Wind cable with torsion-resistant structure

Abstract

The application discloses a wind power cable with a torsion-resistant structure, which comprises an outer sheath, the outer side of the outer sheath is made of wear-resistant rubber, and the inner side is armored to protect the cable, a plurality of conductive structures are arranged in the inner cavity of the outer sheath, the gap between the outer sheath and the conductive structures is filled with a filler, a torsion-resistant structure is arranged in the outer sheath along the axial direction, and humidity detection structures are equidistantly arranged in the outer sheath from left to right to detect whether the outer sheath is water-permeable. The wind power cable has the advantages that the overall torsion resistance of the cable is improved, the failure problems such as cracking of the outer sheath and wire core wire breakage are delayed, the service life of the cable is effectively prolonged, the replacement frequency of the wind field cable is reduced, the labor and material losses in the operation and maintenance stage are reduced, the overall maintenance cost of the wind power is saved, the water seepage of the cable is visually monitored by means of physical deformation, the water leakage point of the cable can be quickly and directly judged, the insulation failure and the electric leakage safety hazard can be checked in advance, and the electric energy leakage loss caused by the water seepage of the cable is reduced.

Description

Technical Field

[0001] This invention relates to the field of cable technology, specifically to a wind power cable with a torsion-resistant structure. Background Technology

[0002] Wind power generation is a form of clean and renewable energy utilization. Its working principle is as follows: the wind turbine is driven to rotate by the wind, converting the kinetic energy of the wind into the mechanical energy of the turbine shaft. The turbine shaft then drives the generator to operate, ultimately converting the mechanical energy into electrical energy to generate electricity. In the entire wind turbine generator system, cables are the core carriers for power transmission and generator control signal transmission. Whether it is the power transmission cable vertically suspended between the tower and the nacelle, or the pitch control cable between the hub and the nacelle, they must withstand complex alternating operating conditions for a long time.

[0003] Wind conditions are highly variable during wind turbine operation, and the yaw and pitch mechanisms frequently start and stop, causing continuous reciprocating torsional loads on the corresponding cables. Existing conventional wind power cables do not have dedicated torsional reinforcement structures. After being subjected to cyclic torsional shear forces for a long time, the cables are prone to failure problems such as outer sheath cracking and damage, and internal core fatigue and breakage. The overall service life of the cables is significantly shortened, requiring frequent shutdowns to replace cables, which significantly increases the manpower input and material losses in wind farm operation and maintenance, raising the overall maintenance cost.

[0004] Meanwhile, wind power cables are installed in high-altitude, open-air environments for extended periods. Compared to underground power transmission cables, they are subjected to prolonged exposure to ultraviolet radiation, alternating high and low temperatures, and wind and sand erosion, resulting in faster sheath aging. Existing wind power cable structures lack integrated real-time water seepage detection components. When minor damage occurs to the outer sheath, allowing moisture to seep into the cable, maintenance personnel cannot immediately identify potential leaks. Moisture intrusion continuously reduces insulation performance, causing not only power loss but also short circuits and leakage faults, leading to multiple safety risks such as turbine shutdown and electric shock. Summary of the Invention

[0005] The purpose of this invention is to provide a wind power cable with a torsion-resistant structure, so as to at least solve the problems of insufficient torsion resistance and lack of water leakage early warning and monitoring mechanism in the prior art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a wind power cable with a torsion-resistant structure, comprising an outer sheath, the outer side of which is made of wear-resistant rubber and the inner side is armored to protect the cable; the inner cavity of the outer sheath is provided with multiple conductive structures; the gap between the outer sheath and the conductive structures is filled with filler; the torsion-resistant structure is arranged axially inside the outer sheath; and humidity detection structures are equidistantly arranged from left to right inside the outer sheath to detect whether the outer sheath is leaking water. The conductive structure includes an insulating sheath inserted into the inner cavity of the outer sheath, a wire core installed in the inner cavity of the insulating sheath, and an insulating shielding layer composited on the outer wall of the insulating sheath. The insulating shielding layer is made of copper wire braid and prevents the wire core from interfering with external electromagnetic waves.

[0007] It has both insulation and anti-interference functions to achieve stable power transmission.

[0008] Preferably, the core is made of multiple strands of wire twisted together.

[0009] Preferably, the torsion-resistant structure includes a first steel wire and a second steel wire, which are spirally embedded inside the outer sheath and have opposite spiral directions.

