic combustion methods, it eliminates the need for an electrolyte, preventing electrolyte drying and leakage, resulting in a longer lifespan and less maintenance. Furthermore, due to its thin-film principle, the sensor can directly contact insulating oil 720, exhibiting good adaptability to silicone oil vapors that may be present in high-voltage cable terminals and demonstrating excellent resistance to silicon poisoning. The acetylene sensor utilizes the NDIR (non-dispersive infrared) principle, determining the concentration of the gas by measuring the intensity of infrared light entering the infrared detector after the infrared light source passes through the gas being measured. Compared to conventional catalytic combustion acetylene sensors, the infrared acetylene sensor effectively avoids the reduction in activity and sensitivity caused by the catalyst reacting with the gas being measured. Because the NDIR acetylene sensor uses an optical principle, it does not require oxygen to participate in the redox reaction, avoiding the zero-point rise caused by reaction products on the catalytic bead surface. Based on these advantages, it exhibits excellent resistance to poisoning and stability.

[0057] Compared to traditional electrochemical or catalytic combustion sensors, these two types of gas sensors use physical methods, such as conductivity and infrared absorption, to detect the concentration of the gas being measured, rather than chemical reactions. This eliminates the need for electrolytes or catalysts to react with the gas and thus extends the overall lifespan of the monitoring device and further prolongs its maintenance cycle.

[0058] In this embodiment, when abnormal discharge or heating occurs inside the cable terminal, causing electrical aging, thermal aging, or electrothermal aging of the insulating oil 720, hydrogen and acetylene are generated through decomposition inside the terminal. Because the cable terminal is a sealed structure, the gas will continuously accumulate inside the terminal. Furthermore, since the density and molecular mass of hydrogen and acetylene are both less than that of air, they will rise to the vicinity of the monitoring device at the top of the insulating chamber 710, thereby achieving effective monitoring of changes in hydrogen and acetylene content.

[0059] Reference Figure 1 and Figure 2 As shown, in some specific embodiments of this utility model, the housing 100 is annular. The energy storage unit 200 is semi-annular, and the data processing unit 300 is semi-annular. The data processing unit 300 and the energy storage unit 200 are connected to form an annular structure, and the energy storage unit 200 is annularly disposed below the data processing unit 300 and the energy storage unit 200. The energy storage unit 200 includes an energy harvesting transformer 210 and an energy storage element 220 electrically connected to the energy harvesting transformer 210.

[0060] In this embodiment, the housing 100 is annular and surrounds the connector 730 within the high-voltage cable terminal. The connector 730 is used to allow current to pass through. The energy storage unit 200 utilizes current transformer (CT) induction power extraction. Specifically, CT induction power extraction refers to using a current transformer to induce electrical energy from the transmission line and, through a series of transformations and controls, converting this electrical energy into a controllable and stable output required for the target application. Its theoretical basis stems from Faraday's law of electromagnetic induction, which states that a change in magnetic flux will cause a change in current. When the tested wire passes through the primary winding of the CT, it generates a magnetic field around the magnetic core. This magnetic field is transmitted to the secondary winding. Since the number of windings in the secondary winding is much greater than that in the primary winding, the generated voltage is much smaller than the original current. The secondary circuit of the CT is dummy-connected to the input circuit of devices such as relays, providing a current signal to the input circuit.

[0061] Specifically, the energy storage unit 200 converts the current input to the energy storage element 220 through the energy harvesting transformer 210 to charge the energy storage element 220. The energy storage element 220 can supply power to various sensors for a long time without the need for an external power supply, making it more reliable.

[0062] Reference Figure 2 As shown, in some specific embodiments of this utility model, the data processing unit 300 includes a substrate, a first data processing circuit and a first LORA communication module, all connected to the substrate, and the first LORA communication module is electrically connected to the first data processing circuit.

[0063] In this embodiment, the first data processing circuit summarizes the real-time monitoring data from the laser rangefinder 400 and the gas sensor 600, converts it into the required data message format, and transmits it wirelessly to the data concentrator through the first LORA communication module to achieve data forwarding. This allows the user to understand the status of the insulating oil 720 inside the high-voltage cable terminal in real time, thereby improving the reliability of the high-voltage cable terminal.

[0064] Reference Figure 3 and Figure 4As shown, a second aspect of this utility model provides a high-voltage cable terminal, comprising: a main body 700 and a high-voltage cable terminal status monitoring device according to the first aspect embodiment. The main body 700 has an insulating chamber 710 and insulating oil 720 disposed within the insulating chamber 710; the high-voltage cable terminal status monitoring device according to the first aspect embodiment is disposed within the insulating chamber 710 and located at the top of the insulating chamber 710, with its working surface facing the top surface of the insulating oil 720; a laser ranging sensor 400 is configured to detect the distance between the working surface and the top surface of the insulating oil 720. It is worth understanding that by using the high-voltage cable terminal status monitoring device according to the first aspect embodiment, the high-voltage cable terminal can promptly understand the height and quality of the insulating oil 720 within the insulating chamber 710, ensuring that the insulating oil 720 is in a normal working state and improving the reliability of the high-voltage cable terminal.

