A monitoring device for a current transformer

Abstract

The utility model provides a monitoring device for current transformer, including oil conservator and porcelain sleeve pipe connected with bottom, still include: oil outlet, install in the lower middle part of the front end of porcelain sleeve pipe, detection pipe is installed in the front of oil outlet, and detection pipe is linked with oil outlet, porcelain sleeve pipe intercommunication, pressure slide post is slid in the inside rear side of detection pipe, and the middle part of pressure slide post is installed with heat insulation inner tube, electric current sensing assembly is installed in the inside of pressure slide post for sensing the partial discharge current released in oil conservator and porcelain sleeve pipe, hollow cavity post is fixedly installed in the inside front side of detection pipe, when using, can judge oil pressure change of current transformer is caused by oil leakage or oil temperature abnormal reason through the current change formed by test assembly and expansion assembly, simultaneously, can not only protect test assembly by using electric current sensing assembly, but also can monitor the partial discharge phenomenon in current transformer.

Description

Technical Field

[0001] This invention relates to the field of current transformers, and more specifically, to a monitoring device for current transformers. Background Technology

[0002] In power systems, current transformers serve the functions of current conversion and electrical isolation, and are widely used in relay protection, electricity metering, and other fields. Their measurement accuracy and operational reliability are prerequisites for the safe operation of power systems. Outdoor current transformers operate in harsh environments and are more prone to failure.

[0003] During the investigation into the cause of the explosion accident of the oil-immersed inverted current transformer, it was found that if the current transformer is severely short of oil or leaks oil, its insulation strength will be reduced, which will easily lead to insulation breakdown. This will not only cause damage to the current transformer or even an explosion, but may also allow high voltage current to enter the secondary side, posing a major threat to the safety of secondary equipment and operators.

[0004] Existing technical solutions typically use oil pressure detection to monitor for oil leaks. However, the oil pressure inside a sealed current transformer can fluctuate due to various factors. Excessive sensitivity in oil pressure detection can lead to frequent alarms, while insufficient sensitivity can make it difficult to detect faults in a timely manner. In practical use, two types of faults that are difficult to distinguish are oil pressure changes caused by oil leaks and oil pressure changes caused by temperature increases.

[0005] Therefore, how to distinguish between oil pressure changes caused by oil leakage and oil pressure changes caused by temperature rise is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] The purpose of this invention is to provide a monitoring device for current transformers, which solves the problem of inconvenient and effective identification of the cause of abnormal oil pressure in current transformer monitoring, thereby avoiding unnecessary frequent inspections and maintenance. The specific technical solution is as follows:

[0007] The rheostat has two sliding resistance blocks, a first resistance block and a second resistance block. The first resistance block is connected to a hydraulic sliding device via a mechanical connection. The hydraulic sliding device is connected to a hydraulic sealing device via a pipe. The hydraulic sliding device is a sliding component installed inside the pipe, and it is maintained in balance with the liquid pressure by a spring. The sliding component will not move if the pressure in the sealing reservoir remains unchanged. If the sealing reservoir leaks oil, the sliding component will move, thereby causing the connected first resistance block to move.

[0008] The second resistive block is thermally connected to the sealed liquid storage device via a temperature-moving device. This thermal connection refers to the transfer of heat to the temperature-moving device through heat transfer, heat radiation, or other means. The temperature-moving device contains a thermistor, which changes in volume, length, and shape in response to changes in temperature, thereby displacing the second resistive block. When the temperature of the liquid in the sealed liquid storage device rises, heat is transferred to the temperature-moving device, causing the thermistor to displace and move the second resistive block.

[0009] When an oil leak occurs in the sealed liquid storage device, the first resistive block moves away from the second resistive block, increasing the resistance of the rheostat. When the oil temperature in the sealed liquid storage device rises, the second resistive block moves closer to the first resistive block, causing the rheostat's resistance to increase. By measuring the direction of the resistance change, the type of accident can be determined. This solves the problem that existing technologies cannot distinguish the type of accident.

[0010] The beneficial effects of this invention are as follows:

[0011] 1. The detection tube can sensitively respond to abnormal oil pressure in the oil tank and porcelain sleeve by the displacement change of the internal pressure slide. When the oil pressure decreases, the movement of the pressure slide, traction sleeve and sliding plate increases the resistance value between the first and second resistance blocks on the rheostat, so that the current flowing through it decreases. This current is captured by the ammeter and transmitted to the end cover alarm, realizing an immediate alarm and effectively reminding maintenance personnel to pay attention to possible oil leakage problems.

