A partial discharge monitoring component and partial discharge monitoring device for high voltage cables

Abstract

The present invention relates to a partial discharge monitoring component and a partial discharge monitoring device for a high-voltage cable. The partial discharge monitoring component comprises: a first assembly, a second assembly and a current transformer; the first assembly and the second assembly are detachably connected; a first ring body is arranged on the first assembly, and a second ring body is arranged on the second assembly; the radial cross-section of the first ring body and the radial cross-section of the second ring body are both semicircular; the first ring body and the second ring body are arranged relative to each other and positioned by plugging to form a channel allowing the high-voltage cable to pass through; the current transformer is fixed to the inner wall of the first ring body. The present invention can reduce the complexity of the partial discharge monitoring component and reduce the construction period of the partial discharge monitoring system.

Description

Technical Field

[0001] The invention relates to the field of high-voltage cable monitoring, and in particular to a partial discharge monitoring component and a partial discharge monitoring device for a high-voltage cable. Background Art

[0002] High-voltage cables are an important part of the power system. With the development of high-voltage and ultra-high-voltage transmission lines, power cables have been widely used due to their unique technical advantages. During the operation of the cable, due to factors such as internal impurities, semiconductor layer protrusions, and accumulation of space charges under voltage, local electric field stress concentration will occur, resulting in partial discharge, which will affect safe operation; the partial discharge of the cable is closely related to the insulation condition of the cable, so judging the insulation state by monitoring partial discharge is an effective means to achieve insulation monitoring and diagnosis.

[0003] At present, partial discharge monitoring generally adopts the form of online monitoring. Online monitoring needs to be connected to the back-end platform to form a system. To build an online monitoring system, it is necessary to distribute and install multiple partial discharge monitoring components on the high-voltage cable. The partial discharge monitoring components generally implement the partial discharge monitoring process by clamping the cable and based on current transformers. However, the structure and process of existing partial discharge monitoring components when installed on the cable are too complicated, resulting in the time-consuming and labor-intensive distribution process of the partial discharge monitoring components, which prolongs the construction period of the partial discharge monitoring system, increases the construction cost of the entire system, and is not conducive to the construction of the partial discharge online monitoring system. Summary of the invention

[0004] The object of the present invention is to provide a partial discharge monitoring component and a partial discharge monitoring device for a high voltage cable, so as to reduce the complexity of the partial discharge monitoring component and shorten the construction period of the partial discharge monitoring system.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] A partial discharge monitoring assembly for a high voltage cable comprises: a first assembly, a second assembly and a current transformer;

[0007] The first assembly and the second assembly are detachably connected; a first ring body is provided on the first assembly, and a second ring body is provided on the second assembly; the radial cross-section of the first ring body and the radial cross-section of the second ring body are both semicircular; the first ring body and the second ring body are arranged opposite to each other and positioned by plugging, so as to form a passage allowing the high-voltage cable to pass through;

[0008] The current transformer is fixed to the inner wall of the first ring body.

[0009] Optionally, the first ring body includes a positioning post, and the second ring body includes a positioning groove matching the positioning post, and the positioning post is inserted into the positioning groove.

[0010] Optionally, the cross-sections of the positioning column and the positioning groove are both circular, and the cross-section radius of the positioning column is smaller than the cross-section radius of the positioning groove.

[0011] Optionally, the first assembly and the second assembly are connected by plugging and are radially fixed by a latch after plugging.

[0012] Optionally, the first assembly component includes an assembly block, and the second assembly component includes an assembly groove; the assembly block is axially inserted into the assembly groove; the assembly block is radially provided with a plug hole, and the pin radially passes through the plug hole of the assembly block and extends into the assembly groove.

[0013] Optionally, the second assembly is further provided with a slot body, and the slot body is located on the side of the assembly slot;

[0014] Two stoppers are fixed on both sides of the inner wall of the opening of the slot body, and a plug hole is provided at the bottom of the slot body; the top end of the plug is connected to the fixed baffle, and the bottom end of the plug passes through the plug hole at the bottom of the slot body and is inserted into the assembly block; a spring is sleeved on the plug, and the spring is located between the fixed baffle and the bottom of the slot body;

[0015] The fixed baffle is a rectangular structure, and the length of the rectangular surface of the fixed baffle connected to the pin is greater than the distance between the two blocks, and the width is less than the distance between the two blocks; when the fixed baffle is located in the slot body and between the block and the bottom of the slot body, the spring is in a compressed state, and the pin is inserted into the assembly block; when the fixed baffle is located outside the slot body, the pin is pulled out of the assembly block.

