A water-blocking aluminum alloy core low-voltage power cable for photovoltaic power generation system and its preparation method

Abstract

The present invention discloses a water-blocking aluminum alloy core low-voltage power cable for photovoltaic power generation systems and a preparation method thereof, specifically relating to the technical field of power cables. The cable comprises a twisted special-shaped aluminum alloy conductor core group, wherein the special-shaped aluminum alloy conductor core group is extruded with an anti-water tree insulation layer on the outside, wherein: a plurality of anti-water tree insulation layers are arranged in a circular array, and an aluminum-plastic composite tape, a polyethylene inner lining layer, an armored steel tape, and a weather-resistant polyethylene outer sheath are sequentially arranged from the inside to the outside according to the axis of the circular array of the anti-water tree insulation layers. The power cable provided by the invention uses a water-blocking adhesive layer and a water-blocking filling layer to block water in the radial and longitudinal directions of the power cable, and at the same time, the aluminum-plastic composite tape, the polyethylene inner lining layer, the armored steel tape, and the weather-resistant polyethylene outer sheath are used to improve the structural strength, water blocking, and weather resistance of the power cable, thereby reducing the formation of water trees and increasing the service life of the power cable.

Description

Technical Field

[0001] The present invention relates to the technical field of power cables, and in particular to a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system and a preparation method thereof. Background Art

[0002] Photovoltaic power generation systems are usually exposed to harsh outdoor environments, such as high humidity, ultraviolet rays, ozone, acid and alkali corrosion, etc. Therefore, in order to ensure the stable operation of photovoltaic power generation systems, the cable performance requirements are extremely high.

[0003] According to the Chinese patent publication number CN113628805B, the publication date is 2023-03-31, which discloses an aluminum alloy conductor cross-linked polyethylene insulated interlocking armored flame-retardant power cable, comprising a core, wherein the core comprises an aluminum alloy conductor, an insulating layer is extruded on the outside of the aluminum alloy conductor, a filling layer is filled between the cores, a wrapping layer is provided on the outside of the filling layer, an inner lining layer is extruded on the outside of the wrapping layer, an interlocking armor layer is covered on the outside of the inner lining layer, and an outer sheath is provided on the outside of the interlocking armor layer.

[0004] The prior art, including the aforementioned patent, uses cross-linked polyethylene as the insulation layer, effectively insulating it, while the flame retardant added to the outer sheath provides effective flame retardancy. This commonly used power cable offers excellent insulation and flame retardancy. However, the use of power cables in photovoltaic power generation systems presents the following issues due to the impact of the operating environment: Relying solely on the outer sheath for waterproofing, the lack of a longitudinal water-blocking design allows for easy penetration of water vapor along the conductor gaps; conventional insulation and outer sheath materials are susceptible to aging and cracking under ultraviolet light and ozone, resulting in a lifespan of less than 20 years; and conventional cross-linked polyethylene is prone to water treeing in humid environments, leading to insulation breakdown. Summary of the Invention

[0005] The purpose of the present invention is to provide a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system and a preparation method thereof, so as to solve the above-mentioned technical problems.

[0006] To achieve the above-mentioned object, the present invention provides the following technical solution: a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system, comprising a twisted special-shaped aluminum alloy conductor core group, wherein the special-shaped aluminum alloy conductor core group is extruded with an anti-water tree insulation layer on the outside, wherein:

[0007] Multiple anti-water tree insulation layers are arranged in a circular array, and an aluminum-plastic composite tape, a polyethylene inner lining layer, an armored steel tape, and a weather-resistant polyethylene outer sheath are arranged in sequence from the inside to the outside according to the axis of the circular array of the anti-water tree insulation layers;

[0008] The aluminum-plastic composite tape is provided with a water-blocking filling layer between the plurality of anti-water-tree insulating layers, and the anti-water-tree insulating layers are provided with a water-blocking glue layer between the special-shaped aluminum alloy conductor core groups.

[0009] Preferably, the special-shaped aluminum alloy conductor core group includes a core single wire and a plurality of winding single wires twisted outside the core single wire.

[0010] A method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system, which is used to achieve the above-mentioned solution of filling a water-blocking adhesive layer between the special-shaped aluminum alloy conductor core groups in the water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system, comprising a stranding table with a tapered opening;

[0011] During the process of conveying the core monofilament and the plurality of winding monofilaments from the wide end to the narrow end of the tapered mouth, the plurality of winding monofilaments adhere to the inner wall of the tapered mouth;

[0012] The inner wall of the tapered opening is provided with a plurality of glue discharge grooves for flowing out the water-blocking glue.

[0013] Preferably, the twisting table is provided with a wire bundling channel and a wire shaping channel which are sequentially distributed at the narrow end of the tapered mouth.