[0012] 2. When the temperature inside the oil conservator and the porcelain bushing is abnormal, the heat-conducting wire transfers heat to the expansion bladder. Through the thermal expansion and contraction characteristics of the internal inert gas, the second resistance block is pushed to move on the rheostat, and the distance between it and the first resistance block decreases, which increases the current flowing through it. This current is captured by the ammeter and transmitted to the end cover alarm, effectively identifying abnormal oil pressure caused by abnormal temperature rather than oil leakage. Attached Figure Description

[0013] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0014] Figure 2 For the present invention Figure 1 Enlarged diagram of point A.

[0015] Figure 3 This is a schematic diagram of the internal structure of the detection tube of the present invention.

[0016] Figure 4 This is a side view of the detection tube of the present invention.

[0017] Figure 5 This is a schematic diagram of the internal structure of the hollow cavity column of the present invention.

[0018] Figure 6This is a schematic diagram of the opening sleeve column position structure of the present invention.

[0019] Figure 7 This is a schematic diagram of the front structure of the hollow cavity column of the present invention.

[0020] Figure 8 This is a schematic diagram of the test component structure of the present invention.

[0021] Figure 9 This is a schematic diagram of the expansion component structure of the present invention.

[0022] Figure 10 This is a schematic diagram of the internal structure of the telescopic bladder of the present invention.

[0023] Figure 11 This is a schematic diagram of the inductive component structure of the present invention.

[0024] Figure 12 For the present invention Figure 11 Enlarged diagram of point B.

[0025] Figure 13 This is a schematic diagram of the heat-insulating inner tube structure of the present invention.

[0026] Figure 14 This is a schematic diagram illustrating the principle of hydrogen measurement using the catalytic decomposition of gases by a metal thin film, as described in this invention.

[0027] The attached diagram is labeled as follows: 1. Oil tank; 2. Porcelain sleeve; 3. Oil outlet; 4. Detection tube; 5. Pressure slide; 6. Insulated inner tube; 61. Dividing groove; 7. Inductive component; 701. Insulated wire; 702. Inductive contact; 703. Measuring device; 704. Internal cavity; 705. Motor; 706. Magnetic convex shaft; 707. Through groove; 708. Spring locking plate; 709. Notch; 710. Connecting groove; 711. Spring partition; 712. Heat-conducting block; 8. Hollow cavity column; 9. Traction sleeve; 10. Heat-conducting wire; 11. 11. Open sleeve column; 12. Sliding plate; 13. Test assembly; 1301. Rheostat; 1302. First resistor block; 1303. Second resistor block; 1304. First magnetic block; 1305. Spring column; 1306. Power supply; 1307. Ammeter; 14. Expansion assembly; 1401. Telescopic bladder; 1402. Tension spring; 1403. Frame tube; 1404. Second magnetic block; 1405. Compression spring; 1406. Insulating pad; 15. Fixed pulley; 16. Limiting ring; 17. Return spring; 18. End cover alarm. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] This application provides a monitoring device for current transformers, which solves the problem that it is difficult to conveniently and effectively identify the cause of abnormal oil pressure in current transformer monitoring, thus avoiding unnecessary frequent inspections and maintenance. In use, by utilizing the current change formed by the test component 13 and the expansion component 14, it can be determined whether the oil pressure change in the current transformer is caused by oil leakage or abnormal oil temperature. At the same time, the inductive component 7 can not only protect the test component 13, but also monitor the partial discharge phenomenon inside the current transformer.

[0030] The technical solutions in this application are intended to solve the above-mentioned technical problems, and the overall approach is as follows.

[0031] Example 1

[0032] Please see Figures 1-13 A monitoring device for a current transformer includes an oil tank 1 and a porcelain bushing 2 connected to its bottom. It also includes: an oil inlet 3 installed at the lower middle of the front end of the porcelain bushing 2; a detection tube 4 installed in front of the oil inlet 3 and connected to both the oil inlet 3 and the porcelain bushing 2; a pressure slide 5 sliding inside the rear side of the detection tube 4, with a heat-insulating inner tube 6 installed in the middle of the pressure slide 5; a sensing component 7 installed inside the pressure slide 5 for sensing partial discharge currents released within the oil tank 1 and the porcelain bushing 2; a hollow cavity column 8 fixedly installed inside the front side of the detection tube 4; and a traction sleeve 9, one end of which is connected to the heat-insulating inner tube 6. The front end of tube 6 is connected, and the other end passes through the middle of the rear end of hollow cavity column 8 and extends into the interior of hollow cavity column 8; heat-conducting wire 10 is installed in the middle of heat-insulating inner tube 6 and traction sleeve 9; an open sleeve column 11 is installed in the middle of the front wall of hollow cavity column 8, and a sliding plate 12 slides inside the open sleeve column 11. The rear part of the sliding plate 12 is connected to the other end of the traction sleeve 9 extending into the interior of hollow cavity column 8; a test component 13 is provided at the top of the open sleeve column 11, and the test component 13 is connected to the sliding plate 12 and is triggered by the sliding of the sliding plate 12; an expansion component 14 is provided at the rear of the open sleeve column 11 and is triggered by the heat transfer of heat-conducting wire 10.

