Anti-torsion crosslinked polyethylene insulated power cable

Abstract

The invention discloses an anti-torsion cross-linked polyethylene insulated power cable applied to the field of cables, which comprises a petal framework composite structure comprising hollow strips, a main support layer and a buffer layer, and an outer layer protection structure formed by branch protection rings and an elastic metal net. The problems that in the prior art, a cable is prone to structural damage and performance degradation under the torsion working condition are solved, a main supporting layer in a petal framework disperses torsion stress through deformation, a buffer layer absorbs impact energy, a hollow supporting layer provides structural rigidity, and the main supporting layer, the buffer layer and the hollow supporting layer form an elastic supporting-buffer energy absorption-rigid stability synergistic system; therefore, the cable with the petal framework composite structure has excellent torsion resistance. And meanwhile, dynamic heat dissipation and temperature regulation and control are realized through fluid circulation of the hollow supporting layer and the sensing array, and the structural integrity and transmission stability of the wire core under complex working conditions are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of cables, and particularly to a torsion-resistant cross-linked polyethylene insulated power cable. Background Technology

[0002] Cross-linked polyethylene (XLPE) insulated power cables use XLPE as the insulation material, possessing excellent electrical properties, heat resistance, and mechanical strength. Their operating temperature can reach 90℃, and the allowable temperature during short circuits can reach up to 250℃. They feature high insulation resistance and low dielectric loss, making them suitable for high-voltage and ultra-high-voltage power transmission. These cables are compact, lightweight, and easy to lay. They are resistant to chemical corrosion and do not spread flames, making them widely used in urban power grids, industrial enterprises, and rail transportation. They are key equipment for achieving efficient and safe power transmission in modern power systems, especially excelling in high-load, long-distance transmission scenarios.

[0003] Chinese invention CN116978613B discloses an anti-bending and torsion cable. This invention utilizes a spring-loaded layer with a telescopic rod and a first return spring. The first and second magnetic blocks have the same magnetic poles on opposite sides, forming a repulsive force. After the cable is bent and torsioned, the telescopic rod and the first return spring are squeezed and deformed. At the same time, the repulsive force between the first and second magnetic blocks can reduce the external force transmitted to the outer sheath, thus protecting the conductor. Furthermore, through its restorative property, the cable can quickly return to its original shape after bending and torsion, solving the problem of easy deformation.

[0004] Chinese invention CN114005584B discloses an anti-torsion shielded control cable. This invention utilizes the sequential circumferential deflection of multiple movable units to eliminate the tension on the shielding layer caused by cable torsion, ensuring that the shielding layer has a long service life under frequent torsion and stretching conditions.

[0005] Currently, existing cross-linked polyethylene (XLPE) insulated power cables are prone to internal structural damage during actual use, especially under complex mechanical conditions such as torsion and bending. This is due to limitations in their material properties and structural design, leading to issues like insulation cracking and conductor displacement. These problems severely impact the long-term reliability of the cables. Furthermore, due to their overall structural design, these cables generally have limited heat dissipation capabilities. Heat tends to accumulate between the conductor and insulation layer, making effective heat dissipation difficult and resulting in significant temperature rises. This limits their ability to operate under prolonged high-load conditions and may further accelerate material aging, affecting the stability and safety of the power system. Summary of the Invention

[0006] The core of this invention lies in solving the problem of structural damage to cables under torsional conditions in existing technologies through a composite structure design of a petal-shaped skeleton and an outer protective layer. Simultaneously, the petal-shaped skeleton has an active heat dissipation function to assist in heat dissipation of the wire core.

[0007] To solve the above problems, the present invention adopts the following technical solution.

[0008] A torsion-resistant cross-linked polyethylene insulated power cable includes a petal skeleton through which wire cores are threaded. The petal skeleton includes an inner protective tube that matches the wire cores. Multiple evenly distributed hollow strips are fixedly connected to the inner protective tube. A main support layer is fixedly connected to the middle of the hollow strips. A buffer layer and a hollow support layer are respectively connected between the upper and lower ends of the main support layer and the inner wall of the hollow strips.

