Aluminum alloy core crosslinked polyethylene photovoltaic cable and spiral skeleton forming apparatus thereof

Abstract

The application discloses an aluminum alloy core crosslinked polyethylene photovoltaic cable and a spiral framework forming equipment thereof, and belongs to the technical field of wire and cable manufacturing. The cable comprises an aluminum alloy conductor, an inner semiconductive shielding layer wrapped outside the aluminum alloy conductor, a spiral support sheath wrapped outside the inner semiconductive shielding layer, an outer semiconductive shielding layer wrapped outside the spiral support sheath, and an outer sheath wrapped outside the outer semiconductive shielding layer. The spiral support sheath is spirally wrapped on the outer surface of the inner semiconductive shielding layer by using prefabricated foamed crosslinked polyethylene strips, and the foamed crosslinked polyethylene strips have uniformly distributed closed cell microcellular structures. The closed cell microcellular structures of the foamed crosslinked polyethylene strips are combined with the macroscopic geometric shape of the spiral wrapping by arranging the spiral support sheath, so that the single structural layer has four functions of insulation, buffering, support and anti-biting.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, specifically to an aluminum alloy core cross-linked polyethylene photovoltaic cable and its spiral skeleton forming equipment. Background Technology

[0002] Photovoltaic power generation systems, as a clean energy technology, are widely used globally. The environments in which photovoltaic power plants are installed are becoming increasingly diverse, including harsh environments such as high-altitude areas, deserts, Gobi, and mountains. In these environments, photovoltaic cables face multiple severe challenges:

[0003] First, there are the electrical performance challenges at high altitudes. In high-altitude areas, the air is thinner, the air pressure is lower, and the insulating strength of the air decreases, making cables more susceptible to corona discharge. Corona discharge not only causes energy loss but also produces ozone and nitrogen oxides, accelerating the aging of cable insulation materials and potentially leading to cable breakdown in severe cases. Based on the general rule that air insulation strength decreases by approximately 8%-10% for every 1000 meters increase in altitude, the corona initiation voltage of cables decreases significantly at altitudes above 3000 meters, placing even higher demands on cable insulation performance.

[0004] Second, there is the thermomechanical stress caused by drastic temperature differences. Photovoltaic power plants are often located in areas with large diurnal temperature variations, especially in high-altitude desert regions where these variations can reach 30°C-50°C. During repeated thermal expansion and contraction, the cable material experiences shear stress due to differences in the coefficients of thermal expansion between different material layers. Over the long term, this can lead to interlayer separation and interface cracking, reducing the cable's structural integrity and electrical performance.

[0005] Third, mechanical damage caused by animal gnawing. Outdoor photovoltaic power stations are frequently threatened by rodents. Animal gnawing can directly damage the cable sheath, exposing the conductor and causing short circuits. Traditional solutions mainly rely on adding chemical rodent repellents, such as capsaicin and bittering agents, to the sheath material. However, chemical rodent repellents have the following problems: first, they are not environmentally friendly and may harm the environment and animals; second, their effectiveness diminishes over time, as the rodent repellent gradually leaches out or becomes ineffective; and third, they cannot address all types of animal gnawing.

[0006] Fourth, mechanical damage during installation and laying. Photovoltaic cables may be subjected to mechanical forces such as tension, bending, compression, and impact during installation. In particular, when the cable is laid on gravel ground or in conduit, the sheath is prone to scratches, indentations, and other damage, which can affect its long-term service life.

[0007] Therefore, there is an urgent need to develop a new type of photovoltaic cable that can achieve a balance between high-altitude adaptability, resistance to mechanical damage, and long-term reliability in harsh environments, while also taking into account production efficiency and cost control. Summary of the Invention

[0008] To achieve the above objectives, the present invention provides the following technical solution: an aluminum alloy core cross-linked polyethylene photovoltaic cable, comprising: an aluminum alloy conductor;

[0009] An inner semiconductive shielding layer covering the aluminum alloy conductor;

[0010] A spiral support sleeve covering the inner semiconductive shielding layer;

[0011] An outer semi-conductive shielding layer covering the spiral support sheath;

[0012] And an outer sheath covering the outer semiconductive shielding layer;

[0013] The spiral support sleeve is formed by wrapping a pre-formed foamed cross-linked polyethylene tape around the outer surface of the inner semi-conductive shielding layer in a spiral shape. The foamed cross-linked polyethylene tape has a uniformly distributed closed-cell microporous structure inside, and the material of the tape has a three-dimensional network molecular structure after cross-linking treatment.

