Double-core water-blocking weather-proof photovoltaic direct-current cable and preparation method thereof

Abstract

The invention discloses a double-core water-blocking weather-proof photovoltaic direct-current cable and a preparation method thereof, and the cable comprises two cable bodies, and is characterized in that each cable body is provided with a tinned conductor, water-blocking glue, an insulating layer, a water-blocking tape and a sheath layer from inside to outside in sequence; a connecting rib is fixedly arranged between the two sheath layers; the water-blocking tape is arranged outside the insulating layer in a double-layer wrapping mode, and the double-layer water-blocking tape is composed of a PET base material and acrylic acid glue. The insulating layer is arranged in a double-layer mode, the inner layer is XLPE added with 3% of nanometer aluminum hydroxide, the outer layer is XLPE added with 5% of nanometer carbon black, the space between the tinned conductor and the insulating layer is coated with hot-melt water-blocking glue for longitudinal water blocking, the space between the tinned conductor and the insulating layer is provided with a double-layer water-blocking tape for radial water blocking, the water-blocking performance of the cable is effectively improved, the inner layer of the insulating layer is XLPE added with 3% of nanometer aluminum hydroxide, and therefore the water-blocking performance of the cable is effectively improved. And the outer layer is made of anti-ultraviolet and water-resistance XLPE added with 5% of nano carbon black, so that the water resistance and the anti-ultraviolet performance of the cable are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cables, and particularly relates to a double-core water-blocking and weather-resistant photovoltaic DC cable and a preparation method thereof. Background Art

[0002] Single-core photovoltaic cables need to be laid in pairs, resulting in low installation and construction efficiency. Moreover, the paired laying structure is prone to insulation layer wear and short circuit due to mechanical stress. In an outdoor environment, the cable sheath is prone to aging and cracking (ultraviolet rays, ozone, high and low temperature cycles), with a short lifespan. Additionally, the cable has poor longitudinal water-blocking ability, and water vapor penetration causes a decrease in insulation resistance, leading to photovoltaic inverter alarms and even cable breakdown.

[0003] Summary of the Invention The purpose of the present invention is to provide a double-core water-blocking and weather-resistant photovoltaic DC cable and a preparation method thereof to solve the above deficiencies in the prior art.

[0004] To achieve the above purpose, the present invention provides the following technical solutions: A double-core water-blocking and weather-resistant photovoltaic DC cable includes two cable bodies. From the inside to the outside, each cable body sequentially comprises a tinned conductor, a water-blocking gel, an insulating layer, a water-blocking tape, and a sheath layer; A connecting rib is fixedly arranged between the two sheath layers; The water-blocking tape is wound around the insulating layer in a double-layer manner, and the double-layer water-blocking tapes are respectively a PET substrate and an acrylic glue; The insulating layer is arranged in a double-layer manner, with the inner layer being XLPE added with 3% nano-aluminum hydroxide and the outer layer being XLPE added with 5% nano-carbon black.

[0005] A preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable is used to prepare the above double-core water-blocking and weather-resistant photovoltaic DC cable, and includes a base, a furnace body, and a support table. A column is fixedly arranged on the base, a rotating tube is rotatably arranged on the column, a sliding tube is sleeved outside the rotating tube, and when the cable reel releases the cable, the sliding tube slides as the rotating tube rotates; A plurality of telescopic columns are slidably arranged on the sliding tube, a tensioning block is fixedly arranged on the telescopic column, the tensioning block abuts against the cable reel, a support track is slidably arranged on the rotating tube, a ball is rotatably arranged on the telescopic column, and the ball is rotatably arranged in the support track; A friction plate is fixedly arranged on the telescopic column, and the friction plate is in frictional contact with the rotating tube; It further includes a reverse pulling assembly, which is used to reverse the rotation of the rotating tube and straighten the cable when the tensioning block abuts against the cable reel.

[0006] Preferably, a first spring is arranged between the telescopic column and the sliding tube, and two ends of the first spring are respectively fixedly connected to the telescopic column and the sliding tube.

[0007] Preferably, a reciprocating pipe is slidably arranged on the upright post, a push rod is rotatably arranged on the reciprocating pipe, a guide post is fixedly arranged on the push rod, a slider is fixedly arranged on the support rail, a guide groove is arranged on the slider, and the guide post is slidably arranged in the guide groove; The guide groove includes a straight portion and an inclined portion.

[0008] Preferably, the anti-pull assembly includes a reverse pipe fixedly arranged on the rotating pipe, an arc plate is slidably arranged on the reverse pipe, a first inclined portion is arranged on the arc plate, a convex block is fixedly arranged on the reciprocating pipe, and the convex block is slidably arranged between the first inclined portion and the reverse pipe.

