Cable joint on-line monitoring device based on CT electricity taking and optical fiber sensing

Abstract

The invention discloses a cable joint on-line monitoring device based on CT electricity taking and optical fiber sensing, and relates to the field of cable monitoring, the cable joint on-line monitoring device comprises a CT electricity taking device and an optical fiber sensor, the optical fiber sensor is installed below the CT electricity taking device, an upper positioning seat is fixedly arranged on the upper side of the CT electricity taking device, and a lower positioning seat is installed at the bottom of the optical fiber sensor; an optical fiber probe is installed at the end of the CT electricity taking device, an optical fiber probe is installed at the end of the optical fiber sensor, meanwhile, an induction coil is installed at the end of the CT electricity taking device, and the optical fiber sensor supplies energy through the CT electricity taking device. According to the cable joint online monitoring device based on CT power taking and optical fiber sensing, continuous energy supply is achieved through the current of the cable, long-term stable operation of the optical fiber sensor is ensured, the later maintenance cost and workload are reduced, external mains supply and solar energy are not needed, and installation is convenient and fast; the larger the current is, the more sufficient the induction electric energy is, regular manual replacement or charging is not needed, and the maintenance cost and risk are reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cable monitoring, in particular to a kind of cable joint on-line monitoring device based on CT power taking and optical fiber sensing. BACKGROUND

[0002] With the continuous advancement of urbanization, in order to further strengthen the beautification of city, many cities gradually carry out the underground transformation of 10KV overhead line, resulting in a large number of urban underground power cables; in many power supply lines, affected by the actual situation of installation environment and power supply line distance, most of the cables are installed with cable intermediate joints, which are the weak points in power supply lines, and the cable intermediate joints are basically installed in cable trench or directly buried, which cannot be directly monitored and maintained or cannot be maintained; due to the change of load and environmental factors during operation or the installation process and sealing of cable joints not meeting the standard specification, the intermediate joint of urban underground cable is damp or water enters, resulting in reduced insulation performance and cable breakdown short circuit fault, which will cause large area power failure; the intermediate joints of the cable in a city are basically tens of thousands, lack effective positioning management, and it is difficult to find the joint position after failure; in view of this situation, the running state device of each intermediate joint of the city underground cable joint on-line monitoring device uploads the running state of each joint to the on-line monitoring system on the cloud server in the form of data through the Internet of Things technology; the existing cable joint monitoring device mostly uses monitoring tools to carry out real-time monitoring work in underground tunnel, which is low in efficiency; In order to solve the above problems, through retrieval, the Chinese patent with publication number CN218301014U discloses a kind of city underground cable joint on-line monitoring device, which includes box body, mounting plate, external monitoring mechanism, monitoring mechanism for detecting cable joint arranged in the box body and cover for sealing the box body arranged above the box body, the monitoring mechanism includes analog quantity acquisition circuit, communication module, antenna, MCU, fire extinguishing control module, inner water immersion sensor, outer water immersion sensor and temperature sensor, which is detected by inner water immersion sensor and temperature sensor; The above device can facilitate the operation of the staff to view information, thereby realizing the purpose of on-line monitoring of city underground cable joint and effectively improving the safety of line, but in actual use, when monitoring the cable joint, the monitoring equipment needs additional power supply, cannot extract power from the cable for use, the additional power supply (especially battery power supply) has life limit, needs regular manual replacement or charging, and the distribution of cable joint is often "dispersed, remote and difficult to reach", which significantly increases maintenance cost and risk. SUMMARY

[0003] The application aims to provide a cable joint online monitoring device based on CT power taking and optical fiber sensing to solve the defects mentioned in the background.

[0004] To achieve the above-mentioned purpose, the application provides a cable joint online monitoring device based on CT power taking and optical fiber sensing, which comprises a CT power taker and an optical fiber sensor, the optical fiber sensor is installed below the CT power taker, an upper positioning seat is fixedly arranged on the upper side of the CT power taker, a lower positioning seat is installed at the bottom of the optical fiber sensor, an optical fiber probe is installed at the end of the CT power taker, an optical fiber probe is installed at the end of the optical fiber sensor, an induction coil is installed at the end of the CT power taker, and the optical fiber sensor is powered by the CT power taker.