[0014] The foamed cross-linked polyethylene tape has a flat strip cross-section, with its width direction parallel to the cable axis and its thickness direction being the radial direction of the cable; the tape is a straight, flat strip before wrapping, and forms a continuous helical spring geometry after wrapping.

[0015] Preferably, the adjacent spiral coils of the spiral support sheath are fused and bonded at the contact point through the relative surfaces of the foamed cross-linked polyethylene tape to form a continuous integrated spiral tubular structure.

[0016] Preferably, the spiral support sheath has 1-2 wrapping layers, a wrapping angle of 45°-60°, a continuous spiral gap between adjacent spiral coils, a spiral gap width G of 0.5-1.5mm, and a spiral pitch P to spiral height H ratio of 2-4.

[0017] A spiral skeleton forming device for manufacturing aluminum alloy core cross-linked polyethylene photovoltaic cables includes a base, the surface of which is sequentially provided with the following features along the cable travel direction:

[0018] A strip supply device, installed on a rotating wrapping head, is used to release pre-formed foamed cross-linked polyethylene strip;

[0019] The rotating wrapping head can rotate around the cable axis and is used to wrap the strip around the outer surface of the cable core in a spiral shape, forming a spiral structure in which adjacent spiral coils contact each other;

[0020] A heating and welding device is installed after the rotating wrapping head to heat the wrapped strip so that the contact points of adjacent spiral coils melt and bond together.

[0021] A cooling and shaping device is installed after the heating and welding device to quickly cool and shape the heated spiral structure.

[0022] A linkage mechanism is also provided between the rotating wrapping head and the heating welding device. The linkage mechanism is also connected to a strip supply and replacement device. When the rotating wrapping head wraps, the linkage mechanism drives the strip supply and replacement device to rotate.

[0023] Preferably, the rotating wrapping head includes a frame with a central hole, a turntable connected to one side of the frame via a hollow shaft, a strip feeding device mounted on the outer surface of the turntable via an angle-adjustable bracket, a gear assembly mounted on the outer surface of the hollow shaft, the gear assembly driving the turntable to rotate via a drive motor, and a side plate mounted on one side of the frame, the side plate being connected to a strip feeding replacement device via a shaft.

[0024] The strip supply device and the strip supply replacement device have the same structure. A quick-release structure is provided between the strip supply device and the angle adjustable bracket, and between the strip supply replacement device and the rotating shaft.

[0025] The installation angle of the strip supply device is adjustable, with an adjustment range of 45°-60°.

[0026] Preferably, a pressure roller mechanism is further provided between the rotating wrapping head and the heating and welding device. The pressure roller mechanism includes a support, and a second turntable is provided on the surface of the support. Adjustable pressure rollers are respectively installed on both sides of the second turntable for pressing the spirally wound strip.

[0027] The heating and welding device includes a second support, on the surface of which a third turntable is provided. Infrared heating rods and conductive slip rings are symmetrically mounted on the outer surface of the third turntable, and the infrared heating rods are electrically connected to the conductive slip rings.

[0028] Preferably, the linkage mechanism includes a linkage rod installed between the second support and the frame, and three transmission gears are connected to the outer surface of the linkage rod. The three transmission gears are respectively engaged with toothed rings provided on the outer surfaces of the turntable, the second turntable and the third turntable.

[0029] A rotating gear is mounted on the surface of the rotating shaft connected to the strip supply and replacement device, and the rotating gear meshes with the gear ring on the surface of the turntable.

[0030] Preferably, the transmission ratio between the toothed ring on the turntable surface and the rotating gear is set to a transmission ratio that keeps the rotation of the strip supply replacement device and the revolution of the turntable fixed.

[0031] Preferably, the heating and welding device includes an infrared heating lamp installed on the third turntable. When the infrared heating lamp radiates heat to the wrapped strip, the contact point of the adjacent spiral rings forms a heat accumulation effect due to the heat being trapped between the two strips. The temperature is higher than the outer surface temperature of the strip, and a natural temperature difference is formed between the contact point and the outer surface, thereby achieving selective welding with preferential melting and bonding at the contact point.

[0032] Preferably, the heating welding device further includes:

[0033] An infrared temperature sensor is installed on the third turntable and rotates synchronously with the infrared heating lamp to monitor the surface temperature of the strip in the heating zone in real time.