[0009] A partition layer is provided between two adjacent hollow strips. The partition layer includes an embedded strip with a flexible filling layer connected to it. A flow channel communicating with at least one hollow support layer is provided in the embedded strip.

[0010] The outer end of the petal skeleton is covered with an outer insulating layer that covers multiple partition layers. Multiple protective rings are installed on the outer insulating layer. Each protective ring includes a main ring body. Multiple docking units that match the partition layers are fixedly connected to the main ring body. One end of each docking unit penetrates the outer insulating layer and is inserted into the flexible filling layer. A flow guide ring is connected between the multiple docking units. One end of each docking unit inserted into the flexible filling layer is connected to a guide tube, and the guide tube communicates with the flow guide channel of the embedded strip. At least one docking unit is connected to a conduit for fluid input or output.

[0011] Furthermore, an elastic metal mesh covering the outer insulation layer is connected between two adjacent protective rings. A spiral corrugated pipe is provided on the outside of the elastic metal mesh, and a flexible buffer layer is laid between the elastic metal mesh and the outer insulation layer.

[0012] Furthermore, a strip-shaped groove is provided at the top center of the hollow strip, and a reinforcing tube is inserted between the strip-shaped groove and the outer insulation layer. The portion of the reinforcing tube on the surface of the outer insulation layer forms a rope knot and is used to fix the elastic metal mesh.

[0013] Furthermore, the inner protective tube is made of thermally conductive material, while the flexible filling layer and the main support layer are both made of flame-retardant material.

[0014] Furthermore, the buffer layer is filled with buffering material and anti-corrosion powder, and the main support layer is made of elastic material.

[0015] Furthermore, the main support layer, buffer layer, and hollow support layer are integrated into a single structure. Reinforcing pipelines are installed inside the main support layer, and pressure sensor arrays connected to the docking unit are installed on the reinforcing pipelines.

[0016] Furthermore, the hollow support layer is in the shape of a hollow tube, and multiple evenly distributed support units are arranged inside the hollow support layer. A temperature sensor that is signal-connected to the docking unit is also arranged inside the hollow support layer.

[0017] Furthermore, a partition layer is used to separate two adjacent hollow strips, and a flexible filling layer is filled between the inner strip and the outer insulation layer.

[0018] Furthermore, it also includes an auxiliary protection system, which includes a data acquisition module, a data processing module, and a control module. The data processing module is used to analyze and process the monitoring data acquired by the data acquisition module and generate control commands based on the analysis results. The control module is used to control the operation of associated equipment according to the commands issued by the data processing module to regulate the cooling of the core by the fluid supplied to the hollow support layer.

[0019] Compared with the prior art, the advantages of this invention are:

[0020] (1) In this scheme, the main support layer in the petal skeleton disperses torsional stress through deformation, the buffer layer absorbs impact energy, and the hollow support layer provides structural rigidity. The three form a synergistic system of "elastic support-buffering energy absorption-rigid stability", which makes the cable with the petal skeleton composite structure of this scheme have excellent anti-torsion performance. At the same time, the rigid embedded strip of the partition layer resists lateral compression, and the protective ring forms circumferential constraint through the docking unit, further limiting torsional deformation.

[0021] (2) The hollow support layer is connected to the flow channel of the protective ring, which can input cooling fluid and heat exchange with the inner protective tube made of heat-conducting material for efficient heat dissipation; it can also be combined with the pressure sensor array of the main support layer and the temperature sensor of the hollow support layer to coordinate with the auxiliary protection system to regulate the fluid flow and temperature, ensuring that the core works in a suitable temperature range. Attached Figure Description

[0022] Figure 1 This is a partial perspective view of the present invention;

[0023] Figure 2 for Figure 1 Schematic diagram of the structure at point A;

[0024] Figure 3 This is a cross-sectional view of the petal skeleton of the present invention;

[0025] Figure 4 This is a cross-sectional view of the retaining ring of the present invention;

[0026] Figure 5 This is a partial half-sectional view of the second embodiment of the present invention;

[0027] Figure 6 for Figure 5 A partial half-section view at point B in the middle;

[0028] Figure 7 This is a schematic diagram showing the connection between the auxiliary protection system of the present invention and the cable.