[0033] By setting up a detection tube 4, and ensuring that the detection tube 4 is connected to the oil tank 1 and the porcelain bushing 2, it is convenient for the detection tube 4 to directly contact and detect the triphosphite oil filled in the oil tank 1 and the porcelain bushing 2. Triphosphite oil is a synthetic ester liquid insulating material.

[0034] The specific detection process of the detection tube 4 is as follows: First, if an abnormal oil pressure occurs inside the oil tank 1 and the porcelain sleeve 2, the oil pressure inside the oil tank 1 and the porcelain sleeve 2 will decrease accordingly. This oil pressure change will directly affect the detection tube 4 connected to it, causing the pressure slide 5 inside it to slide inward under the pull of the internal oil pressure. The movement of the pressure slide 5 will drive the heat insulation inner tube 6, the traction sleeve 9 and the sliding plate 12 inside the open sleeve 11 connected to it to move together. As the sliding plate 12 slides backward, the first resistance block 1302 connected to it will also slide backward synchronously on the rheostat 1301. The result on the rheostat 1301 is that the first resistance block 1302 gradually moves away from the second resistance block 1303. When only the oil pressure changes, the second resistor block 1303 remains in place. This change will cause the distance between the first resistor block 1302 and the second resistor block 1303 to increase, and the resistance value they contain will also increase. Therefore, the current passing through the first resistor block 1302, the rheostat 1301 and the second resistor block 1303 in sequence will be affected by more resistance, making the outflowing detection current smaller. This indicates that the oil tank 1 and the porcelain sleeve 2 are affected by oil pressure, and the ammeter 1307 transmits the alarm to the end cover alarm 18. If the current continues to drop after exceeding the rated minimum current, it means that there is a large oil pressure, indicating that there may be an oil leakage problem.Secondly, abnormal oil pressure may also be affected by abnormal temperature. On the one hand, when abnormal temperature occurs in the oil tank 1 and the porcelain sleeve 2, the heat-conducting wire 10 in the traction sleeve 9 on the pressure slide 5 will transfer the rated heat to the telescopic bladder 1401 (this rated heat indicates an abnormally high temperature condition; in the normal temperature range, the heat-conducting wire 10 will not transfer heat, indicating that the heat-conducting wire 10 has a high thermal conductivity). Due to the thermal expansion and contraction characteristics, the inert gas in the telescopic bladder 1401 expands when heated. The expanding gas compresses the second magnetic block 1404 in the other end of the frame tube 1403, causing the outward-moving second magnetic block 1404 to repel the first magnetic block 1304 on the second resistor block 1303. This, in turn, pushes the second resistor block 1303 connected to the first magnetic block 1304 to slide backward on the rheostat 1301. The result on the rheostat 1301 is that the second resistor block 1303 continuously approaches the first resistor block 1302, the distance between them decreases, and the resistance contained in the rheostat decreases. The value also decreases accordingly. Therefore, the current passing through the first resistor block 1302, the rheostat 1301, and the second resistor block 1303 in sequence will be affected by the smaller resistance, resulting in a larger outflowing detection current. This current is transmitted by the ammeter 1307 to the end cover alarm 18, indicating that the oil tank 1 and the porcelain sleeve 2 are not leaking oil, but rather experiencing abnormal oil pressure due to abnormal internal temperature. On the other hand, it should be noted that the pressure slide 5 inside the detection tube 4 will also move inward due to the oil pressure generated by the abnormal oil temperature. Continuing the above process, it is clear that the movement of the pressure slide 5 is ultimately to move the first resistor block 1302 backward. Therefore, under this abnormal oil temperature condition, the first resistor block 1302 will also move backward a certain distance on the rheostat 1301. However, the oil pressure intensity caused by this oil temperature increases significantly slower than the oil pressure intensity caused by leakage. Therefore, although the first resistor block 1302 will move, the overall effect is that the distance between the second resistor block 1303 and the first resistor block 1302 gradually decreases.

[0035] In summary, by using changes in current to determine the oil pressure of oil conservator 1 and porcelain bushing 2, if the current decreases and continues to drop even after exceeding the rated minimum current, it indicates a large oil pressure and a possible oil leak. Conversely, if the current increases, it indicates that the oil pressure in oil conservator 1 and porcelain bushing 2 is not due to an oil leak, but rather an abnormal oil pressure caused by an abnormal internal temperature.