[0034] A PID temperature controller, connected to the infrared temperature sensor, adjusts the heating power of the infrared heating lamps based on temperature feedback to stabilize the surface temperature of the strip within a set range of 80-120℃.

[0035] This invention provides an aluminum alloy core cross-linked polyethylene photovoltaic cable and its spiral skeleton forming equipment. It has the following beneficial effects:

[0036] 1. This invention combines the closed-cell microporous structure of foamed cross-linked polyethylene tape with the macroscopic geometry of spiral wrapping through a spiral support sleeve, enabling a single structural layer to simultaneously possess four major functions: insulation, cushioning, support, and anti-biting. Specifically, the foamed micropores form microscopic air pocket units providing cushioning and gas-solid composite insulation; the spiral structure creates a macroscopic spring effect to absorb impact energy; the spiral protrusions form annular reinforcing ribs to disperse the conductor weight; and the textured surface of the spiral forms a physical labyrinth barrier for physical repellency. This effectively solves the problems of bulky traditional multi-layer structures and the environmentally unfriendly and short-lasting effects of chemical rodent repellents.

[0037] 2. By mounting the strip supply device on a rotating disc and rotating synchronously with it, and by using a mechanical linkage mechanism consisting of a linkage rod, transmission gear, and gear ring to ensure synchronous rotation of the rotating disc, the second rotating disc, the third rotating disc, and the strip supply replacement device, the entire path of the strip from the disc to the guide pulley is free of relative motion. This completely solves the problem of strip winding and knotting caused by repeated twisting in traditional fixed strip supply structures, ensuring the stability of the wrapping process. At the same time, the quick-release structure allows for rapid switching of the strip supply device, improving production efficiency.

[0038] 3. By installing infrared heating lamps on the third turntable and rotating synchronously with the wrapping head, 360° uniform heating is achieved. The heating temperature is controlled at 80-120℃. Utilizing the heat accumulation effect at the contact points, heat is trapped between the two strips at the contact points of adjacent spiral coils, resulting in heat accumulation. The temperature is naturally 20-60℃ higher than the outer surface temperature. This achieves selective welding, where the contact points preferentially melt and bond, while the outer surface only slightly softens, and the internal foamed microporous structure remains intact. This solves the technical contradiction of needing to both bond firmly and protect the microporous structure during foamed material welding. At the same time, the combination of infrared temperature sensors and PID temperature controllers overcomes environmental interference and ensures the stability of the welding quality. Attached Figure Description

[0039] Figure 1 This is a perspective view of the spiral support sheath in an aluminum alloy core cross-linked polyethylene photovoltaic cable according to the present invention;

[0040] Figure 2 This is a cross-sectional view of the aluminum alloy core cross-linked polyethylene photovoltaic cable of the present invention;

[0041] Figure 3 This is a first-view perspective perspective view of the aluminum alloy core cross-linked polyethylene photovoltaic cable spiral skeleton forming equipment of the present invention;

[0042] Figure 4 This is a second-view perspective perspective view of the aluminum alloy core cross-linked polyethylene photovoltaic cable and its spiral skeleton forming equipment according to the present invention;

[0043] Figure 5 This is a third-view perspective view of the aluminum alloy core cross-linked polyethylene photovoltaic cable and its spiral skeleton forming equipment in this invention.

[0044] Figure 6 In this invention Figure 3 Enlarged view of point A.

[0045] The components include: 1. Aluminum alloy conductor; 2. Inner semi-conductive shielding layer; 3. Spiral support sleeve; 4. Outer semi-conductive shielding layer; 5. Outer sleeve; 6. Base; 7. Strip feeding device; 8. Rotary wrapping head; 81. Frame; 82. Hollow rotating shaft; 83. Turntable; 84. Gear assembly; 85. Drive motor; 86. Side plate; 9. Heating and welding device; 91. Support two; 92. Third turntable; 93. Infrared heating rod; 94. Conductive slip ring; 95. Infrared temperature sensor; 10. Cooling and shaping device; 11. Linkage mechanism; 111. Linkage rod; 112. Transmission gear; 113. Gear ring; 114. Rotating gear; 12. Strip feeding and replacement device; 13. Pressure roller mechanism; 131. Support; 132. Second turntable; 133. Pressure roller; 14. Large feeding rack. Detailed Implementation

[0046] 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, other embodiments obtained by those skilled in the art without creative effort are all within the scope of protection of the present invention.

