Highly durable anti-corona medium voltage cable

Abstract

The application discloses a high-durability anti-corona medium-voltage cable, the surface of a rubber protection layer is provided with positioning rubber rings at equal intervals, positioning grooves are formed in the middle part of the positioning rubber rings, an insulating rubber wrapping sleeve is sleeved at the end of the rubber protection layer, elastic rubber round sleeves are fixedly connected to the two ends of the insulating rubber wrapping sleeve, arc-shaped positioning close blocks are fixedly connected to the bottom of the end part of the elastic rubber round sleeves, splicing grooves are formed in the two ends of the top of the arc-shaped positioning close blocks, arc-shaped movable close blocks are arranged on the top of the arc-shaped positioning close blocks, splicing blocks are fixedly connected to the two ends of the arc-shaped movable close blocks, the cable joint is wrapped and protected by the insulating rubber wrapping sleeve, the cable joint is prevented from being directly exposed to the outside environment and from being in contact with air to cause a corona phenomenon, the two ends of the insulating rubber wrapping sleeve are clamped and fixed by the arc-shaped positioning close blocks and the arc-shaped movable close blocks in cooperation, the safety sealing performance is improved, and air penetration is prevented.

Description

Technical Field

[0001] This invention relates to the field of medium-voltage cable technology, specifically to a high-durability, corona-resistant medium-voltage cable. Background Technology

[0002] Medium-voltage cables are the mainstay of power transmission, designed specifically for 3-35 kV voltages. They are widely used in urban power grids, factory power distribution, and new energy transmission. Their core structure includes conductors, insulation layers, and sheaths, ensuring stable power transmission. Corona discharge, on the other hand, is a phenomenon where a charged body surface experiences partial discharge in a gaseous or liquid medium. It often occurs around high-voltage conductors and near the tips of charged bodies, producing substances such as ozone and nitrogen oxides. In substations and lines, a halo-like light layer often appears, emitting hissing or crackling sounds. Corona discharge consumes electrical energy and interferes with radio waves. In cables, the corona phenomenon can lead to gradual damage to the insulation material, thereby affecting the cable's service life and safety performance. However, the current cable joints are poorly protected, and the joints are not protected in a sealed environment, which makes the insulation material at the joints prone to aging and damage, and easily causes corona discharge. Therefore, this invention provides a high-durability anti-corona medium-voltage cable to meet people's needs. Summary of the Invention

[0003] This invention provides a high-durability anti-corona medium-voltage cable, which can effectively solve the problems mentioned in the background art, such as poor protection at the cable joint, failure to protect the joint in a sealed environment, resulting in a high probability of aging and damage of the insulation material at the joint, and easy generation of corona phenomena.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a high-durability anti-corona medium-voltage cable, comprising three cores, each of the three cores having a metal shielding layer sleeved on its surface, the surface of the three metal shielding layers being extruded and wrapped with a rubber insulation layer, the outer side of the surface of the three rubber insulation layers being sleeved with a rubber protective layer, and a joint sealing anti-corona mechanism being provided on the surface of the end of the rubber protective layer. The joint sealing anti-corona mechanism includes a positioning rubber ring sleeve; Positioning rubber rings are equidistantly installed on the surface of the rubber protective layer. Each positioning rubber ring has a positioning groove in the middle. An insulating rubber sleeve is fitted onto the end of the rubber protective layer. Both ends of the insulating rubber sleeve are fixedly connected to an elastic rubber sleeve. An arc-shaped positioning and fastening block is fixedly connected to the bottom of the end of the elastic rubber sleeve. Both ends of the top of the arc-shaped positioning and fastening block are provided with splicing grooves. An arc-shaped movable fastening block is installed on the top of the arc-shaped positioning and fastening block. Both ends of the arc-shaped movable fastening block are fixedly connected with splicing blocks. Mounting bolts are installed in the middle of the two splicing blocks.