[0005] Further, the upper positioning seat and the lower positioning seat are arranged in parallel, a folding mechanism is installed between the upper positioning seat and the lower positioning seat, and the upper positioning seat and the lower positioning seat are unfolded and folded through the folding mechanism.

[0006] Further, the folding mechanism comprises a rocker arm A, a rocker arm B, a center pin, a locking piece, a locking column and a guide seat, the rocker arm A and the rocker arm B are arranged in an "X" shape, connection holes are formed in the middle of the rocker arm A and the rocker arm B, the center pin is arranged in the two groups of connection holes, and the rocker arm A and the rocker arm B are movably connected through the center pin.

[0007] Further, lock holes are formed in the bottom of the rocker arm A and the rocker arm B, the locking columns are inserted into the two groups of lock holes, and the locking pieces are fixedly arranged at the ends of the two groups of locking columns.

[0008] Further, the connection pins are fixedly arranged at one end of the rocker arm A and the rocker arm B, and the guide seats are installed at the other end of the rocker arm A and the rocker arm B, the upper positioning seat and the lower positioning seat have the same structure, and the lower positioning seat comprises a side plate, a track hole, a butt joint groove, a connecting piece and a butt joint seat.

[0009] Further, the side plates are fixedly arranged at the two sides of the upper positioning seat and the lower positioning seat, the connection holes are formed in one side of the side plate, the track holes are formed in the other side of the side plate, the connection pin at one end of the rocker arm A is movably inserted into the connection hole on the upper positioning seat, and the guide seat at the other end of the rocker arm A is slidably connected in the track hole on the lower positioning seat; the connection pin at one end of the rocker arm B is movably inserted into the connection hole on the lower positioning seat, and the guide seat at the other end of the rocker arm B is slidably connected in the track hole on the upper positioning seat, and the track hole is rectangular.

[0010] Further, the two groups of butt joint grooves are formed on the surfaces of the upper positioning seat and the lower positioning seat, the sizes of the butt joint grooves and the butt joint seats are matched, the butt joint seats are slidably arranged in the butt joint grooves, the butt joint grooves and the butt joint seats are dovetail-shaped, and the two groups of butt joint seats are screwed on the optical fiber sensor and the CT power taker.

[0011] Further, the optical fiber sensor is positioned and installed on the upper positioning seat through the butt joint groove and the butt joint seat, and the CT power extractor is positioned and installed on the lower positioning seat through the butt joint groove and the butt joint seat, and the optical fiber sensor monitors the cable joint on line through the optical fiber probe at the end thereof.

[0012] Further, the optical fiber sensor and the CT power extractor are unfolded through the folding mechanism to form a maintenance state, and the optical fiber sensor and the CT power extractor are folded through the folding mechanism to form a working state, and the rocker arm A and the rocker arm B on the folding mechanism are limited and locked through the locking piece and the locking column when unfolded.