[0016] Optionally, it further comprises an adjusting stud and a clamping arc plate of an arc structure; the clamping arc plate is located in the channel formed by the first ring body and the second ring body, and the clamping arc plate is used to carry the high-voltage cable in the channel;

[0017] An adjustment groove is provided at the bottom of the second assembly; the top end of the adjustment stud engages and passes through the second assembly and the second ring body, and is connected to the clamping arc plate; the nut at the bottom end of the adjustment stud is located in the adjustment groove; the high-voltage cable is made to fit against the inner wall of the first ring body by adjusting the nut at the bottom end of the stud.

[0018] Optionally, the radial cross section of the clamping arc plate and the radial cross section of the second ring body are concentric circles, and the arc length of the radial cross section of the clamping arc plate is 1 / 3 to 1 / 5 of the concentric circles.

[0019] The present invention also provides a partial discharge monitoring device for a high-voltage cable, comprising a plurality of the aforementioned partial discharge monitoring components and a plurality of information transmission boxes; the current transformer in each of the partial discharge monitoring components is connected to the corresponding information transmission box via a wire; and the plurality of information transmission boxes are connected to a partial discharge monitoring host via a wireless relay.

[0020] Optionally, the connector of the information transmission box is a BNC connector, and the current transformer is connected to the BNC connector via a wire;

[0021] The information transmission box comprises: a signal sampling circuit, a processor and an antenna; the processor is connected to the BNC connector through the signal sampling circuit, and the antenna is fixed on the top of the processor.

[0022] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0023] When installing a partial discharge monitoring component, the present invention can realize the installation of the entire component by assembling the first assembly part and the second assembly part. The structure is simple and the installation is convenient. The first ring body of the first assembly part and the second ring body of the second assembly part are inserted and positioned to clamp the cable, and then the first assembly part and the second assembly part are connected and fixed, which can be assembled very quickly.

[0024] In order to improve the function of a single partial discharge monitoring component, the present invention provides a current transformer on the inner wall of the first ring body, and the current transformer is connected to the information transmission box through a wire. In this way, the single partial discharge monitoring component can process and transmit the signal monitored by the current transformer, which is beneficial to the construction of an online monitoring system; in addition, the present invention wirelessly transmits signals after improving the function of a single partial discharge monitoring component, which is beneficial to the expansion and construction of the entire monitoring system.

[0025] In addition, in order to increase the reliability after clamping and the adaptability to cables with different wire diameters, the present invention opens an adjustment groove at the bottom of the second assembly, and the top end of the stud engages and passes through the second assembly and the second ring body and extends into the top of the second ring body. The bottom end of the stud is a nut, and the nut is located in the adjustment groove; an arc-shaped clamping arc plate is installed on the top of the stud, and the clamping arc plate can be further pressed and clamped on the cable by rotating the stud, thereby improving reliability. Moreover, when the cable is of smaller specifications, it can still be clamped, and the installation of cables with different wire diameters can be reliably adapted. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0027] Figure 1 It is a structural schematic diagram of a partial discharge monitoring assembly for a high voltage cable of the present invention;

[0028] Figure 2 for Figure 1 The schematic diagram of the structure after the enlargement of A in the middle;

[0029] Figure 3 It is a schematic structural diagram of a partial discharge monitoring device for a high voltage cable according to the present invention.

[0030] Numbers in the figure: 1-partial discharge monitoring component, 2-information transmission box, 3-processor, 4-BNC connector, 5-conductor, 6-first ring body, 7-first assembly, 8-positioning groove, 9-current transformer, 11-positioning column, 12-adjusting stud, 13-clamping arc plate, 14-nut, 15-adjusting groove, 16-second ring body, 17-second assembly;

[0031] 20-assembly block, 21-latch pin, 22-assembly slot, 23-jack, 24-stopper, 25-fixed stopper, 26-spring, 27-slot body;

[0032] 31-filter, 32-signal amplification and adopting circuit, 34-antenna, 35-battery, 36-wireless relay, 37-partial discharge monitoring host. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] Figure 1 FIG. 1 is a schematic diagram of the structure of a partial discharge monitoring assembly for a high-voltage cable according to the present invention, wherein the partial discharge monitoring assembly is used to be assembled on a high-voltage cable to be monitored. Figure 1 As shown, it includes: a first assembly 7, a second assembly 17 and a current transformer 9.