[0014] Preferably, there is a glue storage cavity communicating with the wire bundle path and the shaping wire path, and there is an extrusion cone between the glue storage cavity and the shaping wire path;

[0015] The narrow opening radius of the extrusion cone is equal to the circumferential radius of the shaping wire path.

[0016] Preferably, the inner wall of the extrusion cone is provided with glue spraying ports distributed in a circular array.

[0017] Preferably, an annular compensation groove is arranged at one end of the shaping wire path relative to the extrusion cone.

[0018] Preferably, an elastic plate obliquely extending to the outside of the slot is fixedly mounted on the inner wall of the glue discharge groove, and the elastic plate is swept and moved toward the inside of the slot of the glue discharge groove during the movement around the monofilament to squeeze out the water-blocking glue.

[0019] Preferably, it further includes a liquid storage groove, and the monofilament is moved and swept through the glue discharge groove and the liquid storage groove in sequence.

[0020] Preferably, the upper surface of the low-position plate to which the end portion of the elastic plate is fixedly mounted is lower than the upper surface of the elastic plate.

[0021] In the above technical solution, the present invention provides a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system and a preparation method thereof, which has the following beneficial effects: by utilizing the water-blocking adhesive layer on the special-shaped aluminum alloy conductor core group and the water-blocking filling layer filled between multiple anti-water tree insulation layers, the radial water-blocking filling layer and the longitudinal water-blocking adhesive layer of the power cable are water-blocked, and at the same time, the aluminum-plastic composite tape, polyethylene lining layer, armored steel tape and weather-resistant polyethylene outer sheath are used to improve the structural strength, water blocking and weather resistance of the power cable, thereby reducing the generation of water trees and enhancing the service life of the power cable. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0023] Figure 1 A schematic diagram of the overall cross-sectional structure of a power cable provided by an embodiment of the present invention;

[0024] Figure 2 A schematic diagram of the overall structure of a twisting table provided in an embodiment of the present invention;

[0025] Figure 3 A schematic diagram of the structure of a twisting table provided in an embodiment of the present invention;

[0026] Figure 4 A schematic diagram of the cross-sectional structure of a twisting table provided in an embodiment of the present invention;

[0027] Figure 5 A schematic structural diagram of a special-shaped aluminum alloy conductor core group provided in an embodiment of the present invention;

[0028] Figure 6 A schematic diagram of a tapered port cross-sectional structure provided by an embodiment of the present invention;

[0029] Figure 7 A schematic diagram of the cross-sectional structure of a tapered mouth portion provided by an embodiment of the present invention;

[0030] Figure 8 A schematic diagram of a partial cross-sectional structure of a twisting table provided in an embodiment of the present invention;

[0031] Figure 9 The embodiment of the present invention provides Figure 4 A in the middle is an enlarged structural diagram;

[0032] Figure 10 The embodiment of the present invention provides Figure 4 The enlarged structural diagram at B in the middle;

[0033] Figure 11 The embodiment of the present invention provides Figure 6 The enlarged structural diagram at C in the middle;

[0034] Figure 12 The embodiment of the present invention provides Figure 7 Enlarged structural diagram at point D in the middle.

[0035] Description of reference numerals:

[0036] 1. Weather-resistant polyethylene outer sheath; 2. Stranding table; 3. Ring; 4. Core monofilament; 5. Elastic plate; 6. Airbag; 11. Armored steel tape; 12. Polyethylene liner; 13. Aluminum-plastic composite tape; 14. Water-blocking filling layer; 15. Water-tree-resistant insulation layer; 16. Water-blocking adhesive layer; 21. Conical port; 22. Glue injection hose; 23. Front recovery tank; 24. Collection chamber; 25. Rear recovery tank; 26. Drain pipe ; 27. Wire bundle channel; 28. Shaping wire channel; 31. Compensation channel; 32. Annular compensation groove; 33. Glue spray port; 34. Extrusion cone; 35. Glue storage chamber; 36. Flow channel; 37. Glue discharge groove; 38. Flow chamber; 39. Liquid storage groove; 41. Winding single wire; 42. Large angle; 43. Small angle; 44. Finished state; 51. Low plate; 52. Upper plate; 53. Lower plate; 61. Opening. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure. Example

[0038] A water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system comprises a twisted special-shaped aluminum alloy conductor core group, the outer side of which is extruded with an anti-water tree insulation layer 15, wherein:

[0039] Multiple anti-water tree insulation layers 15 are arranged in a circular array, and along the axis of the circular array of the anti-water tree insulation layers 15, an aluminum-plastic composite tape 13, a polyethylene inner liner 12, an armored steel tape 11, and a weather-resistant polyethylene outer sheath 1 are sequentially arranged from the inside to the outside.

[0040] A water-blocking filling layer 14 is filled between the plurality of water-tree resistant insulating layers 15 in the aluminum-plastic composite tape 13 , and a water-blocking adhesive layer 16 is filled between the water-tree resistant insulating layers 15 and the special-shaped aluminum alloy conductor core groups.