[0047] refer to Figures 1-6 :

[0048] Example 1

[0049] This embodiment provides an aluminum alloy core cross-linked polyethylene photovoltaic cable, which is suitable for harsh environments with high altitude, strong ultraviolet radiation, large temperature differences, and high risk of animal gnawing.

[0050] like Figure 1 As shown, the photovoltaic cable includes, from the inside out, an aluminum alloy conductor 1, an inner semi-conductive shielding layer 2, a spiral support sheath 3, an outer semi-conductive shielding layer 4, and an outer sheath 5.

[0051] The aluminum alloy conductor 1 is made of stranded 8030 series aluminum alloy monofilaments. In this embodiment, the diameter of the aluminum alloy monofilament is 1.5 mm, and the stranding pitch ratio is 12. This aluminum alloy material has excellent electrical conductivity and creep resistance, while being about 30% lighter than pure copper conductors, making it easier to install and lay.

[0052] An inner semiconductive shielding layer 2, with a thickness of 0.4 mm, covers the outer surface of the aluminum alloy conductor 1 and is formed by extrusion of a cross-linkable semiconductor shielding material. The function of the inner semiconductive shielding layer 2 is to uniformly distribute the electric field on the conductor surface and prevent partial discharge.

[0053] The spiral support sleeve 3 is the core innovation of this invention. This sleeve is made of pre-formed foamed cross-linked polyethylene tape, spirally wrapped around the outer surface of the inner semi-conductive shielding layer 2. The foamed cross-linked polyethylene tape has a uniformly distributed closed-cell microporous structure, a foaming degree of 40%, a tape thickness of 1.0 mm, and a tape width of 20 mm. The tape undergoes irradiation cross-linking treatment, achieving a cross-linking degree of 65%, with the molecular chains forming a three-dimensional network structure, endowing the material with elastic memory and resistance to permanent deformation.

[0054] like Figure 1 As shown, the foamed cross-linked polyethylene tape has a flat, strip-shaped cross-section, with its width direction parallel to the cable axis and its thickness direction in the radial direction of the cable. Before wrapping, the tape is a straight, flat strip; after wrapping, it forms a continuous helical spring geometry.

[0055] In this embodiment, the spiral support sleeve 3 has one wrapping layer, a wrapping angle of 52°, a continuous spiral gap between adjacent spiral coils, a spiral gap width G of 1.0 mm, and a spiral pitch P to spiral height H ratio of 3.

[0056] like Figure 1 and Figure 2 As shown, adjacent spiral coils of the spiral support sleeve 3 are fused together at the contact point by the opposing surfaces of the foamed cross-linked polyethylene tape, forming a continuous, integrated spiral tubular structure. This fusion bonding is achieved in a subsequent heating and welding process, the specific process of which will be described in detail in the equipment embodiments.

[0057] The outer semiconductive shielding layer 4 covers the outer surface of the spiral support sheath 3, with a thickness of 0.4 mm, and is extruded from the same material as the inner semiconductive shielding layer 2. The function of the outer semiconductive shielding layer 4 is to confine the electric field inside the cable and to act as an equipotential layer.

[0058] The outer sheath 5 covers the outer surface of the outer semiconductive shielding layer 4, with a thickness of 1.5 mm, and is extruded from weather-resistant cross-linked polyethylene material. The outer sheath 5 has good resistance to ultraviolet aging and environmental stress cracking, protecting the internal structure from the influence of the external environment.

[0059] The photovoltaic cable of this embodiment combines the closed-cell microporous structure of the foamed cross-linked polyethylene tape with the macroscopic geometry of the spiral wrapping through the spiral support sheath 3, enabling a single structural layer to simultaneously possess four major functions: insulation, buffering, support, and anti-biting. Specifically, the foamed micropores form countless micro-airbag units, generating microscopic compression to absorb energy upon radial impact; the spiral structure creates a macroscopic spring effect, generating elastic deformation to absorb energy upon radial impact; the spiral protrusions form annular reinforcing ribs, evenly distributing the conductor weight to avoid localized pressure; and the uneven texture on the spiral surface forms a physical labyrinth barrier, preventing animals from applying force and generating a counterforce when biting, achieving physical repellency rather than chemical repellency, with no environmental issues and long-lasting effects.

[0060] Example 2:

[0061] This embodiment provides a spiral skeleton forming device for manufacturing the aluminum alloy core cross-linked polyethylene photovoltaic cable described in Embodiment 1.