[0036] The first assembly 7 and the second assembly 17 are detachably connected. In the present invention, the first assembly 7 and the second assembly 17 are connected by plugging, and are radially fixed by the plug pin 21 after plugging. Figure 1 and Figure 2As shown, the edge of the first assembly 7 is provided with an assembly block 20, and the edge of the second assembly 17 is correspondingly provided with an assembly groove 22, and the assembly block 20 is axially inserted into the assembly groove 22 to achieve the positioning of the two. The assembly block 20 is radially provided with a plug hole 23, and the plug pin 21 radially passes through the plug hole 23 of the assembly block 20 and extends into the assembly groove 22 to achieve the fixation of the assembly block 20 and the assembly groove 22. In order to further improve the convenience of installation and unloading between the first assembly 7 and the second assembly 17, the present invention further provides a groove body 27 at the position corresponding to the plug pin 21 on the side of the second assembly 17, and two stoppers 24 are fixed on both sides of the inner wall at the opening of the groove body 27, and a plug hole is provided at the bottom of the groove body 27. The top end of the plug pin 21, that is, the end away from the assembly groove 22, is connected to the fixed baffle, and the bottom end of the plug pin 21 passes through the plug hole at the bottom of the groove body 27 and is inserted into the assembly block 20. A spring 26 is sleeved on the latch pin 21 , and the spring 26 is located between the fixed baffle and the bottom of the slot body 27 .

[0037] The fixed baffle is a rectangular parallelepiped structure, the height of the fixed baffle 25 (i.e., the length of the rectangular surface of the fixed baffle connected to the latch 21) is greater than the distance between the two blocks 24, and the width of the fixed baffle 25 (i.e., the width of the rectangular surface of the fixed baffle connected to the latch 21) is less than the distance between the two blocks 24. When the fixed baffle is located in the slot 27 and between the block 24 and the bottom of the slot 27, the latch 21 is inserted into the assembly block 20, at which time the spring 26 is in a compressed state, and the spring 26 pushes the fixed baffle 25 toward the surface of the block 24, so that the fixed baffle 25 fits with the block 24; when the fixed baffle is located outside the slot 27, the latch 21 is pulled out of the assembly block 20. After the assembly block 20 of the present invention is inserted into the assembly slot 22, it is fixed by the latch 21 passing through the rear limit, and the whole process is achieved by rotating and pressing the baffle, which is very simple and reliable, and therefore very helpful for quick assembly. Specifically, the fixed baffle 25 is rotated to the direction between the two stoppers 24 and then pressed in, so that the pin 21 is inserted into the insertion hole 23 and then placed in the assembly groove 22, and then the fixed baffle 25 is rotated to the height direction and then released, at this time, the spring 26 presses the fixed baffle 25 to contact the inner surface of the stopper 24, and the stopper 24 limits the fixed baffle 25. The loosening process is the opposite process, so both disassembly and assembly are relatively fast.

[0038] For the convenience of adjustment, the fixed baffle 25 is provided with a slotted groove at the end surface away from the assembly groove 22 (i.e., the cross section close to the stopper 24), and the latch 21 can rotate freely. The latch 21 can rotate freely to insert or leave the socket 23, and the fixed baffle 25 can be adjusted to the required limit position or release position.

[0039] The first assembly 7 is provided with a first ring body 6, and the second assembly 17 is provided with a second ring body 16; the radial cross-sections of the first ring body 6 and the second ring body 16 are both semicircular, and the radial cross-sections are concentric circles. The first ring body 6 and the second ring body 16 are arranged opposite to each other and positioned by plugging, so as to form a passage allowing the high-voltage cable to pass through. Specifically, the first ring body 6 includes a positioning column 11, and the second ring body 16 includes a positioning groove 8 matching the positioning column 11, and the positioning column 11 is plugged into the positioning groove 8. The cross-sections of the positioning column 11 and the positioning groove 8 are both circular, and the cross-sectional radius of the positioning column 11 is smaller than the cross-sectional radius of the positioning groove 8. The matching structure of the positioning hole and the positioning groove 8 allows the first ring body 6 to be reliably and accurately docked with the second ring body 16, so as to achieve the best quick clamping assembly effect.