[0036] Further, please refer to Figure 6 Fixed pulleys 15 are installed on both the left and right sides of the middle of the rear wall of the hollow column 8. A traction sleeve 9 is set between the two fixed pulleys 15. The fixed pulleys 15 guide the traction sleeve 9 and prevent it from deviating and shaking, ensuring that the traction sleeve 9 moves in a straight line and is pulled by the pressure slide column 5.

[0037] Further, please refer to Figures 3-5A limiting ring 16 is provided on the outer front part of the pressure slide 5, and the limiting ring 16 is fixedly installed on the inner wall of the detection tube 4. The outer front part of the pressure slide 5 abuts against the rear part of the limiting ring 16. By setting the limiting ring 16, a clear stopping point and abutment position are provided for the front part of the pressure slide 5.

[0038] Further, please refer to Figures 3-5 A return spring 17 is provided between the pressure slide 5 and the hollow cavity column 8. One end of the return spring 17 is connected to the front outer side of the pressure slide 5, and the other end of the return spring 17 is connected to the rear outer side of the hollow cavity column 8. By providing the return spring 17, the pressure slide 5, which is pulled and moved by the abnormal oil pressure in the oil tank 1 and the porcelain sleeve 2, can be reset by the return spring 17 and limited to return to its original position by the limit ring 16 after the oil pressure disappears.

[0039] Example 2

[0040] Please see Figures 11-13 The inductive component 7 includes: an insulating wire 701 installed on the inner wall of the oil tank 1 and the porcelain bushing 2; multiple inductive contacts 702 installed at equal intervals on the insulating wire 701; and a measuring device 703 installed inside the pressure slide 5 and connected to one end of the insulating wire 701.

[0041] By setting up an insulating wire 701, inductive contacts 702, and a measuring device 703, the multiple inductive contacts 702 installed on the insulating wire 701 divide the interior of the oil conservator 1 and the porcelain bushing 2 into multiple layers from top to bottom. When a partial discharge occurs in one layer, the inductive contacts 702 come into contact and are transmitted through the insulating wire 701 to the measuring device 703, thereby triggering an induction signal. This facilitates the provision of a starting signal for the subsequent motor 705, while also sending a leakage signal to the external monitoring center.

[0042] It is important to note that partial discharge can occur inside the current transformer, releasing gas that dissolves in the transformer oil to form hydrogen. If the hydrogen level exceeds the limit, the current transformer may malfunction or operate abnormally, posing a significant safety hazard. Therefore, when the insulated wire 701 is installed on the inner wall of the oil conservator 1 and the porcelain bushing 2, an equal number of palladium alloy thin-film hydrogen sensors (not shown in the figure) can be installed on the inner wall of the oil conservator 1 and the porcelain bushing 2. These sensors serve as online monitoring devices for the hydrogen content in the current transformer oil, thereby detecting the hydrogen content generated in the volume between two adjacent palladium alloy thin-film hydrogen sensors. This allows for comprehensive internal detection of the oil conservator 1 and the porcelain bushing 2 from top to bottom.

[0043] A palladium alloy thin-film hydrogen sensor based on photoacoustic gas sensing technology operates on the principle of the photoacoustic effect of gases. This effect can be divided into two stages: light absorption, where the gas being measured absorbs modulated light of a specific wavelength and enters an excited state; and sound generation, where gas molecules, after absorbing light energy, convert the light energy into average molecular kinetic energy through a non-radiative relaxation process, heating the gas molecules. The gas temperature is modulated at the same frequency as the modulated light, causing periodic changes in gas pressure, which in turn excites corresponding sound waves in the photoacoustic cell. For hydrogen gas, which does not absorb in the infrared band, indirect photoacoustic spectroscopy can be used for measurement. For example, based on the principle that changes in hydrogen concentration cause changes in sound velocity, resulting in changes in the resonant frequency of the photoacoustic cell, ethylene, which has an absorption peak in the infrared band, is used as a reference gas. The hydrogen concentration is detected by measuring the shift in the resonant frequency of a first-order cylindrical resonant photoacoustic cell.

[0044] Palladium alloy nanofilm hydrogen sensors currently mainly employ thin-film resistive sensors, utilizing the catalytic decomposition of gases by metal thin films (such as...). Figure 14 As shown in the figure, hydrogen molecules are adsorbed onto the surface of the alloy film. Under the catalytic action of the palladium alloy film, the hydrogen molecules decompose into two hydrogen atoms. The hydrogen atoms diffuse into the interior of the palladium alloy lattice, causing lattice expansion and phase transition, resulting in a change in the conductivity of the alloy film. Based on this principle, the hydrogen content of 0 to 5000 ppm can be measured.