[0041] Specifically, such as Figure 1 As shown, a stranding machine is used to strand the shaped aluminum alloy conductor core group, and a water-blocking adhesive filling machine is used to evenly apply hot-melt water-blocking adhesive to the surface of the stranded shaped aluminum alloy conductor core group to form a water-blocking filling layer 14. The water-blocking adhesive uses a modified polyurethane resin and has a viscosity of 5000 cps.

[0042] An extruder then extrudes the anti-water-tree insulation layer 15 onto the glue-filled special-shaped aluminum alloy conductor core assembly. The special-shaped aluminum alloy conductor core assembly achieves a fill factor of ≥95% compared to the anti-water-tree insulation layer 15. The special-shaped aluminum alloy conductor core assembly utilizes trapezoidal aluminum alloy monofilaments with a twist pitch ratio of 12-15.

[0043] The water-tree-resistant insulation layer 15 is made of 2.0mm thick, cross-linked polyethylene (XLPE) with anti-water-tree properties. Nano-silica and an anti-water-tree agent (such as a polyethylene glycol derivative) are added. The cross-linking process involves extrusion followed by electron beam cross-linking to ensure a cross-linking degree of ≥85% and thermal elongation of ≤50%.

[0044] The water-blocking filling layer 14 is a water-blocking yarn of super absorbent polymer fibers, which is evenly and tightly wrapped around the outer sides of the plurality of water-tree resistant insulating layers 15 by automated equipment, thereby achieving the effect of preventing moisture from invading the power cable.

[0045] Then, a wrapping machine is used to wrap the outer sides of the plurality of water-tree resistant insulation layers 15 with aluminum-plastic composite tapes 13 (wrapping thickness ≥ 0.15 mm), and the aluminum layer thickness of the wrapped aluminum-plastic composite tapes 13 is 20 μm.

[0046] After wrapping the aluminum-plastic composite tape 13, the extruder equipment is used again to extrude the polyethylene liner 12 added with water-blocking carbon black onto the aluminum-plastic composite tape 13. Then, the armored steel tape 11 is wrapped onto the polyethylene liner 12 through the armor wrapping machine.

[0047] The weather-resistant polyethylene outer sheath 1 includes 2% benzotriazole as an anti-ultraviolet agent, 1% nano-montmorillonite as an acid- and alkali-resistant filler, and 2.5% p-phenylenediamine as an anti-ozonant. The surface of the weather-resistant polyethylene outer sheath 1 is treated with ultraviolet light curing to form a dense protective layer. The thickness of the weather-resistant polyethylene outer sheath 1 is ≥1.8 mm.

[0048] Therefore, through the use of trapezoidal aluminum alloy monofilaments, water-blocking adhesive, and water-blocking yarn, high conductivity is achieved, as well as the integration of longitudinal waterproofing of the water-blocking adhesive and radial waterproofing of the water-blocking yarn. The anti-water-tree insulation layer 15 utilizes water-tree-resistant cross-linked polyethylene combined with an aluminum-plastic composite tape 13 to achieve both water-tree resistance and radial waterproofing. The use of a weather-resistant polyethylene outer sheath 1 and protective armored steel tape 11 effectively enhances the cable's weather resistance and protective strength, making it more suitable for use in photovoltaic power generation systems in environments with high humidity, UV rays, ozone, and acid and alkali corrosion.

[0049] In the above technical solution, by utilizing the water-blocking adhesive layer 16 on the special-shaped aluminum alloy conductor core group and the water-blocking filling layer 14 filled between multiple anti-water tree insulation layers 15, the radial water-blocking filling layer 14 and the longitudinal water-blocking adhesive layer 16 of the power cable are water-blocked. At the same time, the aluminum-plastic composite tape 13, the polyethylene liner 12, the armored steel tape 11 and the weather-resistant polyethylene outer sheath 1 are used to improve the structural strength, water blocking and weather resistance of the power cable, thereby reducing the generation of water trees and extending the service life of the power cable.

[0050] As an embodiment further provided by the present invention, the special-shaped aluminum alloy conductor core group includes a core single wire 4 and a plurality of winding single wires 41 twisted around the outer side of the core single wire 4 .