[0005] According to the above technical solution, the diameter of the cross-section of the insulating rubber sleeve is larger than the diameter of the elastic rubber sleeve, and the elastic rubber sleeve is tightly attached to the surface of the rubber protective layer.

[0006] According to the above technical solution, both the arc-shaped positioning tight-fitting block and the arc-shaped movable tight-fitting block are movably embedded inside the positioning groove, the splicing block is embedded inside the splicing groove, and the splicing block and the arc-shaped positioning tight-fitting block are fixedly connected by mounting bolts.

[0007] Compared with the prior art, the beneficial effects of the present invention are: the present invention has a scientific and reasonable structure and is safe and convenient to use. 1. It is equipped with a joint sealing anti-corona mechanism, which uses an insulating rubber sleeve to wrap and protect the cable joint, preventing the cable joint from being directly exposed to the external environment and contacting air, thus preventing corona phenomena. It protects the cable joint by removing the medium that can generate corona. The arc-shaped positioning tight-fitting block and the arc-shaped movable tight-fitting block work together to clamp and fix the two ends of the insulating rubber sleeve, improving the safety sealing performance and preventing air penetration. Meanwhile, the positioning rubber ring and positioning groove work together to stabilize the arc-shaped positioning tight block and the arc-shaped movable tight block, preventing them from sliding and shifting when the two cables are under force. The insulating rubber sleeve, the arc-shaped positioning tight block and the arc-shaped movable tight block are tightly connected to each other, which strengthens the connection between the two cables and prevents them from being separated and falling off due to external pulling force.

[0008] 2. The interlocking groove and interlocking block work together to assist in the positioning of the arc-shaped movable tight-fitting block during installation. This ensures that the arc-shaped movable tight-fitting block and the arc-shaped positioning tight-fitting block fit tightly against each other, making installation quicker and more convenient. Furthermore, the arc-shaped movable tight-fitting block presses and fixes the extended sealing rubber strip tightly. Together with the arc-shaped positioning tight-fitting block, this ensures that the two ends of the insulating rubber sleeve are properly sealed after splicing and fixing, preventing gaps that could allow airflow to penetrate and prevent the cable joint from being properly sealed and isolated.

[0009] 3. The use of the exhaust channel and the sealing rubber piston in combination greatly facilitates the exhaust and sealing of the internal air of the insulating rubber sheath. After wrapping and covering the outside of the cable joint, the air inside is extracted to prevent excessive gas residue in the space where the joint is located, which may lead to corona discharge later.

[0010] 4. A positioning corona monitoring mechanism is provided. The triangular positioning support rubber frame and the central limiting rubber strip work together to support and position the core, so that the core maintains a certain distance inside the cable, which improves the installation stability of the core inside the cable and prevents the core from being misaligned or tilted, thus affecting the normal operation of the cable. At the same time, the plastic rubber anti-collapse layer is used to fill and support the triangular positioning support rubber frame, which plays a role in preventing collapse and compression, preventing damage to the core after being squeezed by the outside world, and the buffer protection airbag buffers the external pressure, improving the stability of the core and the triangular positioning support rubber frame.

[0011] 5. By using conductive metal strips and arc-shaped metal contact plates in combination, the insulation environment outside the core is monitored to prevent leakage discharge or corona from occurring inside the cable, which would prevent the timely acquisition of signals. In addition, the metal conductive short posts and arc-shaped metal contact plates provide a path for leakage conduction, making it convenient to use external equipment for continuous monitoring, which is more accurate and convenient. Simultaneously, the interlocking blocks and locking bolts work together to facilitate the splicing of the two side fixing blocks, ensuring they are tightly attached to the surface of the rubber protective layer. The assembled soft rubber strip provides sufficient operational flexibility for the flipping and fitting of the two side fixing blocks. The two side fixing blocks, the upper arc-shaped fixing block, and the arc-shaped sealing and fitting block work together to cover and protect the metal conductive short column and the arc-shaped metal contact guide plate, preventing them from being easily damaged by direct exposure to the external environment.