[0062] The equipment includes a base 6, on the surface of which, along the cable travel direction, are sequentially arranged: a strip feeding device 7, a rotating wrapping head 8, a heating and welding device 9, and a cooling and shaping device 10. The entire equipment adopts a modular design, and the various devices are mechanically synchronized through a linkage mechanism 11, ensuring coordinated operation of the rotating components without the need for a complex electrical control system.

[0063] A strip supply device 7 is mounted on a rotary wrapping head 8 for releasing pre-formed foamed cross-linked polyethylene strip. The rotary wrapping head 8 includes a frame 81 with a central hole, and a turntable 83 is connected to one side of the frame 81 via a hollow shaft 82. The strip supply device 7 is mounted on the outer surface of the turntable 83 via an angle-adjustable bracket. This design allows the strip supply device 7 to rotate with the turntable 83. A gear assembly 84 is mounted on the outer surface of the hollow shaft 82, and the gear assembly 84 drives the turntable 83 to rotate via a drive motor 85. The drive motor 85 is a servo motor, which can be precisely linked with the traction speed to ensure the accuracy of the wrapping pitch.

[0064] To address the issue of production efficiency disruption caused by downtime for strip replacement, this embodiment includes a side plate 86 mounted on one side of the frame 81. The side plate 86 is connected to the strip supply replacement device 12 via a pivot. The strip supply replacement device 12 has the same structure as the strip supply device 7, and both are equipped with quick-release mechanisms between themselves and their respective mounting brackets. These quick-release mechanisms can be spring-loaded or press-type quick-release components, including mounting holes, positioning slots, semi-circular plates, moving plates, pressing plates, and springs. Pressing the two pressing plates separates the semi-circular plate from the positioning slot, allowing it to be pulled out for replacement.

[0065] The ingenuity of this design lies in the fact that when the strip supply device 7 is about to run out of strip, the operator can pre-install a new roll of strip onto the strip supply replacement device 12. Driven by the linkage mechanism 11, the strip supply replacement device 12 continuously rotates during equipment operation, always remaining in a standby state. When changing strips, only a brief stop is needed; the quick-release structure allows the strip supply replacement device 12 to be quickly switched to the working position, thus resuming production and significantly reducing downtime.

[0066] The installation angle of the tape supply device 7 is adjustable, with an adjustment range of 45°-60°. This design corresponds to the wrapping angle requirements of the spiral skeleton sheath. By adjusting the installation angle of the tape supply device 7, the angle at which the tape wraps to the cable surface can be precisely controlled, thereby changing the spiral pitch and spiral gap width to adapt to the production needs of cables of different specifications.

[0067] A pressure roller mechanism 13 is also provided between the rotating wrapping head 8 and the heating and welding device 9. The pressure roller mechanism 13 includes a bracket 131, and a second turntable 132 is provided on the surface of the bracket 131. Pressure rollers 133 with adjustable distance are respectively installed on both sides of the second turntable 132. After the strip is just wrapped around the cable surface, pressure is immediately applied by the pressure rollers 133 to ensure that the strip is tightly attached to the inner semi-conductive shielding layer, expel any air that may be present, and create good conditions for subsequent heating and welding. The distance between the pressure rollers 133 can be adjusted to accommodate cables of different diameters and strips of different thicknesses. The heating and welding device 9 is one of the core innovations of this invention. The heating and welding device 9 includes a second bracket 91, and a third turntable 92 is provided on the surface of the second bracket 91. Infrared heating rods 93 and conductive slip rings 94 are symmetrically installed on the outer surface of the third turntable 92. The infrared heating rods 93 and conductive slip rings 94 are electrically connected. Unlike traditional fixed annular heating tubes, this embodiment mounts infrared heating rods 93 on a third turntable 92, rotating synchronously with it. This achieves 360° uniform heating. As the turntable rotates, the infrared heating rods 93 provide uniform radiation around the cable's circumference without any blind spots, eliminating the shadowing effect and uneven circumferential temperature problems associated with fixed heating. The symmetrically mounted infrared heating rods 93 ensure that each welding point is irradiated multiple times within one revolution during rotation, resulting in more uniform heat accumulation. When the infrared heating lamps 91 provide comprehensive radiant heating to the wrapped strip, the contact points of adjacent spiral coils accumulate heat between the two strips, creating a heat accumulation effect. The temperature at these points is naturally higher than the outer surface temperature of the strip, forming a natural temperature difference between the contact points and the outer surface, enabling selective welding with preferential melting and bonding at the contact points. The physical mechanism of this effect is as follows: when the outer surface of the strip is exposed to air, heat is rapidly dissipated through convection, keeping the temperature at a low level; however, at the contact point of adjacent spiral coils, heat is trapped between the two strips and cannot dissipate effectively, leading to heat accumulation and a natural temperature increase. This natural temperature difference causes the contact point to preferentially reach the welding temperature while the outer surface only slightly softens, achieving selective welding. In this embodiment, the natural temperature difference between the contact point and the outer surface is controlled between 20-60°C, ensuring that when the contact point temperature reaches the welding temperature of 80-120°C, the outer surface temperature remains below 80°C, thus guaranteeing the integrity of the internal foamed microporous structure.