[0040] The current transformer 9 is fixed to the inner wall of the first ring body 6. In order to improve the monitoring accuracy of the current transformer 9 on the high-voltage cable, the partial discharge monitoring assembly of the present invention also includes an adjustment stud 12 and a clamping arc plate 13 with an arc structure; the clamping arc plate 13 is located in the channel formed by the first ring body 6 and the second ring body 16, and the clamping arc plate 13 is used to carry the high-voltage cable in the channel. An adjustment groove 15 is provided at the bottom of the second assembly 17; the top end of the adjustment stud 12 is engaged and passes through the second assembly 17 and the second ring body 16, and is connected to the clamping arc plate 13; the nut at the bottom end of the adjustment stud 12 is located in the adjustment groove 15; the high-voltage cable is fitted to the inner wall of the first ring body 6 by adjusting the nut at the bottom end of the stud. The arc length of the clamping arc plate 13 is 1 / 3 circle to 1 / 5 circle, and a straight groove is provided on the lower surface of the nut 14. The present invention limits the concentric circles of the clamping arc plate 13 in order to achieve a better cable clamping effect; the slotted groove of the nut 14 can be very conveniently tightened or loosened by a common slotted screwdriver or a slotted related tool. The clamping arc plate 13 with an arc structure is installed on the top of the stud. By rotating the stud, the clamping arc plate 13 can further clamp the cable, thereby improving reliability. Moreover, when the cable is of smaller specifications, it can still be clamped, and it can reliably adapt to the installation of cables with different wire diameters. In the present invention, the connection between the stud and the clamping arc plate 13 is a freely rotating connection. In this way, the rotation of the stud can cause the stud to move, and the clamping arc plate 13 does not rotate with the stud.

[0041] When installing the partial discharge monitoring component of the present invention, the entire component can be installed by assembling the first assembly 7 and the second assembly 17. The structure is simple and the installation is convenient. After the first ring body 6 of the first assembly 7 and the second ring body 16 of the second assembly 17 are positioned through the positioning groove 8 and the positioning hole, the cable is clamped and the first assembly 7 and the second assembly 17 are fixedly connected by the structure of the pin 21, which can be assembled very quickly.

[0042] Based on the above partial discharge monitoring assembly, the present invention also provides a partial discharge monitoring device for a high voltage cable. Figure 3 FIG. 1 is a schematic diagram of the structure of the partial discharge monitoring device for high voltage cables of the present invention. Figure 3 and Figure 1 As shown, the partial discharge monitoring device for a high-voltage cable of the present invention comprises a plurality of partial discharge monitoring components assembled on the high-voltage cable to be monitored. Figure 1-Figure 2 The partial discharge monitoring assembly shown. Each partial discharge monitoring assembly corresponds to an information transmission box 2. For each partial discharge monitoring assembly, the current transformer 9 arranged in contact with the inner wall of the first ring body 6 is connected to the BNC connector 4 on the top of the first assembly 7 through a wire 5, and the information transmission box 2 is fixedly installed on the top of the first assembly 7, and the BNC connector 4 is fixed on the information transmission box 2. The information transmission box 2 is also provided with a processor 3 and an antenna 34 for transmitting signals. The information transmission box 2 is connected to the partial discharge monitoring host 37 through a wireless relay 36; the partial discharge monitoring host 37 is arranged in the substation monitoring room; the wireless relay 36 is arranged at the installation site of the partial discharge monitoring assembly, and the wireless relay is used to transfer the wireless signal transmitted by the partial discharge monitoring assembly to the final substation partial discharge monitoring host, so that the real-time online monitoring information of the monitored cable can be monitored in the substation monitoring room.