[0012] In summary, by combining the joint sealing anti-corona mechanism and the positioning corona monitoring mechanism, the cable joint is first wrapped and protected at locations prone to corona discharge due to air contact, reducing the probability of corona occurrence. Then, the operation of the cable core is monitored, which can promptly detect leakage and other issues caused by internal cable damage. This provides sufficient time for timely inspection and maintenance, thereby improving the overall safety of cable installation and use. Attached Figure Description

[0013] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0014] In the attached diagram: Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the installation structure of the insulating rubber sleeve of the present invention; Figure 3 This is a schematic cross-sectional view of the cable of the present invention; Figure 4 This is a schematic diagram of the installation structure of the extended sealing rubber strip of the present invention; Figure 5 This is a schematic diagram of the installation structure of the arc-shaped sealing and clamping strip of the present invention; Figure 6 This is a schematic diagram of the anti-corona discharge mechanism for the joint sealing of the present invention; Figure 7This is a schematic diagram of the installation structure of the support column of the present invention; Figure 8 This is a schematic diagram of the installation structure of the arc-shaped metal bonding sheet of the present invention; Figure 9 This is a schematic diagram of the positioning corona monitoring mechanism of the present invention; The diagram labels are: 1. Core; 2. Metal shielding layer; 3. Rubber insulation layer; 4. Rubber protective layer. 5. Joint sealing anti-corona mechanism; 501. Positioning rubber ring; 502. Positioning groove; 503. Insulating rubber sleeve; 504. Elastic rubber sleeve; 505. Arc-shaped positioning tight-fitting block; 506. Splicing groove; 507. Arc-shaped movable tight-fitting block; 508. Splicing block; 509. Mounting bolt; 510. Arc-shaped sealing pressure strip; 511. Extended sealing rubber strip; 512. Exhaust channel; 513. Sealing rubber piston; 6. Positioning corona monitoring mechanism; 601. Triangular positioning support rubber frame; 602. Central limiting rubber strip; 603. Support column; 604. Conductive metal strip; 605. Arc-shaped metal bonding piece; 606. Metal conduction short column; 607. Upper arc-shaped fixing block; 608. Assembly soft rubber strip; 609. Side fixing block; 610. Arc-shaped sealing bonding block; 611. Arc-shaped metal contact guide piece; 612. Tightly fitting splicing block; 613. Locking bolt; 614. Molded rubber anti-collapse layer; 615. Fiber filling layer; 616. Buffer protection airbag. Detailed Implementation