[0068] To further ensure the stability of welding quality, the heating welding device 9 also includes an infrared temperature sensor 95 and a PID temperature controller. A protective cover is fitted over the outer surface of the infrared heating lamp 91, and the infrared temperature sensor 95 is mounted on the inner wall of the protective cover, rotating synchronously with the infrared heating lamp 91 to monitor the surface temperature of the strip in the heating zone in real time. This rotating temperature measurement design ensures the accuracy and real-time nature of temperature detection, avoiding measurement errors caused by angle changes in fixed temperature sensors.

[0069] The PID temperature controller is connected to the infrared temperature sensor 95 and adjusts the heating power of the infrared heating lamp 91 based on temperature feedback. When the detected temperature is lower than the set value, the PID controller increases the heating power; when the detected temperature is higher than the set value, the PID controller decreases the heating power; when the detected temperature equals the set value, the PID controller maintains the current power. A proportional-integral-derivative algorithm is used to eliminate steady-state errors and prevent temperature overshoot, stabilizing the strip surface temperature within the set range of 80-120℃ with an accuracy of ±2℃.

[0070] This closed-loop temperature control system effectively overcomes the impact of interference factors such as changes in ambient temperature, fluctuations in linear velocity, and aging of infrared heating tubes on the heating effect, ensuring the stability and consistency of long-term production.

[0071] The linkage mechanism 11 includes a linkage rod 111 installed between the support 91 and the frame 81. Three transmission gears 112 are connected to the outer surface of the linkage rod 111. The three transmission gears 112 mesh with gear rings 113 on the outer surfaces of the turntable 83, the second turntable 132, and the third turntable 92, respectively. Through the linkage rod 111 and the three transmission gears 112, the three rotating components—turntable 83 (for wrapping), the second turntable 132 (for pressing), and the third turntable 92 (for heating)—are synchronously connected. When the drive motor 85 drives the turntable 83 to rotate, the gear rings 113 on the surface of the turntable 83 drive the meshing transmission gears 112 to rotate. The transmission gears 112 transmit power to the other two transmission gears 112 through the linkage rod 111, thereby driving the second turntable 132 and the third turntable 92 to rotate synchronously. This purely mechanical synchronous transmission scheme ensures that the rotational speeds of the three turntables are completely consistent without the need for a complex electrical control system, ensuring the coordinated operation of the wrapping, pressing, and heating processes. Meanwhile, mechanical transmission has the advantages of fast response, no delay, and high reliability, making it particularly suitable for high-speed continuous production.

[0072] A rotating gear 114 is mounted on the surface of the shaft connected to the strip supply and replacement device 12. The rotating gear 114 meshes with a gear ring 113 on the surface of the turntable 83. The transmission ratio between the gear ring 113 and the rotating gear 114 on the surface of the turntable 83 is set to maintain a fixed transmission ratio between the rotation of the strip supply and replacement device 12 and the revolution of the turntable 83. This ensures that the strip supply and replacement device 12 always maintains the same motion state as the strip supply device 7 in the standby state. When the strip on the strip supply device 7 is depleted and needs to be switched, the strip supply and replacement device 12 is already in a synchronous rotation state and can be directly switched without additional starting and synchronization processes, achieving rapid strip change.