[0051] Specifically, by using the core monofilament 4 as the stable axial core of the special-shaped aluminum alloy conductor core group, and cooperating with multiple winding monofilaments 41 stranded on the core monofilament 4 with the core monofilament 4 as the axis, the entire twisted structure can better withstand pressure and tension, reducing the risk of wear and breakage. At the same time, it can effectively reduce deformation when external forces are applied. The core monofilament 4 is the axis, and the multiple winding monofilaments 41 are stranded on the core monofilament 4. This can reduce the problem of air or moisture being trapped in the power cable and causing cavitation. In this case, when the special-shaped aluminum alloy conductor core group is coated with water-blocking adhesive from the outside, the water-blocking adhesive can directly fill the gap between the winding monofilament 41 and the core monofilament 4. Compared with the dispersed stranded power cable, when the water-blocking adhesive is applied to the dispersed stranded power cable, air or moisture will be trapped in the adhesive layer during the coating process, forming cavitation, which will reduce the longitudinal water-blocking effect of the power cable. For each anti-water-tree insulation layer 15, there are six winding monofilaments 41 and one core monofilament 4. Example

[0052] like Figure 1-12 As shown, a method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system includes a twisting table 2 with a tapered opening 21;

[0053] During the process of the core monofilament 4 and the plurality of winding monofilaments 41 being transported from the wide end to the narrow end of the tapered mouth 21, the plurality of winding monofilaments 41 adhere to the inner wall of the tapered mouth 21;

[0054] The inner wall of the tapered opening 21 is provided with a plurality of glue discharge grooves 37 for the water-blocking glue to flow out.

[0055] Specifically, multiple glue discharge grooves 37 are arranged in a circular array with the axis of the tapered mouth 21. Heated water-blocking glue is pumped into the multiple glue discharge grooves 37 by a water-blocking glue filling machine, and then the water-blocking glue flows out along the multiple glue discharge grooves 37 respectively, and is transported from the wide end to the narrow end of the tapered mouth 21 through the core monofilament 4 and the multiple winding monofilaments 41. At this time, the core monofilament 4 and the multiple winding monofilaments 41 are twisted into strands in cooperation with the twisting machine, and then the stranded special-shaped aluminum alloy conductor core group is pulled and moved by the traction machine to facilitate the implementation of the next step.

[0056] Furthermore, when the twisting machine rotates the core monofilament 4 and the multiple winding monofilaments 41 to twist them into strands, the core monofilament 4 moves stably along the axis of the tapered mouth 21, and the multiple winding monofilaments 41 are driven by the twisting machine to rotate and rotate along the inner wall of the tapered mouth 21. The multiple winding monofilaments 41 will scrape the inner wall of the tapered mouth 21 during the rotation. At this time, part of the water-blocking glue discharged along the glue discharge groove 37 flows on the inner wall of the tapered mouth 21, and the other part overflows the glue discharge groove 37 and is scraped up by the rotating winding monofilament 41 and adheres to the winding monofilament 41. At the same time, the water-blocking glue on the inner wall of the tapered mouth 21 is also scraped up when the winding monofilament 41 rotates, so that the multiple winding monofilaments 41 are attached to the water-blocking glue when they are twisted, and then the winding monofilament 41 moves from the wide end to the narrow end of the tapered mouth 21, so that the multiple winding monofilaments 41 gradually approach and wrap around the core monofilament 4 as they move. When multiple winding monofilaments 41 simultaneously approach the core monofilament 4, the water-blocking adhesive on the multiple winding monofilaments 41 will aggregate. As the gap between two adjacent winding monofilaments 41 narrows, and the distance between the winding monofilaments 41 and the core monofilament 4 further narrows, the excess water-blocking adhesive is squeezed due to the shrinkage of the multiple winding monofilaments 41. The squeezed water-blocking adhesive will flow along the gaps between the two winding monofilaments 41 and between the winding monofilaments 41 and the core monofilament 4, thereby quickly filling the gaps between the two winding monofilaments 41 and between the winding monofilaments 41 and the core monofilament 4. At the same time, the air between the two winding monofilaments 41 and between the winding monofilaments 41 and the core monofilament 4 is pushed out by the fast-flowing water-blocking adhesive, thereby further reducing cavitation in the special-shaped aluminum alloy conductor core group and improving the uniformity and filling rate of the water-blocking adhesive coating on the special-shaped aluminum alloy conductor core group. Compared with the traditional method of directly applying water-blocking adhesive to the power cable from the outside, this method can effectively improve the filling rate of the water-blocking adhesive in the power cable. Furthermore, the mechanical force generated by the twisting of the core monofilament 4 and the plurality of winding monofilaments 41 can effectively replace existing means such as a pressure pump, thereby saving production costs and improving the coating effect of the water-blocking adhesive.

[0057] As another embodiment provided by the present invention, the stranding table 2 is provided with a wire bundling path 27 and a wire shaping path 28 which are sequentially distributed at the narrow end of the tapered opening 21 .