[0015] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0016] Example: Figure 1-9 As shown, the present invention provides a technical solution, a high-durability anti-corona medium-voltage cable, comprising three cores 1, each of the three cores 1 having a metal shielding layer 2 sleeved on its surface, the surface of the three metal shielding layers 2 being extruded and wrapped with a rubber insulation layer 3, the outer side of the surface of the three rubber insulation layers 3 being sleeved with a rubber protective layer 4, and the surface of the end of the rubber protective layer 4 being provided with a joint sealing anti-corona mechanism 5. The joint sealing anti-corona mechanism 5 includes a positioning rubber ring 501, a positioning groove 502, an insulating rubber sleeve 503, an elastic rubber round sleeve 504, an arc-shaped positioning tight-fitting block 505, a splicing groove 506, an arc-shaped movable tight-fitting block 507, a splicing block 508, a mounting bolt 509, an arc-shaped sealing pressure strip 510, an extended sealing rubber strip 511, an exhaust channel 512, and a sealing rubber piston 513; Positioning rubber rings 501 are equidistantly installed on the surface of the rubber protective layer 4. Positioning grooves 502 are opened in the middle of each positioning rubber ring 501. An insulating rubber sleeve 503 is sleeved on the end of the rubber protective layer 4. An elastic rubber sleeve 504 is fixedly connected to both ends of the insulating rubber sleeve 503. The diameter of the cross-section of the insulating rubber sleeve 503 is larger than the diameter of the elastic rubber sleeve 504. The elastic rubber sleeve 504 is tightly attached to the surface of the rubber protective layer 4. An arc-shaped positioning and fastening block 505 is fixedly connected to the bottom of the end of the elastic rubber sleeve 504. Both ends of the top of the arc-shaped positioning and fastening block 505 have splicing grooves 506. An arc-shaped movable fastening block 507 is installed on the top of the arc-shaped positioning and fastening block 505. Splicing blocks 508 are fixedly connected to both ends of the arc-shaped movable fastening block 507. Mounting bolts 509 are installed in the middle of both splicing blocks 508. Both the arc-shaped positioning and fastening block 505 and the arc-shaped movable fastening block 507 are movably embedded inside the positioning groove 502. The splicing block 508 is embedded in the splicing groove 506. Internally, the splicing block 508 and the arc-shaped positioning tight-fitting block 505 are fixedly connected by mounting bolts 509. The cable joint is wrapped and protected by an insulating rubber sleeve 503 to prevent the cable joint from being directly exposed to the external environment and contacting air, thus preventing corona discharge. Protection is achieved by removing the medium that can generate corona at the cable joint location. The arc-shaped positioning tight-fitting block 505 and the arc-shaped movable tight-fitting block 507 work together to clamp and fix the two ends of the insulating rubber sleeve 503, improving the safety sealing performance and preventing air penetration. Meanwhile, the positioning rubber ring 501 and the positioning groove 502 cooperate with each other to stabilize the arc-shaped positioning tight block 505 and the arc-shaped movable tight block 507, preventing the arc-shaped positioning tight block 505 and the arc-shaped movable tight block 507 from sliding and shifting when the two cables are subjected to force. The insulating rubber sleeve 503, the arc-shaped positioning tight block 505 and the arc-shaped movable tight block 507 are tightly connected to each other, which strengthens the connection of the two cables and prevents them from being separated and falling off due to external pulling force. The splicing groove 506 and splicing block 508 work together to assist in the positioning of the arc-shaped movable tight-fitting block 507 during installation. This ensures that the arc-shaped movable tight-fitting block 507 and the arc-shaped positioning tight-fitting block 505 fit tightly against each other, making installation quicker and more convenient. The arc-shaped movable tight-fitting block 507 also presses and fixes the extended sealing rubber strip 511 tightly. Together with the arc-shaped positioning tight-fitting block 505, this ensures that the two ends of the insulating rubber sleeve 503 are in a well-sealed environment after splicing and fixing, preventing gaps from causing airflow to penetrate and the cable joints from being unable to be in a sealed and isolated environment. An arc-shaped movable tight-fitting block 507 is fixedly connected to an arc-shaped sealing and pressing strip 510 at one end. An extended sealing rubber strip 511 is connected to the top of the end of the elastic rubber sleeve 504. An exhaust channel 512 is installed on the top of the insulating rubber sleeve 503. A sealing rubber piston 513 is embedded inside the exhaust channel 512. The extended sealing rubber strip 511 extends to the surface of the positioning rubber ring 501. The arc-shaped sealing and pressing strip 510 and the arc-shaped movable tight-fitting block 507 are both pressed tightly against the surface of the extended sealing rubber strip 511. The exhaust channel 512 and the sealing rubber piston 513 cooperate with each other to greatly facilitate the exhaust and sealing of the insulating rubber sleeve 503. After wrapping and covering the outside of the cable joint, the air inside is extracted to prevent too much gas residue in the space where the joint is located, which may cause corona phenomenon in the future. The rubber