[0009] Preferably, a second inclined portion is arranged on the arc plate, and an inclined surface adapted to the second inclined portion is arranged on the reverse pipe.

[0010] Preferably, a second spring is arranged between the arc plate and the reverse pipe, and two ends of the second spring are respectively fixedly connected with the arc plate and the reverse pipe.

[0011] Preferably, a rotating member is rotatably arranged on the upright post, and the rotating member is in threaded connection with the reciprocating pipe.

[0012] Preferably, support rods are fixedly arranged on both sides of the base, and traction wheels are rotatably arranged on the support rods.

[0013] Preferably, a fixing groove is arranged on one of the support rods.

[0014] In the above technical solution, the beneficial effects of a double-core water-blocking and weather-resistant photovoltaic DC cable and its preparation method provided by the present invention are as follows: 1. By coating a hot-melt water-blocking adhesive between the tinned conductor and the insulating layer as longitudinal water-blocking, and by providing a double-layer water-blocking tape as radial water-blocking, the water-blocking performance is effectively improved. The inner layer of the insulating layer is XLPE added with 3% nano-aluminum hydroxide, which effectively improves the flame-retardant performance. The outer layer is XLPE added with 5% nano-carbon black for anti-ultraviolet and water-blocking, which improves its water-blocking and anti-ultraviolet performance.

[0015] 2. When the cable is heated, the cable reel is sleeved on the sliding pipe, and through the anti-pull assembly, the support rail slides, so that the telescopic column drives the tensioning block to slide, fixes the cable reel, and at the same time makes the rotating pipe, the sliding pipe and the cable reel rotate in the reverse direction, winds and straightens the cable, ensures that the cable is located on the support table, and also avoids the phenomenon of the cable being loose and interfering during the descent of the furnace body.

[0016] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not intended to limit the present disclosure.

[0017] This application document provides an overview of various implementations or examples of the technologies described in this disclosure, and is not a complete disclosure of the entire scope or all features of the disclosed technologies. Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments recorded in this invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings.

[0019] Figure 1 Schematic diagram of the cable main body structure provided by an embodiment of the present invention; Figure 2 Schematic diagram of the overall structure of the preparation device provided by an embodiment of the present invention; Figure 3 Cross-sectional view of the column and the rotating tube provided by an embodiment of the present invention; Figure 4 Provided by an embodiment of the present invention Figure 3 Enlarged view of part A in Figure 5 Provided by an embodiment of the present invention Figure 3 Enlarged view of part B in Figure 6 Schematic diagram of the support track and the reciprocating tube structure provided by an embodiment of the present invention; Figure 7 Schematic diagram of the reversing tube and the arc-shaped plate structure provided by an embodiment of the present invention; Figure 8 Cross-sectional view of the reversing tube provided by an embodiment of the present invention.

[0020] Description of the reference numerals: 1. Tinned conductor; 11. Water-blocking glue; 12. Insulating layer; 13. Water-blocking tape; 14. Sheath layer; 15. Connecting rib; 2. Base; 21. Furnace body; 22. Support table; 23. Support rod; 24. Traction wheel; 25. Fixed groove; 3. Column; 31. Rotating part; 4. Rotating tube; 41. Support track; 42. Slide block; 43. Guide groove; 5. Sliding tube; 51. Telescopic column; 52. Tensioning block; 53. First spring; 54. Ball; 55. Friction plate; 6. Reciprocating tube; 61. Push rod; 62. Guide post; 63. Convex block; 7. Reversing tube; 71. Arc-shaped plate; 72. First inclined part; 73. Second inclined part; 74. Second spring; 8. Cable reel. Detailed Description of the Embodiments

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present disclosure. Apparently, the described embodiments are some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present disclosure without creative efforts shall fall within the scope of protection of the present disclosure.