[0065] Reference Figure 3 and Figure 4 As shown, in some specific embodiments of this utility model, the high-voltage cable terminal further includes: a data acquisition device 800, which is connected to the main body 700 and located at the bottom outside the main body 700. The data acquisition device 800 includes a second data processing circuit, a second LoRa communication module, a 4G communication module, and an Ethernet communication module. The second LoRa communication module is communicatively connected to the data processing unit 300 and is communicatively connected to the data terminal through the 4G communication module or the Ethernet communication module.

[0066] In this embodiment, the data acquisition device 800 wirelessly communicates with the first LORA communication module of the data processing unit 300 through the second LORA communication module to collect real-time monitoring data from the laser rangefinder 400 and the gas sensor 600 in the data processing unit 300, and summarizes and processes the data from each data acquisition device, converts it into the corresponding message format, and sends it to the data terminal, such as the monitoring platform, in the form of 4G or Ethernet.

[0067] Reference Figure 4 As shown, in some specific embodiments of this utility model, the high-voltage cable terminal further includes: a connector 730 passing through the insulating chamber 710 and a sealing flange 740 disposed on the top of the insulating chamber 710. The connector 730 is sealed through the sealing flange 740, and the housing 100 surrounds the connector 730 and is detachably connected to the sealing flange 740.

[0068] In this embodiment, the housing 100 is bolted to the sealing flange 740, making it easier to disassemble and separate the high-voltage cable terminal status monitoring device from the high-voltage cable terminal, facilitating maintenance. In other embodiments, the housing 100 can also be connected to the sealing flange 740 via snap-fit ​​or other connection methods.

[0069] The embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present utility model.

Claims

1. A high-voltage cable termination condition monitoring apparatus for detecting a condition of insulating oil within a high-voltage cable termination, characterized by, The device comprises: a housing; a power storage unit arranged in the housing; a data processing unit arranged in the housing and electrically connected to the power storage unit; a laser ranging sensor connected to the housing, at least part of the laser ranging sensor being exposed to a working surface of the housing, and configured to emit laser and measure the distance between the working surface and the top surface of the insulating oil by laser, the laser ranging sensor being electrically connected to the data processing unit; a gas sensor connected to the housing, at least part of the gas sensor being exposed to a surface of the housing, and configured to detect the gas generated by the insulating oil, the gas sensor being electrically connected to the data processing unit.

2. A high voltage cable termination condition monitoring apparatus according to claim 1, characterised in that: The gas sensor is configured to detect hydrogen and / or acetylene gas.

3. A high voltage cable termination condition monitoring apparatus according to claim 2, characterised in that: The gas sensor is a palladium alloy nanometer film hydrogen sensor and / or an infrared acetylene sensor.

4. The high voltage cable termination condition monitoring apparatus of claim 1, wherein: The housing is annular.

5. A high voltage cable termination condition monitoring apparatus according to claim 4, characterised in that: The power storage unit is semi-annular, the data processing unit is semi-annular, the data processing unit is connected to the power storage unit to form an annular shape, and the power storage unit is arranged below the data processing unit in an annular shape.

6. The high voltage cable termination condition monitoring apparatus of claim 1, wherein: The power storage unit comprises a power extraction transformer and a power storage element electrically connected to the power extraction transformer.

7. The high voltage cable termination condition monitoring apparatus of claim 1, wherein: The data processing unit comprises a substrate, a first data processing circuit and a first LORA communication module connected to the substrate, and the first LORA communication module is electrically connected to the first data processing circuit.

8. A high voltage cable termination, characterized by The device comprises: a main body having an insulating chamber and an insulating oil arranged in the insulating chamber; the high-voltage cable terminal state monitoring device according to any one of claims 1 to 7 is arranged in the insulating chamber and located at the top of the insulating chamber, the working surface is arranged opposite to the top surface of the insulating oil; the laser ranging sensor is configured to detect the distance between the working surface and the top surface of the insulating oil.

9. A high voltage cable termination according to claim 8, characterised in that The high-voltage cable terminal further comprises a data acquisition device connected to the main body and located at the bottom outside the main body, the data acquisition device comprising a second data processing circuit, a second LORA communication module, a 4G communication module and an Ethernet communication module, the second LORA communication module being communicatively connected to the data processing unit and being communicatively connected to the data terminal through the 4G communication module or the Ethernet communication module.

10. A high voltage cable termination according to claim 8, characterised in that The high-voltage cable terminal further comprises a connecting piece penetrating the insulating chamber and a sealing flange arranged at the top of the insulating chamber, the connecting piece is sealed to penetrate the sealing flange, the housing surrounds the connecting piece and is detachably connected to the sealing flange.

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