[0013] Compared with the prior art, the beneficial effects of the present application are: 1. The inductive coil on the CT power extractor is sleeved on the main cable, and the load current in the main cable induces a weak current in the CT coil, which is converted into stable direct current power after rectification, voltage stabilization and energy storage, to supply power to the optical fiber sensor, without the need for additional external power supply lines or regular battery replacement, thereby simplifying the installation process and reducing installation costs, while relying on the current of the cable itself to achieve continuous power supply, ensuring long-term stable operation of the optical fiber sensor, reducing maintenance costs and workload, without the need for external power supply, solar power, and convenient installation; the greater the current, the more sufficient the induced power, without the need for regular manual replacement or charging, thereby reducing maintenance costs and risks. 2. The upper positioning seat and the lower positioning seat switch between the working state and the maintenance state through the folding mechanism, and the optical fiber sensor and the CT power extractor maintain an adaptive working distance and relative position when folded, thereby ensuring the functional stability of the equipment during normal operation, and providing sufficient maintenance operation space for the two after unfolding, without the need for disassembly of the overall structure to conveniently carry out maintenance and detection work, thereby greatly improving the maintenance efficiency. 3. The folding mechanism is unfolded and limited and locked through the cooperation of the rocker arm A, the rocker arm B, the locking piece and the locking column, which can effectively prevent accidental folding of the mechanism during maintenance, thereby ensuring the safety of the maintenance personnel and avoiding collision damage to the optical fiber sensor and the CT power extractor caused by shaking of the mechanism, and the structural stability in the locked state also provides good conditions for precise maintenance. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a front view of the structure of the present application; Figure 2 is a side view of the structure of the present application; Figure 3 is a bottom view of the structure of the present application; Figure 4 is a front view of the structure of the present application; Figure 5 The schematic view of the upper positioning seat and the lower positioning seat installation structure of the present application structure; Figure 6 The top view of the present application structure Figure 6 ; Figure 7 The schematic view of the upper positioning seat and the lower positioning seat folding of the present application structure; Figure 8 The side view of the present application structure Figure 7 . The drawings

[0015] 1, fiber sensor; 11, fiber probe; 2, upper positioning seat; 3, CT power supply; 31, induction coil; 4, lower positioning seat; 41, side plate; 42, track hole; 43, butt joint groove; 44, connecting piece; 441, butt joint seat; 5, folding mechanism; 51, rocker arm A; 52, rocker arm B; 53, center pin; 54, locking piece; 541, locking column; 55, guide seat. DETAILED DESCRIPTION

[0016] Specific implementation method one: please refer to Figures 1-8 , the present application provides a technical scheme: a kind of cable joint on-line monitoring device based on CT power supply and fiber sensing, including CT power supply 3 and fiber sensor 1, CT power supply 3 below is equipped with fiber sensor 1, and CT power supply 3 upper side is fixedly provided with upper positioning seat 2, while fiber sensor 1 bottom is equipped with lower positioning seat 4, CT power supply 3 end is equipped with fiber probe 11, and fiber sensor 1 end is equipped with fiber probe 11, while CT power supply 3 end is equipped with induction coil 31, fiber sensor 1 is energized by CT power supply 3.

[0017] Working principle: in actual use, the cable joint is monitored by the device, the specific way is: the optical fiber probe 11 on the optical fiber sensor 1 is installed on the position to be monitored of the cable joint, the cable joint is monitored online by the optical fiber sensor 1, and the optical fiber sensor 1 is powered by the CT power extractor 3, the sensing coil 31 on the CT power extractor 3 is sleeved on the main cable, the load current in the main cable will induce a weak current in the CT coil, after rectification, voltage stabilization and energy storage treatment, it is converted into stable direct current power to supply power for the optical fiber sensor 1, without external power supply, solar energy, convenient installation; the greater the current, the more sufficient the induced power, suitable for 10kV and above high-voltage cable joints; no need for regular manual replacement or charging, reduce maintenance cost and risk; when the optical fiber probe 11 on the optical fiber sensor 1 monitors the cable joint online, the optical fiber probe 11 is first installed in a way of sticking or embedding on the key monitoring part of the cable joint, such as the joint body, the connection point of the insulating layer and the conductor, the sealing place, etc., to ensure that the probe can directly sense the physical parameter change of the joint during operation, then the light source module in the optical fiber probe 11, such as laser diode, will emit a specific wavelength of probe light signal, the light signal is transmitted to the cable joint monitoring point along the optical fiber core of the probe, when the cable joint has temperature rise, local discharge or slight vibration displacement due to load change, insulation aging, poor contact, etc., these physical changes will cause the corresponding changes of the refractive index, transmission loss or light scattering characteristics of the optical fiber, such as Rayleigh scattering, Raman scattering, so that the probe light produces light signal modulation related to the monitoring parameter in the transmission process, such as light intensity, phase, frequency change, then the light detection module of the optical fiber probe 11 will receive the reflected and scattered light signal modulated by the physical change of the cable joint in real time, and convert it into corresponding electric signal, after that, the electric signal will be transmitted to the signal processing unit of the optical fiber sensor 1 for filtering, amplification, demodulation and data operation, and the real-time temperature, local discharge intensity, vibration displacement and other key operating parameters of the cable joint are extracted, finally the monitoring data is uploaded to the background monitoring system in real time through the communication module of the sensor, the system analyzes the data and compares it with the preset threshold value, if the parameter is abnormal, the early warning is triggered immediately, so as to realize 24-hour uninterrupted online monitoring and fault early warning of the running state of the cable joint; it has the advantages of anti-electromagnetic interference, optical fiber is an insulator, not affected by high-voltage electric field, corrosion resistant, long transmission distance, high measurement accuracy, suitable for harsh operating environment of high-voltage cable joint.