[0022] Please refer to FIGS. 1-8. A double-core water-blocking and weather-resistant photovoltaic DC cable includes two cable bodies. From the inside to the outside of the cable body, there are a tinned conductor 1, a water-blocking glue 11, an insulating layer 12, a water-blocking tape 13, and a sheath layer 14 in sequence; a connecting rib 15 is fixedly arranged between the two cable bodies; the water-blocking tape 13 is double-layered and wound around the insulating layer 12, and the double-layer water-blocking tapes 13 are made of PET substrate and acrylic glue respectively; the insulating layer 12 is double-layered, the inner layer is XLPE added with 3% nano-aluminum hydroxide, and the outer layer is XLPE added with 5% nano-carbon black. By coating a hot-melt water-blocking glue 11 with a thickness of 0.1-0.3 mm, a melting point of ≥125°C, and a water swelling rate of ≥300% between the tinned conductor 1 and the insulating layer 12 for longitudinal water blocking, and by setting the double-layer water-blocking tape 13 and making it of PET substrate and acrylic glue respectively for radial water blocking, the water-blocking performance is effectively improved. The inner layer of the insulating layer 12 is XLPE added with 3% nano-aluminum hydroxide, which effectively improves the flame retardancy, and the outer layer is XLPE added with 5% nano-carbon black for anti-ultraviolet and water-blocking resistance, improving its water-blocking and anti-ultraviolet performance.

[0023] A method for preparing a double-core water-blocking and weather-resistant photovoltaic DC cable, which is used to prepare the above-mentioned double-core water-blocking and weather-resistant photovoltaic DC cable, includes a base 2, a furnace body 21 and a support table 22. A column 3 is fixedly arranged on the base 2, a rotating tube 4 is rotatably arranged on the column 3, a sliding tube 5 is sleeved outside the rotating tube 4. When the cable reel 8 relaxes the cable, as the rotating tube 4 rotates, the sliding tube 5 slides; a plurality of telescopic columns 51 are slidably arranged on the sliding tube 5, a tensioning block 52 is fixedly arranged on the telescopic column 51, and the tensioning block 52 abuts against the cable reel 8. A support track 41 is slidably arranged on the rotating tube 4, a ball 54 is rotatably arranged on the telescopic column 51, and the ball 54 is rotatably arranged in the support track 41; a friction plate 55 is fixedly arranged on the telescopic column 51, and the friction plate 55 is in frictional contact with the rotating tube 4; it further includes a reverse pulling assembly, which is used to reverse the rotation of the rotating tube 4 when the tensioning block 52 abuts against the cable reel 8 to straighten the cable. When the cable reel 8 is fixed, the support track 41 slides, the telescopic column 51 slides, and the tensioning block 52 abuts against the cable reel 8 to complete the fixing of the cable reel 8. At the same time, the telescopic column 51 slides, so that the friction plate 55 is separated from the rotating tube 4. During the process of the cable reel 8 rotating and relaxing the cable, under the action of the ball 54 and the support track 41, when the cable reel 8 and the sliding tube 5 rotate, they can slide, so that the feeding position of the cable is directly opposite to the space between the furnace body 21 and the support table 22, improving the heating effect of the cable and also preventing the cable from contacting the furnace body 21; the friction plate 55 is in frictional contact with the rotating tube 4, so that when the cable reel 8 is installed, the sliding tube 5 remains stable and does not slide on the rotating tube 4, improving the installation portability of the cable reel 8.

[0024] In the further embodiment provided by the present invention, a first spring 53 is arranged between the telescopic column 51 and the sliding tube 5. The two ends of the first spring 53 are respectively fixedly connected to the telescopic column 51 and the sliding tube 5. The sliding tube 5 is sleeved outside the rotating tube 4, and the ball 54 on the telescopic column 51 is arranged in the support track 41. Under the action of the first spring 53, the sliding tube 5 is kept stable. After the tensioning block 52 fixes the cable reel 8, the first spring 53 is compressed.

[0025] Furthermore, a reciprocating tube 6 is slidably arranged on the column 3, a push rod 61 is rotatably arranged on the reciprocating tube 6, a guide post 62 is fixedly arranged on the push rod 61, a slider 42 is fixedly arranged on the support track 41, and a guide groove 43 is arranged on the slider 42. The guide post 62 is slidably arranged in the guide groove 43; the guide groove 43 includes a straight part and an inclined part. When the reciprocating tube 6 drives the push rod 61 to slide, through the cooperation of the guide post 62 and the inclined part of the guide groove 43, the slider 42 drives the support track 41 to slide to complete the abutment of the tensioning block 52 against the cable reel 8. And after the cable reel 8 is fixed, under the action of the straight part of the guide groove 43, it does not affect the sliding of the reciprocating tube 6.