[0029] Explanation of the labels in the diagram:

[0030] 1. Core wire; 2. Petal skeleton; 21. Inner protective tube; 22. Hollow strip; 23. Main support layer; 24. Buffer layer; 25. Hollow support layer; 3. Partition layer; 31. Embedded strip; 32. Flexible filling layer; 4. Outer insulation layer; 5. Separating ring; 51. Main ring body; 52. Connecting unit; 53. Guide ring; 54. Guide tube; 6. Reinforced pipeline; 7. Elastic metal mesh. Detailed Implementation

[0031] The technical solutions will now be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention.

[0032] First implementation method:

[0033] Please see Figures 1-6 A torsion-resistant cross-linked polyethylene insulated power cable includes a petal-shaped skeleton 2 through which a conductor 1 passes. The petal-shaped skeleton 2 includes an inner protective tube 21 that matches the conductor 1. Multiple evenly distributed hollow strips 22 are fixedly connected to the inner protective tube 21. A main support layer 23 is fixedly connected to the middle of the hollow strips 22. A buffer layer 24 and a hollow support layer 25 are respectively connected between the upper and lower ends of the main support layer 23 and the inner wall of the hollow strips 22. The inner protective tube 21 is made of a thermally conductive material, and the flexible filling layer 32 and the main support layer 23 are both made of flame-retardant material. The buffer layer 24 is filled with buffer material and anti-corrosion powder, and the main support layer 23 is made of an elastic material. The main support layer 23, the buffer layer 24, and the hollow support layer 25 are an integral structure.

[0034] A partition layer 3 is provided between two adjacent hollow strips 22. The partition layer 3 includes an embedded strip 31, on which a flexible filling layer 32 is connected. The embedded strip 31 has a flow channel that communicates with at least one hollow support layer 25. The partition layer 3 is used to separate two adjacent hollow strips 22. The flexible filling layer 32 fills the space between the embedded strip 31 and the outer insulation layer 4.

[0035] The partition layer 3 between adjacent hollow strips 22 includes an embedded strip 31 made of rigid material, which can effectively resist lateral compression during torsion; the flexible filling layer 32 on the outside of the embedded strip 31 fills the gaps and absorbs part of the stress through deformation during torsion, while maintaining the compactness of the structure.

[0036] The outer end of the petal skeleton 2 is covered by an outer insulation layer 4 that covers multiple partition layers 3. Multiple protective rings 5 ​​are installed on the outer insulation layer 4, and a sufficiently long spacing is provided between adjacent protective rings 5. The specific spacing length is set by those skilled in the art according to the actual scenario and requirements to avoid excessive stress on the protective rings 5 ​​when the cable bends. The protective ring 5 includes a main ring body 51, and multiple docking units 52 that match the partition layers 3 are fixedly connected to the main ring body 51. One end of the docking unit 52 penetrates the outer insulation layer 4 and is inserted into the flexible filling layer 32. A guide ring 53 is connected between the multiple docking units 52. The end of the docking unit 52 inserted into the flexible filling layer 32 is connected to a guide ring. The conduit 54 is connected to the flow channel of the inner strip 31. At least one docking unit 52 is connected to a conduit for fluid input or output. The conduit is connected to an external fluid supply system. The conduit communicates with multiple inner strips 31 through the guide tube 54, allowing fluid to flow in the hollow support layer 25. The fluid used in this solution is a fluid for cooling the core 1, including but not limited to low-temperature inert gas, dry clean air or coolant. The appropriate fluid and fluid supply system in the prior art are selected by those skilled in the art and set up. When the core 1 is overheated, a suitable cooling fluid can be introduced to assist in cooling the core 1 and prevent the cable from failing due to overheating.

[0037] The docking unit 52 is provided with a pipe connector for connecting the conduit and an electrical connector for connecting to an external system. Suitable pipe connectors and electrical connectors from the prior art can be selected and installed on the docking unit 52 by those skilled in the art.