[0073] A cooling and shaping device 10 is installed after the heating and welding device 9 to rapidly cool and shape the heated spiral structure. In this embodiment, the cooling and shaping device 10 is an annular air-cooling device, including an annular air-cooling hood, a refrigeration unit, and a temperature controller. The annular air-cooling hood is fitted around the cable to form an annular cooling air duct. The refrigeration unit is connected to the annular air-cooling hood to cool the cooling gas to a set temperature. The temperature controller controls the outlet air temperature to be stable at 18°C. The cooling zone of the cooling and shaping device is 500mm long, and the cooling rate is controlled at 80°C / s. After the heated strip leaves the heating zone, it is immediately forced to cool, rapidly reducing the temperature below the strip's softening point, locking the molecular chain entanglement state at the welding interface, and preventing a decrease in welding strength or deformation due to slow cooling. At the same time, rapid cooling causes the spiral structure to tightly hug the outer surface of the cable core due to thermal shrinkage, enhancing the bonding force between the spiral skeleton and the cable.

[0074] The working process of the device in this embodiment is as follows:

[0075] The first step is to install the pre-formed foamed cross-linked polyethylene tape onto the tape supply device 7, and at the same time install the spare tape roll onto the tape supply replacement device 12.

[0076] The second step is to start the drive motor 85, which drives the turntable 83 to rotate. The turntable 83 drives the second turntable 132, the third turntable 92 and the strip supply and replacement device 12 to rotate synchronously through the linkage mechanism 11.

[0077] Third, the cable core is pulled through the equipment at a constant speed. The strip feeding device 7 on the turntable 83 revolves with the turntable, wrapping the strip around the surface of the cable core at a set angle to form a spiral structure in which adjacent spiral coils contact each other.

[0078] The fourth step is that the wrapped cable enters the pressure roller mechanism 13, and the pressure roller 133 presses the strip tightly against the surface of the cable core.

[0079] Fifth, the cable enters the heating and welding device 9. Infrared heating lamps 91 on the third turntable 92 rotate with the turntable, providing uniform 360° radiant heating to the cable. During heating, the contact points of adjacent spiral coils reach higher temperatures than the outer surface due to heat accumulation, achieving selective welding. Infrared temperature sensors 95 monitor the temperature in real time, and a PID controller adjusts the heating power to stabilize the temperature at 100±2℃.

[0080] The sixth step involves heating and welding the cable, which then enters the cooling and shaping device 10 for rapid cooling and shaping, thus completing the formation of the spiral skeleton.

[0081] When the strip on the strip supply device 7 is exhausted, stop the machine briefly, and then switch the strip supply replacement device 12 to the working position through the quick-release structure to continue production.

[0082] 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 variations 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 cross-linked polyethylene photovoltaic cable with an aluminum alloy core, characterized in that, include: Aluminum alloy conductor (1); An inner semiconductive shielding layer (2) covering the aluminum alloy conductor; A spiral support sleeve (3) covering the inner semiconductive shielding layer; An outer semiconductive shielding layer (4) covering the spiral support sheath; And an outer sheath (5) covering the outer semiconductive shielding layer; The spiral support sleeve (3) is formed by wrapping a pre-formed foamed cross-linked polyethylene tape around the outer surface of the inner semiconductive shielding layer (2) in a spiral shape. The foamed cross-linked polyethylene tape has a uniformly distributed closed-cell microporous structure inside, and the material of the tape has a three-dimensional network molecular structure after cross-linking treatment. The foamed cross-linked polyethylene tape has a flat strip cross-section, with its width direction parallel to the cable axis and its thickness direction being the radial direction of the cable; the tape is a straight, flat strip before wrapping, and forms a continuous helical spring geometry after wrapping.

2. The aluminum alloy core cross-linked polyethylene photovoltaic cable according to claim 1, characterized in that, The adjacent spiral rings of the spiral support sleeve (3) are fused and bonded at the contact point through the relative surfaces of the foamed cross-linked polyethylene tape to form a continuous integrated spiral tubular structure.

3. The aluminum alloy core cross-linked polyethylene photovoltaic cable according to claim 1, characterized in that, The spiral support sleeve (3) has 1-2 wrapping layers, a wrapping angle of 45°-60°, and a continuous spiral gap between adjacent spiral rings. The width G of the spiral gap is 0.5-1.5mm, and the ratio of the spiral pitch P to the spiral height H is 2-4.