[0026] Furthermore, a reverse tube 7 is fixedly arranged on the rotating tube 4, an arc-shaped plate 71 is slidably arranged on the reverse tube 7, a first inclined portion 72 is arranged on the arc-shaped plate 71, a convex block 63 is fixedly arranged on the reciprocating tube 6, and the convex block 63 is slidably arranged between the first inclined portion 72 and the reverse tube 7. When the reciprocating tube 6 slides, through the abutment of the convex block 63 and the first inclined portion 72 on the arc-shaped plate 71, the reverse tube 7 drives the rotating tube 4, the sliding tube 5 and the cable reel 8 to rotate in the reverse direction, straightening the cable, and avoiding contact between the furnace body 21 and the cable during the descending process due to the slack of the cable. Moreover, after the cable is straightened, the reciprocating tube 6 continues to slide, and the convex block 63 makes the arc-shaped plate 71 slide through the abutment on the first inclined portion 72, so that the reciprocating tube 6 continues to slide. After the reciprocating tube 6 finishes sliding, the convex block 63 is not in contact with the arc-shaped plate 71 and the reverse tube 7. At this time, the convex block 63 does not affect the rotation of the rotating tube 4.

[0027] In an embodiment further provided by the present invention, a second inclined portion 73 is arranged on the arc-shaped plate 71, and an inclined surface adapted to the second inclined portion 73 is arranged on the reverse tube 7. When the cable reel 8 is removed, the reciprocating tube 6 slides back to its original position. During this process, the convex block 63 Figure 7 abuts against the inclined surface (the dotted line part in

[0028] ) on the reverse tube 7 and the second inclined portion 73, causing the reverse tube 7 to rotate, so that no matter at what angle the reverse tube 7 stops rotating with the cable reel 8, it does not interfere with the reset sliding of the reciprocating tube 6.

[0029] Specifically, a rotating member 31 is rotatably arranged on the column 3, and the rotating member 31 is threadedly connected to the reciprocating tube 6. By rotating the rotating member 31, the sliding and resetting of the reciprocating tube 6 are controlled.

[0030] In a further solution provided by the present invention, support rods 23 are fixedly arranged on both sides of the base 2. Traction wheels 24 are rotatably arranged on the support rods 23. A fixing groove 25 is arranged on one of the support rods 23. The cable is placed on the traction wheels 24, so that the cable is more stable when being heated between the furnace body 21 and the support table 22. Moreover, when the cable is straightened, one end of the cable is placed in the fixing groove 25 from above the fixing groove 25. Since the fixing groove 25 is arranged on one side of the traction wheel 24, the cable will not be separated from the fixing groove 25 when being straightened. In this way, it is more convenient to fix one end of the cable and to straighten the cable.

[0031] In the present invention, the furnace body 21, the support table 22, the cable reel 8, the traction mode of the cable during the heating process, and the hydraulic device for controlling the lifting of the furnace body 21 are all prior arts. Their specific implementation manners and the achieved technical effects are common knowledge and conventional technical means in the art, and will not be elaborated in detail.

[0032] Working principle: When heating the cable, place the cable reel 8 on the sliding tube 5, extend a section of the cable, lay it on the two traction wheels 24 and the support platform 22, and clamp one end of the cable in the fixed slot 25. Subsequently, rotate the rotating member 31 to make the reciprocating tube 6 and the push rod 61 slide. During the sliding process, through the cooperation of the guide post 62 and the inclined portion on the guide groove 43, the support track 41 slides, and the telescopic column 51 is pushed to slide, so that the tensioning block 52 on the telescopic column 51 abuts against the cable reel 8 to fix the cable reel 8. At the same time, the friction plate 55 on the telescopic column 51 is disengaged from the rotating tube 4, and the fixation of the cable reel 8 can be completed. At the same time, when the reciprocating tube 6 slides, it drives the convex block 63 to slide. The convex block 63 abuts against the first inclined portion 72 on the arc plate 71, and the arc plate 71 drives the reverse rotating tube 7 and the rotating tube 4 to rotate, so that the cable reel 8 rotates in the reverse direction and winds the cable. Since one end of the cable is clamped in the fixed slot 25, after the cable is straightened, the rotating tube 4 and the cable reel 8 cannot rotate. At this time, the reciprocating tube 6 continues to slide with the convex block 63. During the sliding process, by squeezing the first inclined portion 72, the arc plate 71 slides and squeezes the second spring 74, so that the reciprocating tube 6 continues to slide. After the reciprocating tube 6 slides to the maximum value, the convex block 63 passes over the arc plate 71 and does not contact the reverse rotating tube 7. At this time, the furnace body 21 is lowered to the position of the support platform 22 through the hydraulic device, and one end of the cable located in the fixed slot 25 is taken out. Subsequently, the cable can be towed so that the cable passes through the furnace body 21 for heating. During this process, because the cable is towed, the cable reel 8 relaxes the cable and drives the rotating tube 4 and the sliding tube 5 to rotate by itself. During the rotation process, the sliding tube 5 slides on the rotating tube 4 through the action of the ball 54 on the telescopic column 51 and the support track 41, so that when the cable reel 8 relaxes the cable, the cable relaxation position is directly opposite to the heating positions of the traction wheel 24 and the furnace body 21. Moreover, the reciprocating tube 6 slides with the convex block 63 to a position where it is disengaged from the reverse rotating tube 7. When the rotating tube 4 drives the reverse rotating tube 7 to rotate, it will not affect the reciprocating tube 6 and the convex block 63.