protective layer 4 is equipped with a positioning corona monitoring mechanism 6. The positioning corona monitoring mechanism 6 includes a triangular positioning support rubber frame 601, a central limiting rubber strip 602, a support column 603, a conductive metal strip 604, an arc-shaped metal bonding piece 605, a metal conductive short column 606, an upper arc-shaped fixing block 607, an assembly soft rubber strip 608, a side fixing block 609, an arc-shaped sealing bonding block 610, an arc-shaped metal contact guide piece 611, a tight splicing block 612, a locking bolt 613, a shaped rubber anti-collapse layer 614, a fiber filling layer 615, and a buffer protective airbag 616; A triangular positioning support rubber frame 601 is installed inside the rubber protective layer 4. Three cores 1 are equidistantly distributed inside the triangular positioning support rubber frame 601. The outer wall of the rubber insulation layer 3 is in contact with the inner wall of the triangular positioning support rubber frame 601. A central limiting rubber strip 602 is installed at the center position inside the triangular positioning support rubber frame 601. Support columns 603 are equidistantly connected to the bottom end of the central limiting rubber strip 602. Conductive metal strips 604 are embedded at the three corners of the triangular positioning support rubber frame 601. Arc-shaped metal bonding pieces 605 are attached to the surface of the three corners of the triangular positioning support rubber frame 601. Metal conductive short columns 606 are fixedly connected to the surface of the three arc-shaped metal bonding pieces 605. The positions of the three arc-shaped metal bonding pieces 605 correspond to the positions of the three conductive metal strips 604. The arc-shaped metal bonding pieces 605 are tightly attached to the surface of the conductive metal strips 604. An upper arc-shaped fixing block 607 is installed on the surface of the rubber protective layer 4. Both ends of the upper arc-shaped fixing block 607 are connected to assembly soft rubber strips 608. Side fixing blocks 609 are fixedly connected to the ends of the two assembly soft rubber strips 608. Arc-shaped sealing and bonding blocks 610 are fixedly connected to the sides of the two side fixing blocks 609 and the two sides of the upper arc-shaped fixing block 607. Arc-shaped metal contact guide plates 611 are fixedly installed on the inner walls of the upper arc-shaped fixing block 607 and the inner walls of the two side fixing blocks 609. Tightly fitting splices are connected to the bottom ends of the two side fixing blocks 609. Block 612, with a locking bolt 613 installed in the middle of the splicing block 612, the metal conductive short column 606 movably passes through the fiber filling layer 615 and the rubber protective layer 4, the positions of the three arc-shaped metal contact guides 611 correspond to the positions of the three metal conductive short columns 606, the three arc-shaped metal contact guides 611 are tightly attached to the ends of the three metal conductive short columns 606, the arc-shaped sealing bonding block 610 and the assembly soft rubber strip 608 are both tightly attached to the surface of the rubber protective layer 4, the two tightly attached splicing blocks 612 are attached to each other and locked and fixed by the locking bolt 613; The triangular positioning support rubber frame 601 is filled with a plastic rubber anti-collapse layer 614, and the rubber protective layer 4 is filled with a fiber filling layer 615. Buffer protection airbags 616 are equidistantly embedded in the fiber filling layer 615 along the circumferential direction. The triangular positioning support rubber frame 601 and the central limiting rubber strip 602 work together to support and position the core 1, ensuring that the core 1 maintains a certain distance inside the cable. This improves the installation stability of the core 1 inside the cable and prevents misalignment or tilting of the core 1 from affecting the overall normal operation of the cable. At the same time, the plastic rubber anti-collapse layer 614 is used to fill and support the triangular positioning support rubber frame 601, which plays the role of preventing collapse and squeezing, preventing the core 1 from being damaged after being squeezed by the outside. The buffer protection airbag 616 buffers the external pressure, improving the stability of the core 1 and the triangular positioning support rubber frame 601. The conductive metal strip 604 and the arc-shaped metal bonding piece 605 work together to monitor the insulation environment outside the core 1, preventing leakage discharge or corona from occurring inside the cable and thus failing to capture the signal in time. The metal conductive short post 606 and the arc-shaped metal contact conductor 611 provide a path for leakage conduction, making it convenient to use external equipment for continuous monitoring, which is more accurate and convenient. Meanwhile, the interlocking splicing block 612 and the locking bolt 613 work together to facilitate the splicing of the two side fixing blocks 609, making them fit tightly against the surface of the rubber protective layer 4. The assembled soft rubber strip 608 provides sufficient operational flexibility for the flipping and bonding of the two side fixing blocks 609. The two side fixing blocks 609, the upper arc-shaped fixing block 607 and the arc-shaped sealing bonding block 610 work together to cover and protect the metal conductive short column 606 and the arc-shaped metal contact guide plate 611, preventing them from being easily damaged by direct exposure to the external environment.