[0010] Preferably, the humidity detection structure includes a box body embedded inside an outer sheath. Anti-pull-out rods are evenly arranged from left to right on the top of the front and rear sides of the box body. The anti-pull-out rods are embedded inside the outer sheath to improve the stability between the box body and the outer sheath. Several air holes are evenly opened on the bottom of the box body to allow the box body to communicate with the filler. A water-absorbing resin block is inserted into the bottom of the inner cavity of the box body. An extrusion unit is installed in the middle of the inner cavity of the box body. The top of the left and right inner walls of the box body is provided with a slot and a buffer groove from top to bottom. An ejection unit is installed on the top of the inner wall of the box body and is housed by the buffer groove.

[0011] The water-absorbing resin block converts humidity changes into changes in its own volume, providing power for humidity detection.

[0012] Preferably, the top of the inner wall of the buffer groove is a slope.

[0013] Preferably, the extrusion unit includes a rotating shaft installed in the middle of the inner cavity of the box, two rotating bodies are sleeved on the outer wall of the rotating shaft, and a push plate is installed at the bottom end of the rotating body.

[0014] The rotating body and the push plate work together to form a force-saving lever, ensuring that the ejection unit is driven.

[0015] Preferably, the rotating body is V-shaped, and the push plate extends the power arm for rotating the rotating body.

[0016] Preferably, the ejection unit includes a partition installed on the top of the inner wall of the box, a ejector pin vertically inserted into the center of the partition, the bottom end of the ejector pin contacting the rotating body, and a top plate installed on the top of the ejector pin, the top plate being arc-shaped and inserted into the inner cavity of the buffer groove.

[0017] The deformation of the top plate causes deformation of the outer sheath, which transmits signals for seepage monitoring.

[0018] Preferably, the bottom end of the ejector pin is triangular in shape.

[0019] The wind power cable with a torsion-resistant structure proposed in this invention has the following advantages: 1. This invention sets up a torsion-resistant main structure with a first steel wire and a second steel wire with opposite directions of rotation. When the cable is subjected to torsional load, one of the steel wires tightens with the torsion trend, generating inward radial stress, while the other steel wire expands synchronously, generating outward radial stress. The two radial forces cancel each other out, which can stably maintain the circular cross-section of the cable. At the same time, the transmission conductor is made of multi-strand stranded wire, which can significantly buffer and weaken the transverse shear force acting on the conductor during torsion, improve the conductor's fatigue damage resistance, improve the overall torsion resistance of the cable, delay failure problems such as outer sheath cracking and conductor wire breakage, effectively extend the service life of the cable, reduce the frequency of wind farm cable replacement, reduce manpower and material losses during operation and maintenance, and save the overall maintenance cost of wind power.

[0020] 2. This invention features air vents at the bottom of the housing to connect the interior of the housing with the inner packing of the outer sheath. When the outer sheath is damaged and leaks water, the water-absorbing resin block inside the housing expands upon contact with water. The expansion tension drives the push plate to rotate the rotating body around the axis. The inclined surface of the rotating body presses against the bottom of the ejector pin, converting the horizontal rotational force into a vertical upward thrust. The ejector pin pushes the arc-shaped top plate out of the buffer groove and into the slot to complete positioning. The top plate continuously pushes outward against the outer sheath, causing a slight bulge visible to the naked eye to form on the outer wall of the cable. This invention relies on physical deformation to achieve visual monitoring of cable water leakage, enabling rapid and intuitive identification of cable leakage points, early detection of insulation failure and leakage safety hazards, reduction of power leakage losses caused by cable water leakage, avoidance of unit failures and personal safety accidents caused by leakage and short circuits, and improvement of wind power generation operation safety and power utilization efficiency. Attached Figure Description

[0021] Figure 1 This is a front sectional view of the present invention; Figure 2 For the present invention Figure 1 Enlarged view of point A in the middle; Figure 3 This is a perspective view of the torsion-resistant structure of the present invention; Figure 4 This is a three-dimensional view of the humidity detection structure of the present invention; Figure 5 This is a front cross-sectional view of the humidity detection structure of the present invention; Figure 6 This is a perspective view of the extrusion unit of the present invention; Figure 7 This is a perspective view of the ejector unit of the present invention.