[0058] Specifically, the wire bundle duct 27 is located on the narrow end of the conical mouth 21, and the shaping wire duct 28 is located on the side of the wire bundle duct 27 opposite to the conical mouth 21. The inner diameter of the wire bundle duct 27 is larger than the inner diameter of the shaping wire duct 28. When the core monofilament 4 and the multiple winding monofilaments 41 pass through the conical mouth 21, the multiple winding monofilaments 41 enter the wire bundle duct 27 and the shaping wire duct 28 in sequence when passing through the narrow end of the conical mouth 21. Under the support and limitation of the wire bundle duct 27 and the shaping wire duct 28, the winding monofilaments 41 are respectively restricted to the following three states: inside the conical mouth 21; between the wire bundle duct 27 and the shaping wire duct 28; and inside the shaping wire duct 28. Figure 5 As shown, when the monofilament 41 is in the tapered mouth 21, the angle between the multiple monofilaments 41 and the core monofilament 4 is the largest and is in a large angle 42, and when the monofilament 41 is between the bundle wire duct 27 and the shaping wire duct 28, the angle between the multiple monofilaments 41 and the core monofilament 4 becomes smaller and is in a small angle 43, and when the monofilament 41 is in the shaping wire duct 28, due to the limitation of the shaping wire duct 28, the multiple monofilaments 41 are respectively attached to the core monofilament 4 to be in a completed state 44.

[0059] By switching multiple winding monofilaments 41 from a large angle 42 to a small angle 43, and then switching to the completed state 44, the water-blocking glue can flow better between the wire bundle 27 and the shaping wire duct 28 when the multiple winding monofilaments 41 are gathered, so as to improve the filling effect of the water-blocking glue during twisting, and the excess water-blocking glue squeezed out can remain between the wire bundle duct 27 and the shaping wire duct 28 to wrap the entire core monofilament 4 and the multiple winding monofilaments 41, so that the water-blocking glue is restricted and the immersion wrapping of the special-shaped aluminum alloy conductor core group is achieved, thereby improving the uniformity of filling the special-shaped aluminum alloy conductor core group, and the water-blocking glue squeezed out by the multiple winding monofilaments 41 along the wire bundle duct 27 will enter the tapered mouth 21. Through the rotation and twisting of the multiple winding monofilaments 41, the problem of water-blocking glue overflowing from the tapered mouth 21 and causing pollution and waste can be reduced, so as to make full use of the water-blocking glue.

[0060] As another embodiment provided by the present invention, there is a glue storage cavity 35 between the wire bundle path 27 and the shaping wire path 28, which is in communication with the two. There is an extrusion cone 34 between the glue storage cavity 35 and the shaping wire path 28.

[0061] The narrow opening radius of the extrusion cone 34 is equal to the circumferential radius of the shaping wire path 28 .

[0062] Specifically, such as Figure 9As shown, when multiple winding monofilaments 41 move from the narrow mouth of the extrusion cone 34 into the shaping wire channel 28, the winding monofilaments 41 are squeezed due to the combined action of the shaping wire channel 28 and the narrow mouth of the extrusion cone 34, and the winding monofilaments 41 are tightly attached to the core monofilament 4 to be in a completed state 44.

[0063] Furthermore, the glue storage cavity 35 is located between the wire bundle path 27 and the shaping wire path 28. When the multiple winding monofilaments 41 are gathered together, the water-blocking glue overflows from between the multiple winding monofilaments 41 and gathers in the glue storage cavity 35. When the glue storage cavity 35 is filled with the water-blocking glue, the water-blocking glue will wrap the core monofilament 4 and the multiple winding monofilaments 41 in the glue storage cavity 35, thereby comprehensively filling the special-shaped aluminum alloy conductor core group with glue. At the same time, due to the viscosity between the special-shaped aluminum alloy conductor core group and the water-blocking glue, when the glue storage cavity 35 is filled with the water-blocking glue, the core monofilament 4 and the multiple winding monofilaments 41 in the glue storage cavity 35 will be filled with glue. As the shaped aluminum alloy conductor core assembly moves into the extrusion cone 34, the water-blocking adhesive is pulled into the shaping wire path 28 by the shaped aluminum alloy conductor core assembly, thereby driving the water-blocking adhesive to converge within the extrusion cone 34. As the space within the extrusion cone 34 gradually narrows, the pressure of the water-blocking adhesive at the narrow end of the extrusion cone 34 increases. The squeezed water-blocking adhesive flows into the gaps between the multiple winding monofilaments 41 in the low-pressure area, further filling the gaps remaining in the shaped aluminum alloy conductor core assembly with adhesive. This improves the quality of adhesive coating on the shaped aluminum alloy conductor core assembly.

[0064] As another embodiment provided by the present invention, the inner wall of the extrusion cone 34 is provided with glue spraying ports 33 distributed in a circular array.