[0043] Specifically, Figure 3 As shown, a filter 31 is electrically connected to the BNC connector 4 in the information transmission box 2, and the filter 31 is electrically connected to the signal amplification and sampling circuit 32, and the signal amplification and sampling circuit 32 is electrically connected to the processor 3; a battery 35 is also provided in the information transmission box 2; and the antenna 34 is installed on the top of the processor 3. The information transmission box 2 is made of stainless steel; the model of the processor 3 is stc89c51; and the current transformer 9 is a Pearson pulse current transformer. The processor 3 can filter, amplify and sample the signal of the current transformer 9 at the front end, and the final partial discharge monitoring waveform can be viewed on the display in the monitoring room.

[0044] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0045] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A partial discharge monitoring component for a high voltage cable, characterized in that: include: A first assembly, a second assembly, an information transmission box, an adjustment stud, a clamping arc plate of an arc structure, and a current transformer; The first assembly and the second assembly are detachably connected; a first ring body is provided on the first assembly, and a second ring body is provided on the second assembly; the radial cross-section of the first ring body and the radial cross-section of the second ring body are both semicircular; the first ring body and the second ring body are arranged opposite to each other and positioned by plugging, so as to form a passage allowing the high-voltage cable to pass through; The clamping arc plate is located in the channel formed by the first ring body and the second ring body, and the clamping arc plate is used to carry the high-voltage cable in the channel; An adjustment groove is provided at the bottom of the second assembly; the top end of the adjustment stud is engaged and passes through the second assembly and the second ring body, and is connected to the clamping arc plate; the nut at the bottom end of the adjustment stud is located in the adjustment groove; the high-voltage cable is fitted to the inner wall of the first ring body by adjusting the nut at the bottom end of the stud; The first ring body includes a positioning post, and the second ring body includes a positioning groove matching the positioning post, and the positioning post is inserted into the positioning groove; The first assembly and the second assembly are connected by plugging and are radially fixed by a latch after plugging; The first assembly member includes an assembly block, and the second assembly member includes an assembly groove; the assembly block is axially inserted into the assembly groove; the assembly block is radially provided with an insertion hole, and the latch radially passes through the insertion hole of the assembly block and extends into the assembly groove; The second assembly piece is further provided with a slot body, and the slot body is located on the side of the assembly slot; Two stoppers are fixed on both sides of the inner wall of the opening of the slot body, and a plug hole is provided at the bottom of the slot body; the top end of the plug is connected to the fixed baffle, and the bottom end of the plug passes through the plug hole at the bottom of the slot body and is inserted into the assembly block; a spring is sleeved on the plug, and the spring is located between the fixed baffle and the bottom of the slot body; The fixed baffle is a rectangular parallelepiped structure, and the length of the rectangular surface of the fixed baffle connected to the latch is greater than the distance between the two stoppers, and the width is less than the distance between the two stoppers; when the fixed baffle is located in the slot body and between the stopper and the bottom of the slot body, the spring is in a compressed state, and the latch is inserted into the assembly block; When the fixed baffle is located outside the slot body, the latch is pulled out of the assembly block; The information transmission box comprises: a signal sampling circuit, a processor and an antenna; The information transmission box is connected to the partial discharge monitoring host via a wireless relay; The current transformer is fixed to the inner wall of the first ring body.

2. The partial discharge monitoring assembly for high voltage cables according to claim 1, characterized in that: The cross sections of the positioning column and the positioning groove are both circular, and the cross section radius of the positioning column is smaller than the cross section radius of the positioning groove.

3. The partial discharge monitoring assembly for high voltage cables according to claim 1, characterized in that: The radial cross section of the clamping arc plate and the radial cross section of the second ring body are concentric circles, and the arc length of the radial cross section of the clamping arc plate is 1 / 3 to 1 / 5 of the concentric circles.

4. A partial discharge monitoring device for a high voltage cable, characterized in that: It comprises a plurality of partial discharge monitoring components according to any one of claims 1 to 3 and a plurality of information transmission boxes; the current transformer in each of the partial discharge monitoring components is connected to the corresponding information transmission box through a wire; The plurality of information transmission boxes are connected to the partial discharge monitoring host via wireless relays.

5. The partial discharge monitoring device for high voltage cables according to claim 4, characterized in that: The connector of the information transmission box is a BNC connector, and the current transformer is connected to the BNC connector via a wire; The information transmission box comprises: a signal sampling circuit, a processor and an antenna; the processor is connected to the BNC connector through the signal sampling circuit, and the antenna is fixed on the top of the processor.

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