[0022] In the diagram: 1. Outer sheath; 2. Conductive structure; 3. Filler; 4. Torsion-resistant structure; 5. Humidity detection structure; 21. Insulation sheath; 22. Wire core; 23. Insulation shielding layer; 41. First steel wire; 42. Second steel wire; 51. Box body; 52. Pull-out rod; 53. Air hole; 54. Water-absorbing resin block; 55. Extrusion unit; 56. Slot; 57. Buffer groove; 58. Ejection unit; 551. Rotating shaft; 552. Rotating body; 553. Push plate; 581. Partition plate; 582. Ejector pin; 583. Top plate. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Please see Figures 1-7 This invention provides a technical solution: a wind power cable with a torsion-resistant structure, including an outer sheath 1, the outer side of which is made of wear-resistant rubber and the inner side is armored to protect the cable. The inner cavity of the outer sheath 1 is provided with multiple conductive structures 2, the number of which is determined according to the power transmission system. The gap between the outer sheath 1 and the conductive structures 2 is filled with filler 3, which fills the gap to keep the outer sheath 1 in a circular shape. The inner cavity of the outer sheath 1 is provided with a torsion-resistant structure 4 along the axial direction. The inner cavity of the outer sheath 1 is provided with humidity detection structures 5 equidistantly arranged from left to right, which detect whether the outer sheath 1 is leaking water. The conductive structure 2 includes an insulating sheath 21 inserted into the inner cavity of the outer sheath 1. A wire core 22 is installed inside the inner cavity of the insulating sheath 21. The wire core 22 is made of multiple strands of wire twisted together in a regular spiral shape. When the cable twists, the wire core 22 can reduce the shear force caused by the twist by its own shape, thus preventing damage to the wire core 22. An insulating shielding layer 23 is laminated on the outer wall of the insulating sheath 21. The insulating shielding layer 23 is made of copper wire braid. The insulating shielding layer 23 prevents the wire core 22 from interfering with external electromagnetic waves. The braided copper wire is not straight, which can resist the shear force during twisting, has bending resistance, and improves the torsion resistance.

[0025] As a preferred option, the torsion-resistant structure 4 further includes a first steel wire 41 and a second steel wire 42. The first steel wire 41 and the second steel wire 42 are spirally embedded inside the outer sheath 1, and the spiral directions of the two are opposite. If one of the steel wires tightens as the cable twists, the other steel wire will expand. The radial forces of the first steel wire 41 and the second steel wire 42 cancel each other out, thereby improving the overall torsion resistance of the cable.

[0026] By embedding a first steel wire 41 and a second steel wire 42 with opposite directions inside the outer sheath 1 to form a torsion-resistant structure 4, the radial stress caused by torsion can be offset when the cable is subjected to reciprocating torsional loads, maintaining the complete circular cross section of the cable and avoiding damage to the outer sheath 1 caused by long-term torsion. Together with the internal stranded core 22, it can improve the cable's torsion resistance and fatigue resistance, effectively extend the service life of wind power cables, and reduce the frequency of cable replacement and maintenance costs in wind farms.

[0027] As a preferred embodiment, the humidity detection structure 5 further includes a housing 51 embedded inside the outer sheath 1. Anti-pull-out rods 52 are evenly arranged from left to right on the top of the front and rear sides of the housing 51. The anti-pull-out rods 52 are embedded inside the outer sheath 1, improving the stability between the housing 51 and the outer sheath 1. Several air holes 53 are evenly distributed around the bottom of the housing 51, allowing the housing 51 to communicate with the filler. A water-absorbing resin block 54 is inserted into the bottom of the inner cavity of the housing 51. The water-absorbing resin block 54 is sodium polyacrylate, exhibiting a polymer network structure with a high concentration of ions within the resin network. The humidity is much higher than that of the external water body, and a strong osmotic pressure is generated when absorbing water, and the volume gradually increases. The change in humidity is converted into a change in the volume of the water-absorbing resin block 54. An extrusion unit 55 is installed in the middle of the inner cavity of the box body 51. The top of the left and right inner walls of the box body 51 is provided with a slot 56 and a buffer groove 57 from top to bottom. The top of the inner wall of the buffer groove 57 is inclined. The inclined surface can extrude the ejection unit 58, which can protect the elasticity of the ejection unit 58 and promote the movement of the ejection unit 58 during use. The ejection unit 58 is installed on the top of the inner wall of the box body 51 and is stored in the buffer groove 57.

[0028] The humidity detection structure 5 is firmly connected to the outer sheath 1 by using the housing 51 and the anti-pull rod 52. The air hole 53 ensures that water vapor is smoothly conducted to the water-absorbing resin block 54. The water-absorbing resin block 54 made of sodium polyacrylate expands when it comes into contact with water, which converts the water seepage signal into mechanical thrust. The buffer groove 57 and the slot 56 are used to store and position the ejection unit 58. The entire humidity detection structure 5 does not require external power supply and electronic sensing elements. It can realize the autonomous monitoring of cable water seepage by relying on the pure mechanical structure. It can intuitively and quickly identify the water seepage point of the outer sheath 1, and avoid the safety hazards of leakage and short circuit caused by the decline of cable insulation in advance. At the same time, the inclined design of the buffer groove 57 can reduce the stress loss of the ejection unit 58 under normal conditions and improve the long-term service reliability of the humidity detection structure 5.