[0017] The working principle and usage process of this invention are as follows: First, during cable production, a metal shielding layer 2 and a rubber insulation layer 3 are sequentially wrapped around the surface of the three cores 1. The three cores 1 are all inserted into the interior of the triangular positioning support rubber frame 601, located at the three corners inside the triangular positioning support rubber frame 601. The outer wall of the rubber insulation layer 3 is in contact with the inner wall of the triangular positioning support rubber frame 601 and the surface of the central limiting rubber strip 602. The three cores 1 are supported and limited by the triangular positioning support rubber frame 601 and the central limiting rubber strip 602, so that the three cores 1 will not be misaligned or tilted. The interior of the triangular positioning support rubber frame 601 is filled with a plastic rubber anti-collapse layer 614, which improves the structural strength of the triangular positioning support rubber frame 601 and prevents it from being squeezed and deformed. The rubber protective layer 4 is sleeved on the outside of the triangular positioning support rubber frame 601, and the inner wall of the rubber protective layer 4 is filled with a fiber filling layer 615, and the buffer protective airbag 616 is embedded in the inside of the fiber filling layer 615. When installing and using cables, if a connection is required, align the ends of the two cables, and select a position close to the positioning rubber ring 501 for the connection. Fit one end of the insulating rubber sleeve 503 onto the surface of one cable. The elastic rubber sleeve 504 should fit snugly against the surface of the rubber protective layer 4. The arc-shaped positioning and fastening block 505 should be movably embedded inside the positioning groove 502. The extended sealing rubber strip 511 should cover the surface of the positioning rubber ring 501. Then, remove the arc-shaped movable fastening block 507 and cover the surface of the extended sealing rubber strip 511, aligning it with the position of the arc-shaped positioning and fastening block 505. Correspondingly, the arc-shaped movable tight-fitting block 507 presses down to extend the sealing rubber strip 511 into the positioning groove 502, and the bottom splicing block 508 is embedded into the splicing groove 506. The splicing block 508 and the arc-shaped positioning tight-fitting block 505 are locked and fixed by the mounting bolt 509. The arc-shaped sealing pressure strip 510 is pressed tightly on the surface of the extended sealing rubber strip 511, and one end of the insulating rubber sleeve 503 is spliced ​​and locked by the elastic rubber sleeve 504, the arc-shaped positioning tight-fitting block 505, the arc-shaped movable tight-fitting block 507 and the extended sealing rubber strip 511, thus achieving the sealing effect. Then, the insulating rubber sleeve 503 is pressed and pushed towards the fixed end, so that the ends of the two cables can be exposed, providing enough space for the connection of the two cable ends. The workers connect the ends of the two cables, and then put the insulating rubber sleeve 503 on the surface of the cable joint, so that the other end of the insulating rubber sleeve 503 can extend to the surface of the other cable. The elastic rubber sleeve 504 is tightly attached to the rubber protective layer 4 on the surface of the cable. The above operation is repeated, and the arc-shaped positioning tight-fitting block 505, the arc-shaped movable tight-fitting block 507 and the extended sealing rubber strip 511 are spliced ​​and locked to seal and fix the other end of the insulating rubber sleeve 503, so that the cable joint is in a sealed environment. Workers can pull out the sealing rubber piston 513 and use the exhaust channel 512 to squeeze or extract the air inside the insulating rubber sleeve 503 to prevent excessive air from being trapped inside the insulating rubber sleeve 503, which could easily cause corona discharge. Then, workers can reinsert the sealing rubber piston 513 into the exhaust channel 512 to keep the inside of the insulating rubber sleeve 503 sealed, thus protecting the cable joint. The insulating rubber sleeve 503, the arc-shaped positioning tight-fitting block 505, and the arc-shaped movable tight-fitting block 507 work together to improve the connection strength at the joint and prevent the joint from falling off due to the tension applied to the cable. The staff used the upper arc-shaped fixing block 607 to locate the metal conductive short column 606, and placed the upper arc-shaped fixing block 607 over the metal conductive short column 606. The arc-shaped metal contact guide plate 611 inside the upper arc-shaped fixing block 607 fits against the end of the metal conductive short column 606. Due to the softness and flexibility of the assembly soft rubber strip 608, the two side fixing blocks 609 can wrap around the surface of the rubber protective layer 4 from both sides. The two bottom tightly fitting splicing blocks 613 fit together and are locked in place using locking bolts 613. The arc-shaped metal contact guide plates 611 on the inner walls of the two side fixing blocks 609 respectively connect with the other two metal... The ends of the conductive short post 606 are attached together, and the arc-shaped sealing adhesive block 610 is tightly attached to the rubber protective layer 4, so that the metal conductive short post 606 and the arc-shaped metal contact conductor 611 are protected in a sealed environment. The arc-shaped metal contact conductor 611 is connected to the external arc leakage monitoring equipment. When leakage and arcing occur in the core 1, the rubber insulation layer 3 will be broken down. The current will be transmitted outward in sequence through the conductive metal strip 604, the arc-shaped metal adhesive block 605, the metal conductive short post 606 and the arc-shaped metal contact conductor 611, so that the staff can understand the leakage and arcing breakdown in time and repair or replace the corresponding cable in time.