[0038] The hollow strip 22 of the petal skeleton 2 contains a main support layer 23 made of elastic material, with a buffer layer 24 and a hollow support layer 25 connected to its upper and lower ends, respectively, forming a composite structure of "elastic support + buffer energy absorption". When the cable is subjected to torsional force, the main support layer 23 disperses the stress through elastic deformation, and the buffer material in the buffer layer further absorbs the torsional impact, reducing the impact on the conductor 1; moreover, the main support layer 23, the buffer layer 24 and the hollow support layer 25 are designed as an integral unit to avoid relative displacement between layers and improve the torsional stability of the structure.

[0039] When the cable is subjected to external torsional force, the protective ring 5 installed on the outer insulation layer 4 disperses part of the stress to the partition layer 3 through its docking unit 52. The main ring body 51 of the protective ring 5 plays an overall clamping role. Multiple docking units 52 are inserted into the flexible filling layer 32 and together with the embedded strip 31 resist lateral compression, preventing adjacent hollow strips 22 from getting too close or misaligned when twisted.

[0040] The inner strip 31 in the partition layer 3 is made of rigid material, which directly bears and resists the lateral compressive force during torsion. The flexible filling layer 32 on its outer side fills the gaps and further absorbs some stress through its own deformation during torsion, while maintaining the structural compactness between the petal skeleton 2 and the outer insulation layer 4 and preventing the internal structure from loosening.

[0041] The torsional force is further transmitted to the petal skeleton 2. The main support layer 23 inside the hollow strip 22 serves as the core of elastic support. Because it is made of elastic material, it disperses the torsional stress through its own elastic deformation, avoiding stress concentration. The buffer layer 24 at the upper and lower ends of the main support layer 23 and the hollow support layer 25 work together. When the buffer material in the buffer layer 24 is compressed, it absorbs the torsional impact and reduces the direct impact on the core 1. The hollow support layer 25 provides a certain structural rigidity. The integrated design with the main support layer 23 and the buffer layer 24 avoids relative displacement between layers and further improves the torsional stability of the structure.

[0042] When the cable of this solution is subjected to impact, the outer insulation layer 4 first constrains the deformation through the main ring 51 of the protective ring 5 and the docking unit 52. The flexible filling layer 32 compresses and dissipates energy synchronously, and the inner strip 31 provides rigid support to prevent local collapse. After the impact energy is attenuated by the partition layer 3, it is supported by the hollow strip 22 of the petal skeleton 2. The main support layer 23 elastically rebounds and buffers, the buffer layer 24 further absorbs the residual kinetic energy, and the hollow support layer 25 maintains the structural integrity, ultimately protecting the core 1 from mechanical damage.

[0043] When the cable is working normally or when temperature regulation is required, fluid is introduced through the conduit connected to the protective ring 5. The fluid enters the flow channels of multiple inner strips 31 through multiple guide tubes 54, and then flows in multiple hollow support layers 25. Since the inner protective tube 21 is made of thermally conductive material, the fluid can exchange heat with the inner protective tube 21 when flowing in the hollow support layer 25, which helps the core 1 dissipate heat or maintain the temperature under certain conditions. The fluid after heat exchange is output through the conduit on another protective ring 5.

[0044] Under the protection of the inner protective tube 21 of the petal skeleton 2, the torsional stress and impact on the core 1 are significantly reduced due to the synergistic anti-torsion, buffering and heat dissipation effects of the above-mentioned multi-layer structure, and the overheating of the cable is easily avoided, thereby ensuring the structural integrity of the core 1 and the stability of power transmission.

[0045] Second implementation method:

[0046] The difference between this implementation method and the first implementation method is that:

[0047] Please see Figures 5-6An elastic metal mesh 7 covering the outer insulation layer 4 is connected between two adjacent protective rings 5. A spiral corrugated pipe is provided on the outside of the elastic metal mesh 7, and a flexible buffer layer is laid between the elastic metal mesh 7 and the outer insulation layer 4.

[0048] A strip-shaped groove is provided at the top center of the hollow strip 22. A reinforcing tube 6 is inserted between the strip-shaped groove and the outer insulation layer 4. The part of the reinforcing tube 6 on the surface of the outer insulation layer 4 forms a rope knot and is used to fix the elastic metal mesh 7. The reinforcing tube 6 at the top of the hollow strip 22 passes through the outer insulation layer 4 to form a rope knot, which fixes the position of the elastic metal mesh 7 and prevents it from slipping when twisted.