[0045] Further, please refer to Figures 11-13 The sensing component 7 also includes: an internal cavity 704, located inside the lower side of the pressure slide 5; a motor 705, installed in the middle of the rear wall of the internal cavity 704, with the output end of the motor 705 fixedly connected to one end of the magnetic convex shaft 706, the other end of the magnetic convex shaft 706 rotatably connected to the front wall of the internal cavity 704, and the motor 705 electrically connected to the sensing device 703; a through groove 707, located in the bottom wall of the internal cavity 704, with a spring locking plate 708 sliding within the through groove 707; and a notch 709, located in the detection... The lower part of the inner wall of the rear side of the measuring tube 4 has a recessed notch 709 with the same size as the lower part of the spring locking plate 708; the connecting groove 710 is opened on the top wall of the internal cavity 704, and a spring partition 711 slides in the connecting groove 710, and a heat-conducting block 712 is installed in the upper middle part of the spring partition 711; the inward end of the spring locking plate 708 and the spring partition 711 are both magnetic ends; the spring partition 711 slides in the partition groove 61 in the lower middle part of the heat-insulating inner tube 6, and the partition groove 61 is vertically aligned with the connecting groove 710.

[0046] When the current measuring device 703 detects a partial current, it transmits a detection signal to the motor 705. The motor 705 starts rotating, causing the magnetic convex shaft 706 to rotate. This causes the convex part of the magnetic convex shaft 706 to rotate from directly below to directly above and stop. After the convex part of the magnetic convex shaft 706 moves away from directly below, the spring locking plate 708 in the through groove 707, no longer attracted by the magnetic attraction of the magnetic convex shaft 706, begins to fall. This causes the lower part of the spring locking plate 708 to fall into the recess 709, thereby locking the pressure slide 5 and preventing it from moving. Meanwhile, the spring partition 711 in the connecting groove 710 faces the magnetic attraction of the rotating magnetic convex shaft 706. The spring partition 711 not only moves downward within the connecting groove 710, but also disengages from the partition groove 61, cutting off the heat transfer of the heat-conducting wire 10. This allows the inductive component 7 to lock the pressure slide 5 to prevent it from sliding after detecting partial discharge, and also to isolate the heat-conducting wire 10 to prevent heat transfer. Thus, when a partial current occurs in the oil tank 1 and the porcelain sleeve 2, it not only directly detects and alarms, but also locks the detection tube 4 to prevent the oil pressure generated by the partial discharge from affecting it. The convex part of the magnetic convex shaft 706 is a positive magnet, and the inward end of the spring locking plate 708 and the spring partition 711 is a negative magnet.

[0047] Example 3

[0048] Please see Figures 6-9 The test assembly 13 includes: a variable resistor 1301, installed on the upper part of the front wall of the hollow cavity column 8, and the variable resistor 1301 is vertically aligned with the open sleeve column 11; a first resistor block 1302, slidably installed on the rear part of the variable resistor 1301, and the bottom end of the first resistor block 1302 is connected to the top of the slide plate 12; a second resistor block 1303, slidably installed on the front part of the variable resistor 1301, and a first magnetic block 1304 is installed on the top of the second resistor block 1303; spring pillars 1305, respectively slidably installed on the left and right sides of the second resistor block 1303, and both spring pillars 1305 are fixedly installed on the upper part of the front wall of the hollow cavity column 8; a power supply 1306, installed on one side of the front part of the hollow cavity column 8, and the power supply 1306 is connected to the second resistor block 1303 through a stretchable lead; and an ammeter 1307, installed on the other side of the front part of the hollow cavity column 8, and the ammeter 1307 is connected to the first resistor block 1302 through a stretchable lead.

[0049] By setting up a rheostat 1301, a first resistor block 1302, a second resistor block 1303, a first magnetic block 1304, a spring column 1305, a power supply 1306, and an ammeter 1307, the change in current generated by the change in the distance between the first resistor block 1302 and the second resistor block 1303 sliding on the slide plate 12 can be used to determine whether the oil pressure problem of the oil conservator 1 and the porcelain bushing 2 is caused by oil leakage or abnormal temperature, thus enabling better identification and detection. Combined with partial discharge detection, more comprehensive monitoring of abnormal oil pressure problems in the oil conservator 1 and the porcelain bushing 2 can be achieved. Among them, the power supply 1306 is intermittently discharged, which facilitates the detection of continuous current flow.

[0050] Further, please refer to Figures 1-2 An end cover alarm 18 is installed at the front of the detection tube 4. The end cover alarm 18 is electrically connected to the ammeter 1307. The end cover alarm 18 emits different alarm sounds by transmitting the current magnitude signal from the ammeter 1307 to the end cover alarm 18, making it easy to directly distinguish whether it is an oil leakage abnormality, temperature abnormality or partial discharge abnormality.