[0018] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-durability corona-resistant medium-voltage cable, comprising three cores (1), characterized in that: The surfaces of the three cores (1) are all fitted with metal shielding layers (2), the surfaces of the three metal shielding layers (2) are covered with rubber insulation layers (3) by extrusion, the outer sides of the surfaces of the three rubber insulation layers (3) are fitted with rubber protective layers (4), and the surfaces of the ends of the rubber protective layers (4) are provided with joint sealing anti-corona mechanism (5). The joint sealing anti-corona mechanism (5) includes a positioning rubber ring (501). Positioning rubber rings (501) are installed at equal intervals on the surface of the rubber protective layer (4). Positioning grooves (502) are opened in the middle of each positioning rubber ring (501). An insulating rubber sleeve (503) is sleeved on the end of the rubber protective layer (4). An elastic rubber sleeve (504) is fixedly connected to both ends of the insulating rubber sleeve (503). An arc-shaped positioning and fastening block (505) is fixedly connected to the bottom of the end of the elastic rubber sleeve (504). Both ends of the top of the arc-shaped positioning and fastening block (505) are provided with splicing grooves (506). An arc-shaped movable fastening block (507) is installed on the top of the arc-shaped positioning and fastening block (505). Both ends of the arc-shaped movable fastening block (507) are fixedly connected with splicing blocks (508). Mounting bolts (509) are installed in the middle of the two splicing blocks (508). The rubber protective layer (4) is equipped with a positioning corona monitoring mechanism (6). The positioning corona monitoring mechanism (6) includes a triangular positioning support rubber frame (601). The rubber protective layer (4) is equipped with a triangular positioning support rubber frame (601), and a center limiting rubber strip (602) is installed at the center of the triangular positioning support rubber frame (601). The bottom end of the center limiting rubber strip (602) is connected with support columns (603) at equal intervals. Conductive metal strips (604) are embedded at the three corners of the triangular positioning support rubber frame (601), and arc-shaped metal bonding pieces (605) are attached to the surface of the three corners of the triangular positioning support rubber frame (601). Metal conductive short columns (606) are fixedly connected to the surfaces of the three arc-shaped metal bonding pieces (605). The surface of the rubber protective layer (4) is equipped with an upper arc-shaped fixing block (607). Both ends of the upper arc-shaped fixing block (607) are connected to assembly soft rubber strips (608). The ends of the two assembly soft rubber strips (608) are fixedly connected to side fixing blocks (609). The two sides of the two side fixing blocks (609) and the two sides of the upper arc-shaped fixing block (607) are fixedly connected to arc-shaped sealing and bonding blocks (610). The inner wall of the upper arc-shaped fixing block (607) and the inner wall of the two side fixing blocks (609) are fixedly installed with arc-shaped metal contact guide plates (611). The bottom ends of the two side fixing blocks (609) are connected to tight splicing blocks (612). The middle of the tight splicing blocks (612) is equipped with locking bolts (613). The triangular positioning support rubber frame (601) is filled with a plastic rubber anti-collapse layer (614), the rubber protective layer (4) is filled with a fiber filling layer (615), and the fiber filling layer (615) is equidistantly embedded with buffer protective airbags (616) along the circumferential direction.