[0033] Only some exemplary embodiments of the present invention have been described by way of illustration. Undoubtedly, for those of ordinary skill in the art, the described embodiments can be modified in various different 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 protection scope of the claims of the present invention.

Claims

1. A two-core water-blocking and weather-resistant photovoltaic DC cable, comprising two cable bodies, characterized in that, The cable body from the inside to the outside sequentially includes a tinned conductor (1), a water-blocking glue (11), an insulating layer (12), a water-blocking tape (13), and a sheath layer (14); A connecting rib (15) is fixedly arranged between the two sheath layers (14); The water-blocking tape (13) is double-layered and wound around the insulating layer (12), and the double-layer water-blocking tapes (13) are respectively made of a PET substrate and an acrylic glue; The insulating layer (12) is double-layered, the inner layer is XLPE added with 3% nano-aluminum hydroxide, and the outer layer is XLPE added with 5% nano-carbon black.

2. A preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable, which is used to prepare the double-core water-blocking and weather-resistant photovoltaic DC cable as described in claim 1, including a base (2), a furnace body (21) and a support table (22), characterized in that, A column (3) is fixedly arranged on the base (2), a rotating tube (4) is rotatably arranged on the column (3), a sliding tube (5) is sleeved outside the rotating tube (4), and when the cable reel (8) relaxes the cable, the sliding tube (5) slides as the rotating tube (4) rotates; A plurality of telescopic columns (51) are slidably arranged on the sliding tube (5), a tensioning block (52) is fixedly arranged on the telescopic column (51), the tensioning block (52) abuts against the cable reel (8), a support track (41) is slidably arranged on the rotating tube (4), a ball (54) is rotatably arranged on the telescopic column (51), and the ball (54) is rotatably arranged in the support track (41); A friction plate (55) is fixedly arranged on the telescopic column (51), and the friction plate (55) is in frictional contact with the rotating tube (4); It further includes a back-pulling assembly, which is used to reversely rotate the rotating tube (4) when the tensioning block (52) abuts against the cable reel (8) to straighten the cable.

3. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 2, wherein, A first spring (53) is arranged between the telescopic column (51) and the sliding tube (5), and the two ends of the first spring (53) are respectively fixedly connected to the telescopic column (51) and the sliding tube (5).

4. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 2, wherein, A reciprocating tube (6) is slidably arranged on the column (3), a push rod (61) is rotatably arranged on the reciprocating tube (6), a guiding column (62) is fixedly arranged on the push rod (61), a slider (42) is fixedly arranged on the support track (41), a guiding groove (43) is arranged on the slider (42), and the guiding column (62) is slidably arranged in the guiding groove (43); The guiding groove (43) includes a straight part and an inclined part.

5. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 4, characterized in that, The back-pulling assembly includes a reversing tube (7) fixedly arranged on the rotating tube (4), an arc-shaped plate (71) is slidably arranged on the reversing tube (7), a first inclined part (72) is arranged on the arc-shaped plate (71), a convex block (63) is fixedly arranged on the reciprocating tube (6), and the convex block (63) is slidably arranged between the first inclined part (72) and the reversing tube (7).

6. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 5, characterized in that, A second inclined part (73) is arranged on the arc-shaped plate (71), and an inclined surface adapted to the second inclined part (73) is arranged on the reversing tube (7).

7. A dual-core water-blocking and weather-resistant photovoltaic DC cable and a preparation method thereof according to claim 5, characterized in that, A second spring (74) is arranged between the arc-shaped plate (71) and the reversing tube (7), and the two ends of the second spring (74) are respectively fixedly connected to the arc-shaped plate (71) and the reversing tube (7).

8. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 4, characterized in that, A rotating part (31) is rotatably arranged on the column (3), and the rotating part (31) is threadedly connected to the reciprocating tube (6).

9. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 2, characterized in that, Support rods (23) are fixedly arranged on both sides of the base (2), and a traction wheel (24) is rotatably arranged on the support rod (23).

10. The preparation method of a double-core water-blocking and weather-resistant photovoltaic DC cable according to claim 9, characterized in that, A fixing groove (25) is arranged on one of the support rods (23).

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