[0029] As a preferred embodiment, the extrusion unit 55 further includes a rotating shaft 551 installed in the middle of the inner cavity of the box body 51. Two rotating bodies 552 are sleeved on the outer wall of the rotating shaft 551. A push plate 553 is installed at the bottom of the rotating body 552. The rotating body 552 is V-shaped, and the push plate 553 extends the power arm for the rotation of the rotating body 552. This increases the power arm, making it easier for the water-absorbing resin block 54 to push the rotating body 552 with less effort, ensuring that the rotating body 552 can extrude the ejection unit 58 and rise.

[0030] By extending the power arm using the push plate 553 to form a force-saving lever structure, the rotating body 552 can be driven to rotate by the expansion tension of the water-absorbing resin block 54 alone. This reduces the requirements of the entire humidity detection structure 5 on the expansion amount of the water-absorbing resin block 54, ensuring that the extrusion unit 55 can stably and reliably drive the ejection unit 58 upward, improving the trigger sensitivity of the humidity detection structure 5, and avoiding the failure of water seepage monitoring due to insufficient expansion of the water-absorbing resin block 54.

[0031] As a preferred embodiment, the ejector unit 58 further includes a partition 581 installed on the top of the inner wall of the housing 51. A ejector pin 582 is vertically inserted into the center of the partition 581. The bottom end of the ejector pin 582 contacts the rotating body 552. The bottom end of the ejector pin 582 is triangular in shape. As the rotating body 552 rotates, the rotating body 552 changes its direction of movement by squeezing the inclined surface of the ejector pin 582, thereby achieving the purpose of raising the ejector pin 582. A top plate 583 is installed at the top of the ejector pin 582, and the top plate 583 is arc-shaped and inserted into the inner cavity of the buffer groove 57. The top plate 583 is elastic and can gradually bend under the pressure of the ejector pin 582, which can make the top plate 583 lift the outer sheath 1. When the outer sheath 1 undergoes physical change, it serves as a water leakage signal.

[0032] The partition 581 limits the position of the ejector pin 582. The ejector pin 582 with its triangular inclined surface works in conjunction with the rotating body 552 to achieve the direction and transmission of force. The arc-shaped elastic top plate 583 then converts the pushing force into a visible bulge deformation on the outside of the outer sheath 1. This can transform the cable water leakage signal into an intuitive change in appearance, making it easy for maintenance personnel to quickly locate the point of water leakage in the outer sheath 1 and promptly investigate potential safety hazards such as leakage and short circuit. At the same time, under normal conditions, the top plate 583 is stored inside the buffer groove 57, which will not damage the original complete and round structure of the outer sheath 1, ensuring the overall structural stability under cable laying and torsion conditions.

[0033] Its detailed connection method is a well-known technology in this field. The following mainly introduces the working principle and process, and the specific work is as follows.