4. A spiral skeleton forming device for manufacturing the aluminum alloy core cross-linked polyethylene photovoltaic cable according to any one of claims 1-3, characterized in that, Including a base (6), the surface of the base (6) is provided with the following sequentially along the cable travel direction: A strip supply device (7) is installed on a rotating wrapping head (8) for releasing pre-formed foamed cross-linked polyethylene strip; The rotating wrapping head (8) can rotate around the cable axis and is used to wrap the strip around the outer surface of the cable core in a spiral shape to form a spiral structure in which adjacent spiral rings contact each other; A heating and welding device (9) is installed after the rotating wrapping head (8) to heat the wrapped strip so that the contact points of adjacent spiral rings melt and bond together. A cooling and shaping device (10) is installed after the heating and welding device (9) and is used to quickly cool and shape the heated spiral structure. A linkage mechanism (11) is also provided between the rotating wrapping head (8) and the heating welding device (9). The linkage mechanism (11) is also connected to the strip supply and replacement device (12). When the rotating wrapping head (8) wraps, the linkage mechanism (11) drives the strip supply and replacement device (12) to rotate.

5. The spiral skeleton forming equipment for aluminum alloy core cross-linked polyethylene photovoltaic cables according to claim 4, characterized in that, The rotating wrapping head (8) includes a frame (81) with a central hole. A turntable (83) is connected to one side of the frame (81) via a hollow rotating shaft (82). The strip feeding device (7) is mounted on the outer surface of the turntable (83) via an angle-adjustable bracket. A gear assembly (84) is mounted on the outer surface of the hollow rotating shaft (82). The gear assembly (84) drives the turntable (83) to rotate via a drive motor (85). A side plate (86) is mounted on one side of the frame (81). The side plate (86) is connected to the strip feeding replacement device (12) via a rotating shaft. The strip supply device (7) and the strip supply replacement device (12) have the same structure. The strip supply device (7) and the angle adjustable bracket, and the strip supply replacement device (12) and the rotating shaft are both provided with quick-release structures. The installation angle of the strip supply device (7) is adjustable, with an adjustment range of 45°-60°.

6. The spiral skeleton forming equipment for aluminum alloy core cross-linked polyethylene photovoltaic cables according to claim 4, characterized in that, A pressure roller mechanism (13) is also provided between the rotating wrapping head (8) and the heating welding device (9). The pressure roller mechanism (13) includes a bracket (131). A second turntable (132) is provided on the surface of the bracket (131). Adjustable pressure rollers (133) are installed on both sides of the second turntable (132) to press the spirally wound strip. The heating and welding device (9) includes a second bracket (91), on the surface of the second bracket (91) is a third turntable (92), and infrared heating rods (93) and conductive slip rings (94) are symmetrically installed on the outer surface of the third turntable (92). The infrared heating rods (93) and conductive slip rings (94) are electrically connected.

7. The spiral skeleton forming equipment for aluminum alloy core cross-linked polyethylene photovoltaic cables according to claim 6, characterized in that, The linkage mechanism (11) includes a linkage rod (111) installed between the second bracket (91) and the frame (81). The outer surface of the linkage rod (111) is connected to three transmission gears (112). The three transmission gears (112) are respectively meshed with toothed rings (113) provided on the outer surfaces of the turntable (83), the second turntable (132) and the third turntable (92). A rotating gear (114) is mounted on the surface of the rotating shaft connected to the strip supply replacement device (12), and the rotating gear (114) meshes with the toothed ring (113) on the surface of the turntable (83).

8. The spiral skeleton forming equipment for aluminum alloy core cross-linked polyethylene photovoltaic cables according to claim 7, characterized in that, The transmission ratio between the toothed ring (113) on the surface of the turntable (83) and the rotating gear (114) is set to a fixed ratio so that the rotation of the strip supply replacement device (12) and the revolution of the turntable (83) remain constant.

9. The spiral skeleton forming equipment for aluminum alloy core cross-linked polyethylene photovoltaic cables according to claim 4, characterized in that, The heating and welding device (9) includes an infrared heating lamp (91) installed on the third turntable (92). When the infrared heating lamp (91) radiates and heats the wrapped strip, the contact point of the adjacent spiral rings forms a heat accumulation effect due to the heat being trapped between the two strips. The temperature is higher than the outer surface temperature of the strip, and a natural temperature difference is formed between the contact point and the outer surface, so as to achieve selective welding with preferential melting and bonding of the contact point.

10. The spiral skeleton forming equipment according to claim 9, characterized in that, The heating welding device (9) further includes: An infrared temperature sensor (95) is installed on the third turntable (92) and rotates synchronously with the infrared heating lamp (91) to monitor the surface temperature of the strip in the heating zone in real time. A PID temperature controller, connected to the infrared temperature sensor, adjusts the heating power of the infrared heating lamps based on temperature feedback to stabilize the surface temperature of the strip within a set range of 80-120℃.

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