[0051] Example 4

[0052] Please see Figures 7-10 The expansion assembly 14 includes: a telescopic bladder 1401, one end of which is connected to the front of the slide plate 12 and the other end of which is connected to the middle of the front wall of the hollow cavity column 8. The telescopic bladder 1401 is filled with inert gas and is made of a high-temperature resistant material; a tension spring 1402, which is disposed outside the telescopic bladder 1401 and whose two ends are respectively connected to the front of the slide plate 12 and the front wall of the hollow cavity column 8; a frame tube 1403, which is installed on the upper front end of the hollow cavity column 8. The lower port of the frame tube 1403 is connected to the telescopic bladder 1401, and the upper port of the frame tube 1403 penetrates the front of the hollow cavity column 8 and extends into the interior of the hollow cavity column 8; and a second magnet 1404, which is slidably installed inside the upper port of the frame tube 1403, and the front of the second magnet 1404 is connected to the inner wall of the upper port of the frame tube 1403 through a compression spring 1405.

[0053] By setting up a telescopic bladder 1401, a tension spring 1402, a frame tube 1403, a second magnetic block 1404, and a compression spring 1405, the inert gas filled in the telescopic bladder 1401 expands when heated by the heat-conducting wire 10. The expanded gas then pushes the second magnetic block 1404 in the upper port of the frame tube 1403 to move outward. The magnetic repulsion pushes the second resistive block 1303, which is externally connected to the first magnetic block 1304, to move. The first magnetic block 1304 and the second magnetic block 1404 are magnets with the same poles.

[0054] Further, please refer to Figure 9An insulating pad 1406 is installed at the upper port of the frame tube 1403, and the insulating pad 1406 abuts against the front of the first magnetic block 1304. By setting the insulating pad 1406, it can be ensured that the upper port of the frame tube 1403 and the first magnetic block 1304 connected to the second resistor block 1303 are electrically isolated, so that even if they are physically in contact with each other, it will not cause accidental current transmission.

[0055] 1. The detection tube can sensitively respond to abnormal oil pressure in the oil tank and porcelain sleeve by the displacement change of the internal pressure slide. When the oil pressure decreases, the movement of the pressure slide, traction sleeve and sliding plate increases the resistance value between the first and second resistance blocks on the rheostat, so that the current flowing through it decreases. This current is captured by the ammeter and transmitted to the end cover alarm, realizing an immediate alarm and effectively reminding maintenance personnel to pay attention to possible oil leakage problems.

[0056] 2. When the temperature inside the oil conservator and the porcelain bushing is abnormal, the heat-conducting wire transfers heat to the expansion bladder. Through the thermal expansion and contraction characteristics of the internal inert gas, the second resistance block is pushed to move on the rheostat, and the distance between it and the first resistance block decreases, which increases the current flowing through it. This current is captured by the ammeter and transmitted to the end cover alarm, effectively identifying abnormal oil pressure caused by abnormal temperature rather than oil leakage.

[0057] 3. By setting up insulated wires, inductive contacts, and measuring devices, the insulated wires are arranged on the inner walls of the oil conservator and the porcelain bushing, and the inductive contacts are arranged at equal intervals from top to bottom on the insulated wires, thereby dividing the interior of the oil conservator and the porcelain bushing into layers of detection zones, effectively detecting the partial discharge conditions of each layer inside the oil conservator and the porcelain bushing.

[0058] 4. When the measuring device detects partial discharge, it sends a start signal to the motor. The motor drives the magnetic cam shaft to rotate, causing the protruding part of the magnetic cam shaft to rotate upward. Since the spring locking plate below no longer has the magnetic attraction of the protruding part of the magnetic cam shaft, it falls into the recessed notch on the detection tube, thereby locking the pressure slide column. This helps to prevent the oil pressure changes caused by partial discharge from affecting the traction of the pressure slide column.

[0059] 5. The motor rotates to the upper magnetic cam shaft, and its protrusion aligns with the spring partition and magnetically attracts it, causing the spring partition to move down and cut off the heat transfer of the heat-conducting wire. This effectively isolates the abnormal temperature generated during partial discharge and the heat transfer phenomenon caused by it.

[0060] Example 5:

[0061] A monitoring device for a current transformer, comprising:

[0062] Multiple resistor blocks are mounted on a variable resistor. The first resistor block is displaced relative to the variable resistor under pressure changes, and the second resistor block is displaced relative to the variable resistor under temperature changes. The resistance change caused by the displacement of the first resistor block is in a different direction than the resistance change caused by the displacement of the second resistor block.