[0049] The elastic metal mesh 7 between adjacent protective rings 5 ​​covers the outer insulation layer 4, and the spiral corrugated tube on its outer side provides radial support. The two work together to resist the tensile and compressive stresses generated by torsion.

[0050] When the cable in this design is subjected to external torsional force, the outermost spiral corrugated tube first provides initial radial support to resist the tensile and compressive stresses generated by torsion. The elastic metal mesh 7 inside the spiral corrugated tube deforms accordingly, and the flexible buffer layer between it and the outer insulation layer 4 absorbs part of the torsional impact. At the same time, the elastic metal mesh 7 is fixed by the rope knot formed by the reinforcing tube 6 at the top of the hollow strip 22 to prevent slippage during torsion and ensure structural stability.

[0051] The third implementation method:

[0052] Please see Figures 6-7 The main support layer 23 is equipped with a pressure sensor array that is signal-connected to the docking unit 52. The pressure sensor array includes multiple uniformly distributed pressure sensors. The hollow support layer 25 is in the shape of a hollow tube. The hollow support layer 25 is equipped with multiple uniformly distributed support units. The hollow support layer 25 is equipped with a temperature sensor that is signal-connected to the docking unit 52. The pressure sensor array and the temperature sensor are not shown in the figure. The pressure sensor array and the temperature sensor both adopt existing technology. Those skilled in the art can select suitable sensors from the existing technology for setting.

[0053] It also includes an auxiliary protection system, which comprises a data acquisition module, a data processing module, and a control module;

[0054] The data acquisition module is used to collect monitoring data during cable operation; the monitoring data specifically includes: monitoring the stress change data generated by the main support layer 23 when the cable is subjected to external forces such as torsion and impact through the pressure sensor array in the main support layer 23;

[0055] Temperature data of the fluid inside the hollow support layer 25 and the surrounding environment are collected by temperature sensors installed inside the hollow support layer 25.

[0056] The data processing module is used to analyze and process the monitoring data collected by the data acquisition module, and generate control commands based on the analysis results. The data processing methods include: preprocessing the data such as filtering and noise reduction to ensure the accuracy and reliability of the data; then, the processed data is analyzed according to preset thresholds and algorithm models; for example, when the temperature sensor detects that the temperature near core 1 exceeds the set safety threshold, or when the pressure sensor array determines that the cable is under a specific working load and may be accompanied by high heat generation, the data processing module will send corresponding preset control commands to the control module.

[0057] The control module is used to control the operation of the associated equipment according to the instructions issued by the data processing module to regulate the cooling of the core 1 by the fluid supplied to the hollow support layer 25; the associated equipment includes devices for regulating the fluid input or output and a fluid supply system, which are installed by those skilled in the art using suitable equipment from the prior art, such as centrifugal pumps; specific control operations include regulating the fluid input or output by controlling the fluid supply system or devices connected to the control conduit.

[0058] When enhanced heat dissipation is required, the control module instructs the external fluid supply system or equipment to increase the fluid flow rate or decrease the initial fluid temperature. During the fluid flow within the hollow support layer 25, it undergoes thorough heat exchange with the inner protective tube 21, made of thermally conductive material, absorbing the heat generated by the conductor 1. The heat is then carried out of the cable via the output conduit, thus achieving effective heat dissipation for the conductor 1. If the temperature falls below a certain set value or active heat dissipation is not required, the control module instructs a reduction in fluid flow rate or suspends fluid supply to optimize energy consumption or meet specific operating conditions. Through this dynamic control mechanism, the auxiliary protection system ensures that the conductor 1 always operates within a suitable temperature range, guaranteeing the safe and stable operation of the cable.

[0059] The above description is merely a preferred embodiment of the present invention; it encompasses all the protection scope of the present invention. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solutions and improved concepts of the present invention, should be covered within the protection scope of the present invention.