[0018] Specific implementation method two: this implementation method is a further limitation of the specific implementation method one, the upper positioning seat 2 and the lower positioning seat 4 are arranged in parallel, and the folding mechanism 5 is installed between the upper positioning seat 2 and the lower positioning seat 4.

[0019] The folding mechanism 5 comprises a rocker arm A51, a rocker arm B52, a center pin shaft 53, a locking piece 54, a locking column 541 and a guide seat 55, and the rocker arm A51 and the rocker arm B52 are arranged in an "X" shape, and the middle part of each of the rocker arm A51 and the rocker arm B52 is provided with a connecting hole, and the center pin shaft 53 is arranged through the inside of the two groups of connecting holes, and the rocker arm A51 and the rocker arm B52 are movably connected through the center pin shaft 53.

[0020] The bottom of each of the rocker arm A51 and the rocker arm B52 is provided with a lock hole, and the locking column 541 is inserted into the inside of the two groups of lock holes, and the end of each of the two groups of locking columns 541 is fixedly provided with the locking piece 54.

[0021] One end of each of the rocker arm A51 and the rocker arm B52 is fixedly provided with a connecting pin shaft, and the other end of each of the rocker arm A51 and the rocker arm B52 is provided with the guide seat 55, and the upper positioning seat 2 and the lower positioning seat 4 have the same structure, and the lower positioning seat 4 comprises a side plate 41, a track hole 42, a butt joint groove 43, a connecting piece 44 and a butt joint seat 441.

[0022] The upper positioning seat 2 and the lower positioning seat 4 are fixedly provided with the side plate 41 on both sides, the side plate 41 is provided with a connecting hole on one side, and the side plate 41 is provided with the track hole 42 on the other side, the connecting pin shaft at one end of the rocker arm A51 is movably inserted into the connecting hole on the upper positioning seat 2, and the guide seat 55 at the other end of the rocker arm A51 is slidably connected to the inside of the track hole 42 on the lower positioning seat 4; the connecting pin shaft at one end of the rocker arm B52 is movably inserted into the connecting hole on the lower positioning seat 4, and the guide seat 55 at the other end of the rocker arm B52 is slidably connected to the inside of the track hole 42 on the upper positioning seat 2, and the track hole 42 is in a rectangular shape.

[0023] The upper positioning seat 2 and the lower positioning seat 4 are provided with two groups of butt joint grooves 43 on the surface, and the size of the butt joint groove 43 is matched with the butt joint seat 441, and the butt joint seat 441 is slidably arranged in the inside of the butt joint groove 43, and the butt joint groove 43 and the butt joint seat 441 are in a dovetail shape, and the two groups of butt joint seats 441 are respectively screwed on the optical fiber sensor 1 and the CT power extractor 3.