[0034] Step 1: Using the wire core 22 as the power transmission conductor, wind power is transmitted. During the power transmission process, the insulation sheath 21 insulates the wire core 22 to prevent leakage. The insulation shielding layer 23 has conductivity and shields electromagnetic waves and other signal interference. The filling material 3 keeps the outer sheath 1 round and separates the wire core 22 to achieve stable power transmission. Step two: Once the cable twists, the first steel wire 41 and the second steel wire 42 have opposite spiral directions. If the first steel wire 41 tightens in the direction of twisting, the second steel wire 42 expands in the direction of twisting. The radial forces generated by the first steel wire 41 and the second steel wire 42 are similar in magnitude and opposite in direction, thus canceling each other out. The circular structure of the cable is maintained. Moreover, the core 22 is made of multiple strands of wire twisted together in a spiral structure, which can reduce the shear force caused by twisting, improve the overall torsional resistance of the cable, and extend its service life. Step 3: With the wind and sun and the changing seasons, the outer sheath 1 will gradually age. If the outer sheath 1 cracks, the inside of the outer sheath 1 will be connected to the atmosphere, causing moisture or water in the air to enter. The water-absorbing resin block 54 absorbs the moisture. The water-absorbing resin block 54 is a three-dimensional cross-linked polymer network structure. The ion concentration in the resin network is much higher than that of the external water body. Ionization generates strong osmotic pressure. External water molecules are continuously absorbed into the network structure, and the volume gradually increases, converting the humidity change into a volume change of the water-absorbing resin block 54. Step four: The expansion force of the water-absorbing resin block 54 pushes the push plate 553, causing the two rotating bodies 552 to rotate inward simultaneously. Since the power arm is longer than the resistance arm, the rotating body 552 exerts a strong force on the inclined surface of the ejector pin 582, ensuring that the ejector pin 582 moves upward and drags the top plate 583. The top plate 583 gradually slides out of the buffer groove 57. After the end of the top plate 583 enters the slot 56, the top plate 583 is positioned. The top plate 583 continues to press the outer sheath 1. From the outside, the outer sheath 1 shows a bulge. The deformation of the outer sheath 1 indicates that the outer sheath 1 is damaged.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wind power cable with a torsion-resistant structure, comprising an outer sheath (1), wherein the outer side of the outer sheath (1) is made of wear-resistant rubber and the inner side is armored to protect the cable, characterized in that, The outer sheath (1) has multiple conductive structures (2) inside its cavity. The gap between the outer sheath (1) and the conductive structures (2) is filled with filler (3). The outer sheath (1) has a torsion-resistant structure (4) arranged along the axial direction inside its interior. The outer sheath (1) has humidity detection structures (5) arranged equidistantly from left to right inside its interior. The humidity detection structures (5) are used to detect whether the outer sheath (1) leaks water. The conductive structure (2) includes an insulating skin (21) inserted into the inner cavity of the outer sheath (1). A wire core (22) is installed in the inner cavity of the insulating skin (21). An insulating shielding layer (23) is laminated on the outer wall of the insulating skin (21). The insulating shielding layer (23) is made of copper wire braiding. The insulating shielding layer (23) prevents the wire core (22) from interfering with external electromagnetic waves.

2. A wind power cable with a torsion-resistant structure according to claim 1, characterized in that, The core (22) is made of multiple strands of wire twisted together.

3. A wind power cable with a torsion-resistant structure according to claim 2, characterized in that, The torsion-resistant structure (4) includes a first steel wire (41) and a second steel wire (42). The first steel wire (41) and the second steel wire (42) are spirally embedded inside the outer sheath (1), and the spiral directions of the two are opposite.

4. A wind power cable with a torsion-resistant structure according to claim 3, characterized in that, The humidity detection structure (5) includes a box (51) embedded inside the outer sheath (1). Anti-pull rods (52) are evenly arranged on the top of the front and rear sides of the box (51) from left to right. The anti-pull rods (52) are embedded inside the outer sheath (1) to improve the stability between the box (51) and the outer sheath (1). Several air holes (53) are evenly opened on the bottom of the box (51) around the perimeter. The air holes (53) allow the box (51) to communicate with the filler. A water-absorbing resin block (54) is inserted into the bottom of the inner cavity of the box (51). A squeezing unit (55) is installed in the middle of the inner cavity of the box (51). A slot (56) and a buffer groove (57) are opened on the top of the left and right inner walls of the box (51) from top to bottom. An ejection unit (58) is installed on the top of the inner wall of the box (51). The ejection unit (58) is housed by the buffer groove (57).

5. A wind power cable with a torsion-resistant structure according to claim 4, characterized in that, The top of the inner wall of the buffer groove (57) is sloping.

6. A wind power cable with a torsion-resistant structure according to claim 5, characterized in that, The extrusion unit (55) includes a rotating shaft (551) installed in the middle of the inner cavity of the box body (51). Two rotating bodies (552) are sleeved on the outer wall of the rotating shaft (551), and a push plate (553) is installed at the bottom of the rotating body (552).

7. A wind power cable with a torsion-resistant structure according to claim 6, characterized in that, The rotating body (552) is V-shaped, and the push plate (553) extends the power arm for the rotation of the rotating body (552).

8. A wind power cable with a torsion-resistant structure according to claim 7, characterized in that, The ejection unit (58) includes a partition (581) installed on the top of the inner wall of the box (51). A ejector pin (582) is vertically inserted into the center of the partition (581). The bottom end of the ejector pin (582) is in contact with the rotating body (552). A top plate (583) is installed on the top of the ejector pin (582), and the top plate (583) is inserted into the inner cavity of the buffer groove (57) in an arc shape.

9. A wind power cable with a torsion-resistant structure according to claim 8, characterized in that, The bottom of the pin (582) is triangular.

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