[0065] Specifically, the glue spraying port 33 is located on the inner wall of the extrusion cone 34 and close to the narrow mouth of the extrusion cone 34. A glue injection tube 22 is fixedly welded on the twisting table 2. The ring 3 opened in the twisting table 2 is connected to the glue injection tube 22, and multiple glue spraying ports 33 are respectively connected to the ring 3. The glue injection tube 22 is connected to the water-blocking glue filling machine and the heated water-blocking glue is injected into it by the pressure pump on the water-blocking glue filling machine. Then the water-blocking glue enters the glue spraying port 33 along the ring 3. At this time, Figure 8 The solid arrow in the middle shows the approximate flow direction of the water-blocking glue squeezed out of the glue spray port 33. When the water-blocking glue is sprayed out along the glue spray port 33, part of it will flow between the multiple winding monofilaments 41, another part will enter the glue storage cavity 35, and another part of the water-blocking glue squeezed out from between the multiple winding monofilaments 41 will flow again between the multiple winding monofilaments 41 and enter the tapered port 21, so as to increase the range of the winding monofilaments 41 impregnated with glue, thereby reducing the generation of cavitation. Figure 8The dotted arrow in the middle indicates the direction in which the water-blocking glue is moved by the multiple winding monofilaments 41 and the core monofilament 4 in the special-shaped aluminum alloy conductor core group, and the direction in which the water-blocking glue flows when the multiple winding monofilaments 41 extrude the water-blocking glue. Through the viscosity between the special-shaped aluminum alloy conductor core group and the water-blocking glue, the special-shaped aluminum alloy conductor core group drives the water-blocking glue into the extrusion cone 34 and the glue storage cavity 35, and the water-blocking glue gathered in the extrusion cone 34 will be simultaneously subjected to the entrainment thrust during the movement of the special-shaped aluminum alloy conductor core group and the pressure of the water-blocking glue squeezed out of the glue spray port 33. At this time, two pressure points act on the extrusion cone 34 in the same area, thereby causing the water-blocking glue under high pressure to flow to the low-pressure area, so that the area in the low-pressure area that is not completely filled with the water-blocking glue is filled by the rapid flow of water-blocking glue in the high-pressure area, so as to further improve the filling effect of the water-blocking glue.

[0066] At the same time Figure 9 As shown, the glue storage cavity 35 is connected to multiple glue discharge grooves 37 through multiple flow channels 36 opened in the twisting table 2. The water-blocking glue in the glue storage cavity 35 will flow to the multiple glue discharge grooves 37 along the multiple flow channels 36, so that the water-blocking glue can flow in the multiple glue discharge grooves 37 to facilitate the scraping and spreading of glue by multiple winding monofilaments 41.

[0067] As the best embodiment provided by the present invention, an annular compensation groove 32 is arranged at one end of the shaping wire channel 28 opposite to the extrusion cone 34 .

[0068] Specifically, such as Figure 4 As shown, a front recovery groove 23 is provided on the inner wall of the tapered mouth 21 near the wide mouth end, a rear recovery groove 25 is provided on the twisting table 2 on one side of the annular compensation groove 32, a collecting chamber 24 connected to the front recovery groove 23 and the rear recovery groove 25 is provided on the twisting table 2, and a drainage pipe 26 connected to the collecting chamber 24 is fixedly installed on the twisting table 2, which is connected to the feed port on the water-blocking glue filling machine through the drainage pipe 26, so as to cooperate with the corresponding pressure pump so that the water-blocking glue recovered from the front recovery groove 23 and the rear recovery groove 25 can be recycled again, so as to reduce the waste and pollution of the water-blocking glue.

[0069] At the same time, if Figure 10 and Figure 4As shown, a compensation channel 31 is provided on the twisting table 2, with its two ends respectively connected to the annular compensation groove 32 and the ring 3. The water-blocking glue in the ring 3 flows along the compensation channel 31 to the annular compensation groove 32, so that when the special-shaped aluminum alloy conductor core group passes through the annular compensation groove 32, a certain thickness of water-blocking glue will be formed on the outer wall of the special-shaped aluminum alloy conductor core group. This solves the problem of missing or incomplete distribution of water-blocking glue caused by extrusion friction between the special-shaped aluminum alloy conductor core group and the inner wall of the shaping wire path 28 when the special-shaped aluminum alloy conductor core group is pulled out of the shaping wire path 28. At the same time, a certain thickness of water-blocking glue is formed on the outer wall of the special-shaped aluminum alloy conductor core group through the annular compensation groove 32, which can better contact with the anti-water tree insulation layer 15, thereby reducing the problem of gaps between the anti-water tree insulation layer 15 and the special-shaped aluminum alloy conductor core group.

[0070] As another embodiment provided by the present invention, an elastic plate 5 is fixedly installed on the inner wall of the glue discharge groove 37 and extends obliquely to the outside of the groove. During the movement around the monofilament 41, the elastic plate 5 is swept and moved toward the inside of the groove of the glue discharge groove 37 to squeeze out the water-blocking glue.