[0024] The optical fiber sensor 1 and the CT power extractor 3 are unfolded to form a maintenance state through the folding mechanism 5, and the optical fiber sensor 1 and the CT power extractor 3 are folded to form a working state through the folding mechanism 5, and the rocker arm A51 and the rocker arm B52 on the folding mechanism 5 are limited and locked through the locking piece 54 and the locking column 541 when the folding mechanism 5 is unfolded.

[0025] As Figures 1-8As shown: by making the optical fiber sensor 1 on the upper positioning seat 2, the CT power extractor 3 on the lower positioning seat 4 adopt butt joint groove 43 and butt joint seat 441 for positioning installation, it can ensure that the installation positions of the two are accurate and unified, and the standardized butt joint structure also simplifies the installation process, reduces the assembly difficulty and time cost; the upper positioning seat 2 and the lower positioning seat 4 realize the switching between the working state and the maintenance state by means of the folding mechanism 5, and when folding, the optical fiber sensor 1 and the CT power extractor 3 can maintain the adaptive working distance and relative position, guarantee the function stability of the equipment in normal operation, and after unfolding, it can provide sufficient maintenance operation space for the two, without disassembling the overall structure, it can conveniently carry out maintenance and detection work, and greatly improve the maintenance efficiency; after unfolding of the folding mechanism 5, the rocker arm A51, the rocker arm B52 and the locking piece 54, the locking column 541 are matched to realize limiting locking, which can effectively prevent accidental folding of the mechanism during maintenance, not only guarantee the operation safety of the maintenance personnel, but also avoid the collision damage of the optical fiber sensor 1 and the CT power extractor 3 caused by the shaking of the mechanism, and at the same time, the structural stability in the locked state also provides good conditions for accurate maintenance; During unfolding of the upper positioning seat 2 and the lower positioning seat 4, the included angle between the rocker arm A51 and the rocker arm B52 in the "X" shape distribution is reduced at this time, and the guide seat 55 at the end of the rocker arm A51 and the rocker arm B52 is respectively slidably arranged in the corresponding track hole 42, which can limit and guide the upper positioning seat 2 and the lower positioning seat 4 during unfolding.

[0026] Specific implementation method three: this implementation method is a further limitation of the specific implementation method one, the optical fiber sensor 1 on the upper positioning seat 2 is positioned and installed through the butt joint groove 43 and the butt joint seat 441, and the CT power extractor 3 on the lower positioning seat 4 is positioned and installed through the butt joint groove 43 and the butt joint seat 441, and the optical fiber sensor 1 is online monitored through the optical fiber probe 11 at the end of the optical fiber sensor 1.

[0027] As Figures 1-4As shown: the optical fiber probe 11 of the optical fiber sensor 1 is directly installed at the cable joint monitoring position, can capture the real-time state of the monitoring point at close range, avoid the information deviation of indirect monitoring, greatly improve the accuracy and authenticity of the monitoring data; the optical fiber sensor 1 itself has strong anti-electromagnetic interference characteristics, can work stably in the strong electromagnetic environment of the cable operation, effectively avoids the influence of electromagnetic interference on the monitoring signal, and guarantees the reliability of online monitoring; the optical fiber sensor 1 is powered by the CT power supply 3, without additional external power supply line and without regular battery replacement, simplifying the installation process and reducing the installation cost, at the same time, relying on the current of the cable itself to realize continuous power supply, ensuring the long-term stable operation of the optical fiber sensor 1, reducing the later maintenance cost and workload; the whole device realizes online monitoring of the cable joint, without interrupting the normal operation of the cable for offline detection, guaranteeing the continuous and stable work of the cable system, reducing the production or power supply loss caused by shutdown detection; the length of the wire harness installed at the end of the optical fiber probe 11 and the inductor 31 is longer than that in the figure, which is convenient for use.