[0063] The first resistor block is mechanically connected to the hydraulic sliding device, which is in liquid communication with the sealed liquid storage device. The hydraulic sliding device slides when the pressure of the sealed liquid storage device changes, and the first resistor block is displaced under the drive of the mechanical connection device.

[0064] The second resistor block is thermally connected to the temperature moving device. One end of the temperature moving device is in thermal contact with the liquid in the sealed liquid storage device, and the other end is equipped with a temperature-sensitive component. The temperature-sensitive component drives the second resistor to move when the temperature changes.

[0065] In this embodiment, the hydraulic sliding device is essentially a sealed pressure balancing device, maintaining balance with the liquid inside the sealed container through an elastic component. A typical design uses a seal that slides within a pipe, moving when the pressure changes.

[0066] The temperature displacement device includes: a heat-conducting component, a medium storage component, and a telescopic component; one end of the heat-conducting component is in thermal contact with the liquid in the sealed liquid storage device, and the other end of the heat-conducting component is in thermal contact with the medium in the medium storage component. The heat-conducting component transfers the heat in the sealed liquid storage device to the medium in the medium storage component, causing the medium in the medium storage component to expand due to heat; the telescopic component is installed inside a long conduit extending outward from the medium storage component, and the expanded medium squeezes the telescopic component through the long conduit to extend outward along the inner wall of the conduit; the moving telescopic component pushes the second resistive block to move.

[0067] The telescopic component includes: a sealing block, a compression spring, and a second magnetic block; the sealing block is connected to the second magnetic block through the compression spring; the sealing block and the long conduit of the medium storage component form a sealing structure, and the expanded medium pushes the sealing block to slide inside the long conduit, thereby moving the second magnetic block; the first magnetic block set on the second resistive block moves with the second magnetic block, thereby moving the second resistive block.

[0068] The hydraulic sliding device includes a return spring, a pressure slide, a traction sleeve, and a detection tube;

[0069] The detection tube is connected to the sealed liquid storage device. One end of the return spring is fixed and the other end is connected to the pressure slide column. The pressure slide column is slidably installed inside the detection tube. The external force is balanced by the return spring and the liquid in the sealed liquid storage device. One end of the traction sleeve is fixed on the pressure slide column and the other end is mechanically connected to the first resistor block.

[0070] The hollow cavity column is fixed at the port of the detection tube. The hollow cavity column is a cylindrical cavity structure. An open sleeve column is fixed inside the front wall of the hollow cavity column. The rheostat is fixed above the open sleeve column. The traction sleeve passes through the rear wall of the hollow cavity column and is connected to the first resistor block. One end of the first resistor block is movably installed on the rheostat, and the other end is connected to the traction sleeve inside the open sleeve column.

[0071] The traction sleeve has a hollow structure, and heat-conducting wires are installed inside the cavity of the traction sleeve to transfer heat.

[0072] The pressure slide column in the hydraulic sliding device is equipped with a discharge locking device, which includes an electrical sensor, a servo mechanism, and a positioner. The discharge locking device detects the current in the sealed liquid storage device through the electrical sensor. When the current is detected, the servo mechanism drives the positioner to move, passing the positioner through the pressure slide column and positioning it on the detection tube, thus fixing the pressure slide column and the detection tube.

[0073] The discharge locking device also includes: a heat conductor; the heat conductor is a spring plate with heat-conducting contacts; the heat-conducting component passes through the pressure slide, the heat conductor is radially inserted into the heat-conducting component, and the heat-conducting contacts on both sides contact the heat-conducting component to achieve heat transfer.

[0074] The servo structure is a motor, with a magnetic cam shaft fixed at the output end of the motor; the positioner is a spring locking plate, and the heat conductor is a spring partition plate with heat-conducting contacts on the spring partition plate.

[0075] The spring locking plate is mounted on the sliding component. When the strong magnetic end of the magnetic cam shaft approaches the spring locking plate, it attracts the spring locking plate to retract inside the sliding component, and the sliding component is in a sliding state. The heat-conducting contact on the spring partition is inserted into the heat-conducting component, maintaining the heat-conducting function of the heat-conducting component. When the strong magnetic end of the magnetic cam shaft moves away from the spring locking plate, the spring locking plate partially pops out of the sliding component and inserts into the corresponding groove, and the sliding component is in a locked state. The heat-conducting contact on the spring partition disengages from the heat-conducting component, blocking the heat-conducting function of the heat-conducting component.