[0071] Specifically, anti-overflow baffles are fixedly installed on the opposite sides of the elastic plate 5. In the default state, the elastic force of the elastic plate 5 will cause the elastic plate 5 to tilt and extend to the outside of the slot and be located on the moving path of the winding monofilament 41. In the default state, one end of the elastic plate 5 is attached to the inner wall of the glue discharge groove 37. At this time, the elastic plate 5 is used to achieve shielding and sealing of the glue discharge groove 37. When the winding monofilament 41 rotates and twists and sweeps the elastic plate 5, the elastic plate 5 is squeezed by the winding monofilament 41 to move toward the inside of the glue discharge groove 37. At this time, the elastic plate 5 is deformed to open the glue discharge groove 37, and at the same time, the elastic plate 5 cooperates with the elastic plate 5 to seal the glue discharge groove 37. The water-blocking adhesive in the glue discharge groove 37 is squeezed and the pressure of the water-blocking adhesive in the glue discharge groove 37 is increased so that the water-blocking adhesive is quickly squeezed out of the glue discharge groove 37. Then, as the winding monofilament 41 passes by, the water-blocking adhesive is scraped onto the winding monofilament 41. When the winding monofilament 41 separates from the elastic plate 5 and the elastic plate 5 recovers its deformation, the glue discharge groove 37 is closed. The glue discharge groove 37 is controlled to open when the winding monofilament 41 passes by and close when the winding monofilament 41 passes by. This prevents the glue discharge groove 37 from flowing for a long time, resulting in problems such as uncontrolled glue overflow and contamination, so as to reasonably and effectively utilize the water-blocking adhesive. The elastic plate 5 is made of elastic stainless steel.

[0072] As another embodiment provided by the present invention, it also includes a liquid storage groove 39, and moves around the monofilament 41 and sweeps through the glue discharge groove 37 and the liquid storage groove 39 in sequence.

[0073] Specifically, an upper plate 52 is fixedly installed at the end of the elastic plate 5, and a lower plate 53 is fixedly installed at the bottom end of the upper plate 52. A flow cavity 38 connected to the glue discharge groove 37 is provided on the inner wall of the liquid storage groove 39, and an airbag 6 is fixedly installed on the inner wall of the glue discharge groove 37 on the side of the flow cavity 38. An opening 61 is provided on the airbag 6, and the airbag 6 is located between the elastic plate 5 and the liquid storage groove 39. In the default state, the elastic plate 5 extends obliquely to the outside of the slot, and the lower plate 53 on the elastic plate 5 squeezes the airbag 6 to deform to close the flow cavity 38. When the elastic plate 5 is pressed downward by the monofilament 41 to move toward the inside of the slot of the glue discharge groove 37, the lower plate 53 is separated from the airbag 6, and the upper plate 52 begins to contact the airbag 6, as shown in FIG. Figure 11 and Figure 12 As shown, when the upper plate 52 contacts the airbag 6, the squeezing force on the airbag 6 is reduced, and then the airbag 6 is reset to release the closure of the flow cavity 38, and at the same time, the water-blocking glue in the glue discharge groove 37 flows along the flow cavity 38 to the liquid storage groove 39, and part of the water-blocking glue in the liquid storage groove 39 enters the airbag 6 along the opening 61, and then accompanied by the rotational movement of the monofilament 41, the monofilament 41 is separated from the elastic plate 5 and the water-blocking glue overflowing from the liquid storage groove 39 is scraped, and at the same time, the elastic plate 5 is reset to squeeze the airbag 6 again. At this time, the water-blocking glue in the airbag 6 is squeezed by the lower plate 53 to be ejected from the opening 61 and adhere to the monofilament 41, thereby increasing the amount and uniformity of the water-blocking glue adhered to the monofilament 41.

[0074] As a further optimal embodiment provided by the present invention, the upper surface of the low-position plate 51 fixedly installed at the end of the elastic plate 5 is lower than the upper surface of the elastic plate 5 .

[0075] Specifically, according to Figure 12For reference, the upper surface of the low plate 51 is lower than the upper surface of the elastic plate 5. When the monofilament 41 squeezes the elastic plate 5, the elastic plate 5 and the low plate 51 simultaneously move toward the inside of the notch of the glue discharge groove 37. As the monofilament 41 moves and the flow cavity 38 is opened, the water-blocking glue in the glue discharge groove 37 flows toward the liquid storage groove 39 and the low plate 51. Then, when the monofilament 41 is transferred from the elastic plate 5 to the low plate 51, due to the height difference between the elastic plate 5 and the low plate 51, the elastic reset of the elastic plate 5 allows the low plate 51 to quickly approach the monofilament 41 and strike the monofilament 41 when it contacts the monofilament 41, generating vibration. At the same time, the water-blocking adhesive remaining on the upper surface of the lower plate 51 is quickly pushed onto the winding monofilament 41. At the same time, the lower plate 53 squeezes the airbag 6 so that the water-blocking adhesive sprayed out from the opening 61 adheres to the winding monofilament 41, thereby making the water-blocking adhesive adhere to the winding monofilament 41 more fully. The vibration of the winding monofilament 41 and the convergence of multiple winding monofilaments 41 bring the multiple winding monofilaments 41 twisted between the bundle path 27 and the shaping path 28 together to squeeze the water-blocking adhesive. At the same time, the vibration expels the air between the multiple winding monofilaments 41 and between the winding monofilament 41 and the core monofilament 4, thereby reducing the generation of cavitation. This improves the quality and filling rate of the water-blocking adhesive coating.