2. The high-durability anti-corona medium-voltage cable according to claim 1, characterized in that, The diameter of the cross-section of the insulating rubber sleeve (503) is larger than the diameter of the elastic rubber sleeve (504), and the elastic rubber sleeve (504) is in close contact with the surface of the rubber protective layer (4).

3. A high-durability anti-corona medium-voltage cable according to claim 1, characterized in that, The arc-shaped positioning tight-fitting block (505) and the arc-shaped movable tight-fitting block (507) are both movably embedded inside the positioning groove (502), the splicing block (508) is embedded inside the splicing groove (506), and the splicing block (508) and the arc-shaped positioning tight-fitting block (505) are fixedly connected by mounting bolts (509).

4. A high-durability anti-corona medium-voltage cable according to claim 1, characterized in that, One end of the arc-shaped movable tight-fitting block (507) is fixedly connected to an arc-shaped sealing and pressing strip (510), the top of the end of the elastic rubber sleeve (504) is connected to an extended sealing rubber strip (511), the top of the insulating rubber wrapping sleeve (503) is equipped with an exhaust channel (512), and a sealing rubber piston (513) is embedded inside the exhaust channel (512).

5. A high-durability anti-corona medium-voltage cable according to claim 4, characterized in that, The extended sealing rubber strip (511) extends to the surface of the positioning rubber ring (501), and the arc-shaped sealing pressing strip (510) and the arc-shaped movable pressing block (507) are both pressed tightly against the surface of the extended sealing rubber strip (511).

6. A high-durability corona-resistant medium-voltage cable according to claim 5, characterized in that, The three cores (1) are equidistantly distributed inside the triangular positioning support rubber frame (601), and the outer wall of the rubber insulation layer (3) is in contact with the inner wall of the triangular positioning support rubber frame (601).

7. A high-durability anti-corona medium-voltage cable according to claim 6, characterized in that, The positions of the three arc-shaped metal bonding pieces (605) correspond to the positions of the three conductive metal strips (604), and the arc-shaped metal bonding pieces (605) are in close contact with the surface of the conductive metal strips (604).

8. A high-durability corona-resistant medium-voltage cable according to claim 6, characterized in that, The metal conductive short post (606) extends through the fiber filling layer (615) and the rubber protective layer (4). The positions of the three arc-shaped metal contact conductors (611) correspond to the positions of the three metal conductive short posts (606). The three arc-shaped metal contact conductors (611) are in close contact with the ends of the three metal conductive short posts (606). The arc-shaped metal contact conductors (611) are connected to the external leakage current monitoring equipment.

9. A high-durability corona-resistant medium-voltage cable according to claim 6, characterized in that, The arc-shaped sealing patch (610) and the assembled soft rubber strip (608) are both tightly attached to the surface of the rubber protective layer (4). The two tightly attached splicing blocks (612) are attached to each other and locked and fixed by locking bolts (613).

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