[0076] Electrical sensors include insulated wires, inductive contacts, and measuring devices;

[0077] The insulated wire is installed inside the sealed liquid storage device, the inductive contact is installed on the insulated wire, and the measuring device is installed inside the sliding component and connected to one end of the insulated wire.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A monitoring device for a current transformer, comprising: Two sliding resistance blocks are mounted on a sliding rheostat. The first resistance block is displaced relative to the rheostat under pressure changes, and the second resistance block is displaced relative to the rheostat under temperature changes. The resistance change caused by the displacement of the first resistance block is in a different direction than the resistance change caused by the displacement of the second resistance block. The first resistor block is mechanically connected to the hydraulic sliding device, which is in liquid communication with the sealed liquid storage device. The hydraulic sliding device slides when the pressure of the sealed liquid storage device changes, and under the drive of the mechanical connection device, the first resistor block is displaced and moves away from the second resistor block, which reduces the outflowing detection current, indicating that the sealed liquid storage device is affected by the oil pressure. The second resistor block is thermally connected to the temperature moving device. One end of the temperature moving device is in thermal contact with the liquid in the sealed liquid storage device, and the other end is equipped with a temperature-sensitive component. When the temperature changes, the temperature-sensitive component drives the second resistor block to move closer to the first resistor block, which increases the outflowing detection current, indicating that the sealed liquid storage device is affected by the temperature.

2. The monitoring device for a circuit transformer as described in claim 1, characterized in that, The temperature displacement device includes: a heat-conducting component, a medium storage component, and a telescopic component; one end of the heat-conducting component is in thermal contact with the liquid in the sealed liquid storage device, and the other end of the heat-conducting component is in thermal contact with the medium in the medium storage component. The heat-conducting component transfers the heat in the sealed liquid storage device to the medium in the medium storage component, causing the medium in the medium storage component to expand due to heat; the telescopic component is installed inside a long conduit extending outward from the medium storage component, and the expanded medium squeezes the telescopic component through the long conduit to extend outward along the inner wall of the conduit; the moving telescopic component pushes the second resistive block to move.

3. The monitoring device for a circuit transformer as described in claim 2, characterized in that, The telescopic component includes: a sealing block, a compression spring, and a second magnetic block; the sealing block is connected to the second magnetic block through the compression spring; the sealing block and the long conduit of the medium storage component form a sealing structure, and the expanded medium pushes the sealing block to slide inside the long conduit, thereby moving the second magnetic block; the first magnetic block set on the second resistive block moves with the second magnetic block, thereby moving the second resistive block.

4. The monitoring device for a current transformer as described in claim 1, characterized in that, The hydraulic sliding device includes a return spring, a pressure slide, a traction sleeve, and a detection tube; The detection tube is connected to the sealed liquid storage device; one end of the reset spring is fixed and the other end is connected to the pressure slide column, which is slidably installed inside the detection tube. The external force is balanced with the liquid in the sealed liquid storage device through the reset spring; one end of the traction sleeve is fixed on the pressure slide column and the other end is mechanically connected to the first resistor block.

5. A monitoring device for a circuit transformer as described in claim 4, characterized in that, It also includes a hollow cavity column; the hollow cavity column is fixed at the port of the detection tube, and the hollow cavity column is a cylindrical cavity structure. An open sleeve column is fixed inside the front wall of the hollow cavity column, and a sliding rheostat is fixed above the open sleeve column; the traction sleeve passes through the rear wall of the hollow cavity column and is connected to the first resistor block. One end of the first resistor block is movably mounted on the sliding rheostat, and the other end is connected to the traction sleeve inside the open sleeve column.

6. The monitoring device for a circuit transformer as described in claim 5, characterized in that, The traction sleeve has a hollow structure, and heat-conducting wires are installed inside the cavity of the traction sleeve to transfer heat.

7. A monitoring device for a current transformer as described in claim 4, characterized in that, The pressure slide column in the hydraulic sliding device is equipped with a discharge locking device, which includes an electrical sensor, a servo mechanism, and a positioner. The discharge locking device detects the current in the sealed liquid storage device through the electrical sensor. When the current is detected, the servo mechanism drives the positioner to move, passing the positioner through the pressure slide column and positioning it on the detection tube, thus fixing the pressure slide column and the detection tube.

8. A monitoring device for a current transformer as described in claim 7, characterized in that, The discharge locking device also includes: a heat conductor; the heat conductor is a spring plate with heat-conducting contacts; the heat-conducting component passes through the pressure slide, the heat conductor is radially inserted into the heat-conducting component, and the heat-conducting contacts on both sides contact the heat-conducting component to achieve heat transfer.

9. A monitoring device for a current transformer as described in claim 8, characterized in that, Electrical sensors include insulated wires, inductive contacts, and measuring devices; The insulated wire is installed inside the sealed liquid storage device, the inductive contact is installed on the insulated wire, and the measuring device is installed inside the sliding component and connected to one end of the insulated wire.

10. A sealed liquid storage device, comprising: A monitoring device for a current transformer as described in any one of claims 1-9.

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