Claims

1. A torsion-resistant cross-linked polyethylene insulated power cable, comprising a petal-shaped skeleton (2) through which cores (1) are threaded, characterized in that: The petal skeleton (2) includes an inner protective tube (21) that matches the wire core (1). superior Multiple evenly distributed hollow strips (22) are fixedly connected. A main support layer (23) is fixedly connected to the middle of the hollow strip (22). A buffer layer (24) and a hollow support layer (25) are respectively connected between the upper and lower ends of the main support layer (23) and the inner wall of the hollow strip (22). A partition layer (3) is provided between two adjacent hollow strips (22). The partition layer (3) includes an embedded strip (31). A flexible filling layer (32) is connected to the embedded strip (31). A flow channel communicating with at least one hollow support layer (25) is opened in the embedded strip (31). The outer end of the petal skeleton (2) is covered with an outer insulating layer (4) covering multiple partition layers (3). Multiple protective rings (5) are installed on the outer insulating layer (4). Each protective ring (5) includes a main ring body (51). Multiple docking units (52) matching the partition layers (3) are fixedly connected to the main ring body (51). One end of each docking unit (52) penetrates the outer insulating layer (4) and is inserted into the flexible filling layer (32). A flow guide ring (53) is connected between the multiple docking units (52). One end of each docking unit (52) inserted into the flexible filling layer (32) is connected to a guide tube (54), and the guide tube (54) communicates with the flow channel of the embedded strip (31). At least one docking unit (52) is connected to a conduit for fluid input or output.

2. The torsion-resistant cross-linked polyethylene insulated power cable according to claim 1, characterized in that: An elastic metal mesh (7) covering the outer insulation layer (4) is connected between two adjacent protective rings (5). A spiral corrugated pipe is provided on the outside of the elastic metal mesh (7). A flexible buffer layer is laid between the elastic metal mesh (7) and the outer insulation layer (4).

3. The torsion-resistant cross-linked polyethylene insulated power cable according to claim 2, characterized in that: A strip-shaped groove is provided at the top center of the hollow strip (22), and a reinforcing tube (6) is inserted between the strip-shaped groove and the outer insulation layer (4). The portion of the reinforcing tube (6) on the surface of the outer insulation layer (4) forms a rope knot and is used to fix the elastic metal mesh (7).

4. The torsion-resistant cross-linked polyethylene insulated power cable according to claim 3, characterized in that: The inner protective tube (21) is made of thermally conductive material, the flexible filling layer (32) and the main support layer (23) are both made of flame-retardant material, and the inner strip (31) is made of rigid material.

5. A torsion-resistant cross-linked polyethylene insulated power cable according to claim 4, characterized in that: The buffer layer (24) is filled with buffer material and anti-corrosion powder, and the main support layer (23) is made of elastic material.

6. The torsion-resistant cross-linked polyethylene insulated power cable according to claim 5, characterized in that: The main support layer (23), buffer layer (24) and hollow support layer (25) are an integral structure. The main support layer (23) is provided with a pressure sensing array that is connected to the docking unit (52) via signal.

7. A torsion-resistant cross-linked polyethylene insulated power cable according to claim 6, characterized in that: The hollow support layer (25) is in the shape of a hollow tube. Multiple evenly distributed support units are provided inside the hollow support layer (25). A temperature sensor that is signal-connected to the docking unit (52) is provided inside the hollow support layer (25).

8. A torsion-resistant cross-linked polyethylene insulated power cable according to claim 7, characterized in that: The partition layer (3) is used to separate two adjacent hollow strips (22), the flexible filling layer (32) is filled between the inner strip (31) and the outer insulation layer (4), and the flexible filling layer (32) covers the main support layer (23) and the corresponding area of ​​the main support layer (23).

9. A torsion-resistant cross-linked polyethylene insulated power cable according to claim 8, characterized in that: It also includes an auxiliary protection system, which includes a data acquisition module, a data processing module and a control module; the data processing module is used to analyze and process the monitoring data acquired by the data acquisition module and generate control commands based on the analysis results; the control module is used to control the operation of associated equipment according to the commands issued by the data processing module to regulate the cooling of the core (1) by the fluid supplied to the hollow support layer (25).

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