Claims

1. An online monitoring device for cable joints based on CT power supply and fiber optic sensing, comprising a CT power supply device (3) and a fiber optic sensor (1), characterized in that: A fiber optic sensor (1) is installed below the CT power source (3), and an upper positioning seat (2) is fixedly installed on the upper side of the CT power source (3). At the same time, a lower positioning seat (4) is installed at the bottom of the fiber optic sensor (1). A fiber optic probe (11) is installed at the end of the CT power source (3), and a fiber optic probe (11) is installed at the end of the fiber optic sensor (1). At the same time, an induction coil (31) is installed at the end of the CT power source (3). The fiber optic sensor (1) is powered by the CT power source (3).

2. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 1, characterized in that: The upper positioning seat (2) and the lower positioning seat (4) are arranged in parallel, and a folding mechanism (5) is installed between the upper positioning seat (2) and the lower positioning seat (4). The upper positioning seat (2) and the lower positioning seat (4) are unfolded and folded through the folding mechanism (5).

3. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 2, characterized in that: The folding mechanism (5) includes rocker arm A (51), rocker arm B (52), center pin (53), locking piece (54), locking post (541) and guide seat (55). Rocker arm A (51) and rocker arm B (52) are arranged in an "X" shape. Both rocker arm A (51) and rocker arm B (52) have connecting holes in the middle. The center pin (53) is installed through the two sets of connecting holes. Rocker arm A (51) and rocker arm B (52) are movably connected through the center pin (53).

4. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 3, characterized in that: The bottom of both rocker arm A (51) and rocker arm B (52) is provided with a lock hole, and a locking pin (541) is inserted inside both sets of lock holes, and a locking piece (54) is fixedly provided at the end of both sets of locking pins (541).

5. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 4, characterized in that: One end of each rocker arm A (51) and rocker arm B (52) is fixedly provided with a connecting pin, and the other end of each rocker arm A (51) and rocker arm B (52) is provided with a guide seat (55). The upper positioning seat (2) and the lower positioning seat (4) have the same structure. The lower positioning seat (4) includes a side plate (41), a track hole (42), a docking groove (43), a connecting piece (44), and a docking seat (441).

6. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 5, characterized in that: Both sides of the upper positioning seat (2) and the lower positioning seat (4) are fixedly provided with side plates (41). A connecting hole is opened on one side of the side plate (41), and a track hole (42) is opened on the other side of the side plate (41). The connecting pin of one end of the rocker arm A (51) is movably inserted into the connecting hole on the upper positioning seat (2), and the guide seat (55) of the other end of the rocker arm A (51) is slidably connected to the track hole (42) on the lower positioning seat (4). The connecting pin of one end of the rocker arm B (52) is movably inserted into the connecting hole on the lower positioning seat (4), and the guide seat (55) of the other end of the rocker arm B (52) is slidably connected to the track hole (42) on the upper positioning seat (2). The track hole (42) is rectangular.

7. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 6, characterized in that: The surfaces of the upper positioning seat (2) and the lower positioning seat (4) are provided with two sets of docking grooves (43), and the dimensions of the docking grooves (43) and the docking seat (441) are matched. At the same time, the docking seat (441) is slidably disposed inside the docking grooves (43). The docking grooves (43) and the docking seat (441) are in the shape of dovetails. The two sets of docking seats (441) are screwed onto the fiber optic sensor (1) and the CT collector (3) respectively.

8. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 7, characterized in that: The fiber optic sensor (1) is positioned and installed on the upper positioning seat (2) through the docking groove (43) and the docking seat (441), and the CT receiver (3) is positioned and installed on the lower positioning seat (4) through the docking groove (43) and the docking seat (441). At the same time, the fiber optic sensor (1) monitors the cable joint online through the fiber optic probe (11) at its end.

9. The online monitoring device for cable joints based on CT power supply and fiber optic sensing according to claim 8, characterized in that: The fiber optic sensor (1) and the CT receiver (3) are unfolded through the folding mechanism (5) to form a maintenance state, and the fiber optic sensor (1) and the CT receiver (3) are folded through the folding mechanism (5) to form a working state. At the same time, after the folding mechanism (5) is unfolded, the rocker arm A (51) and rocker arm B (52) on it are limited and locked by the locking piece (54) and the locking post (541).

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