[0076] Working principle: When the core monofilament 4 and multiple winding monofilaments 41 are transported from the wide end of the tapered mouth 21 to the narrow end, the multiple winding monofilaments 41 are accompanied by the rotation process to scrape the inner wall of the tapered mouth 21. At this time, the water-blocking glue discharged along the glue discharge groove 37 is scraped up by the rotating winding monofilament 41 and adheres to the winding monofilament 41. When the winding monofilament 41 squeezes the elastic plate 5, the elastic plate 5 and the low-position plate 51 move toward the inside of the glue discharge groove 37 at the same time, and the flow cavity 38 is opened to allow the water-blocking glue in the glue discharge groove 37 to flow to the liquid storage groove 39 and the low-position plate 51. Then, when the winding monofilament 41 is transferred from the elastic plate 5 to the low-position plate 51, the elastic plate 5 elastically resets, and the low-position plate 51 knocks on the winding monofilament 41 to generate vibration and push the water-blocking glue onto the winding monofilament 41. At the same time, the lower plate 53 cooperates to squeeze the airbag 6 so that the opening 61 sprays out the water-blocking glue and adheres to the winding monofilament 41.

[0077] Then, the multiple winding monofilaments 41 gradually move closer and are wrapped around the core monofilament 4. At the same time, the water-blocking glue on the multiple winding monofilaments 41 will aggregate. At this time, the excess water-blocking glue is squeezed due to the shrinkage of the multiple winding monofilaments 41 to fill the gaps between the special-shaped aluminum alloy conductor core groups. The vibration generated by the low-position plate 51 knocking on the winding monofilaments 41 is used to expel the air in the gaps between the special-shaped aluminum alloy conductor core groups, thereby reducing cavitation in the special-shaped aluminum alloy conductor core groups.

[0078] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system, characterized in that: The water-blocking aluminum alloy core low-voltage power cable comprises a twisted special-shaped aluminum alloy conductor wire core group, and a water-blocking adhesive layer (16) is filled between the special-shaped aluminum alloy conductor wire core groups; The special-shaped aluminum alloy conductor wire core group comprises a core monofilament (4) and a plurality of winding monofilaments (41) twisted outside the core monofilament (4); The preparation method of the special-shaped aluminum alloy conductor wire core group filled with a water-blocking adhesive layer (16) comprises a twisting table (2) with a tapered opening (21) formed thereon; During the process of conveying the core monofilament (4) and the plurality of winding monofilaments (41) from the wide end to the narrow end of the tapered mouth (21), the plurality of winding monofilaments (41) adhere to the inner wall of the tapered mouth (21); The inner wall of the tapered opening (21) is provided with a plurality of glue discharge grooves (37) for flowing out the water-blocking glue; The twisting table (2) is provided with a wire bundle path (27) and a shaping wire path (28) which are sequentially distributed at the narrow end of the tapered opening (21); The inner diameter of the wire bundle path (27) is larger than the inner diameter of the shaping wire path (28); when the core monofilament (4) and the plurality of winding monofilaments (41) pass through the tapered opening (21), the plurality of winding monofilaments (41) enter the wire bundle path (27) and the shaping wire path (28) in sequence when passing through the narrow end of the tapered opening (21); There is a glue storage cavity (35) between the wire bundle path (27) and the shaping wire path (28) and is in communication with both of them. There is an extrusion cone (34) between the glue storage cavity (35) and the shaping wire path (28); The narrow opening radius of the extrusion cone (34) is equal to the circumferential radius of the shaping wire path (28); The inner wall of the extrusion cone (34) is provided with glue spraying ports (33) distributed in a circumferential array.

2. The method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system according to claim 1, characterized in that: An annular compensation groove (32) is arranged at one end of the shaping wire channel (28) opposite to the extrusion cone (34).

3. The method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system according to claim 1, characterized in that: An elastic plate (5) is fixedly mounted on the inner wall of the adhesive discharge groove (37) and extends obliquely to the outside of the groove opening. During the movement of the monofilament (41), the elastic plate (5) is swept and moved toward the inside of the groove opening of the adhesive discharge groove (37) to press out the water-blocking adhesive.

4. The method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system according to claim 3, characterized in that: It also includes a liquid storage groove (39), and moves around the monofilament (41) and sweeps through the glue discharge groove (37) and the liquid storage groove (39) in sequence.

5. The method for preparing a water-blocking aluminum alloy core low-voltage power cable for a photovoltaic power generation system according to claim 3, characterized in that: The upper surface of the low-position plate (51) fixedly mounted at the end of the elastic plate (5) is lower than the upper surface of the elastic plate (5).

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