Medium-voltage cable for photovoltaic power generation

Abstract

The invention relates to the technical field of cables, in particular to a medium-voltage cable for photovoltaic power generation, and solves the problems that an internal cable core of the medium-voltage cable is in a linear state, when the cable is subjected to an axial force, the cable core of the cable is broken or damaged due to poor axial elasticity, and after the medium-voltage cable is subjected to external pressure, the cable core of the cable is broken or damaged due to the axial force. And the internal cable core is easy to bend and damage or fracture. The medium-voltage cable for photovoltaic power generation comprises an insulating outer sheath, the inner side of the insulating outer sheath is provided with a pressure-resistant protective sleeve, the inner side of the pressure-resistant protective sleeve is provided with an armored protective sleeve, the inner side of the armored protective sleeve is provided with an insulating shielding protective sleeve, and a plurality of cable cores are inserted into the inner side of the insulating shielding protective sleeve. According to the invention, the cable core is bent in a wave shape through the cable core bundling structure, so that the cable core can be extended after being axially stressed, thereby preventing the cable core from being damaged or broken due to the fact that the cable core cannot be extended in the axial direction when the cable core is axially stressed.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and specifically to a medium-voltage cable for photovoltaic power generation. Background Art

[0002] A cable is made of one or more mutually insulated conductors and an outer insulating protective layer, and is a wire for transmitting electricity or information from one place to another. It is usually a rope-like structure formed by stranding several or several groups of wires (at least two wires in each group). The wires in each group are insulated from each other and are often twisted around a central wire. The whole is wrapped with a highly insulating covering layer. The cable has the characteristics of conducting electricity inside and being insulated outside. A medium-voltage cable is a power cable with a rated voltage between 1 kV and 35 kV (or 6 kV and 35 kV), which is used for power transmission and distribution at medium voltage levels and is a key link connecting substations and distribution networks. Medium-voltage cables are also commonly used for power transmission in photovoltaic power generation.

[0003] However, the cable core inside the medium-voltage cable is in a straight state. When the cable is subjected to an axial force, the cable core may break or be damaged due to the axial force because of its poor axial elasticity. Moreover, when the medium-voltage cable is subjected to an external pressure, the internal cable core is prone to bending and being damaged or broken. Therefore, it does not meet the existing requirements. For this reason, we propose a medium-voltage cable for photovoltaic power generation. Summary of the Invention

[0004] The purpose of the present invention is to provide a medium-voltage cable for photovoltaic power generation to solve the problems mentioned in the above background art, such as the cable core inside the medium-voltage cable being in a straight state. When the cable is subjected to an axial force, the cable core may break or be damaged due to the axial force because of its poor axial elasticity. Moreover, when the medium-voltage cable is subjected to an external pressure, the internal cable core is prone to bending and being damaged or broken.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A medium-voltage cable for photovoltaic power generation includes an insulating outer skin. Inside the insulating outer skin, there is a compression protection sleeve. Inside the compression protection sleeve, there is an armored protection sleeve. Inside the armored protection sleeve, there is an insulating shielding protection sleeve. Inside the insulating shielding protection sleeve, a plurality of cable cores are inserted. At both ends inside the insulating shielding protection sleeve, there are sealing filling blocks. Between the two sealing filling blocks, there is a cable core bundling structure, and the ends of the cable cores penetrate through the sealing filling blocks. The cable core bundling structure includes a plurality of first guiding rings and a plurality of second guiding rings. A rubber connecting strip is fixed between the first guiding ring and the plurality of second guiding rings. A central adjusting flexible rod is axially inserted through the first guiding ring and the second guiding ring. The first guiding ring and the second guiding ring are distributed at intervals. Six support short rods are fixedly arranged on the outer surface of the first guiding ring in a circular array. A bundling support ring is fixed on the outer sides of the six support short rods. A plurality of cable core first bundling holes are arranged through the surface of the bundling support ring in a circular array around its center. A plurality of sliding connecting rods are slidably installed through the interior of the second guiding ring. The number of the sliding connecting rods is the same as the number of the cable core first bundling holes. An adjusting ring is fixed at the outer end of the sliding connecting rod. A cable core second bundling hole is axially arranged through the adjusting ring. The cable core of the cable passes through the inner sides of the cable core second bundling hole and the cable core first bundling hole.

[0006] Preferably, the adjusting ring corresponds to the cable core first bundling hole in position. The end of the central adjusting flexible rod passes through a sealing filling block. A plurality of receiving holes are arranged inside the second guiding ring in a circular array around its axis. One end of the sliding connecting rod is slidably inserted into the receiving hole and points to the axis of the second guiding ring. An adjusting ball head is fixed at the end of the sliding connecting rod located inside the second guiding ring. The adjusting ball head is hemispherical.

[0007] Preferably, elastic bundling ropes are arranged on both sides of the outer end of the sliding connecting rod. The two ends of the elastic bundling rope are respectively fixedly connected with the outer surface of the adjusting ring and the outer surface of the second guiding ring.

[0008] Preferably, a plurality of adjusting grooves are arranged on the outer surface of the central adjusting flexible rod in a circular array. Connecting arc surfaces are arranged on both sides of the adjusting groove.

[0009] Preferably, the compressive protection sleeve includes a rubber outer sleeve. The rubber outer sleeve is located between the insulating outer skin and the insulating shielding protection sleeve and is completely attached to the inner surface of the insulating outer skin and the outer surface of the insulating shielding protection sleeve. A plurality of rubber connecting rings are arranged inside the rubber outer sleeve. The rubber connecting rings are linearly arrayed along the length direction of the rubber outer sleeve.

[0010] Preferably, a buffer ring and a rigid support ring are arranged between every two adjacent rubber connecting rings. The rigid support ring is located inside the buffer ring and the centers of the rigid support ring and the buffer ring coincide. The ends of the buffer ring and the rigid support ring are connected to the rubber connecting ring by an adhesive.

[0011] Preferably, a plurality of buffer air bags are arranged between the buffer ring and the rigid support ring. The buffer air bags are arranged in a circular array around the center of the rigid support ring.

[0012] Preferably, the inside of the buffer airbag is hollow and filled with inert gas, and the buffer airbag is fixedly bonded to the buffer ring and the rigid support ring through an adhesive.

[0013] Preferably, a plurality of first buffer elastic sheets are fixed on the inner surface of the buffer ring, and a plurality of second buffer elastic sheets are fixed on the outer surface of the buffer ring. The number of the first buffer elastic sheets and the second buffer elastic sheets is the same and they are distributed in a circular array around the center of the buffer ring. Both the first buffer elastic sheets and the second buffer elastic sheets are arc-shaped.

[0014] Preferably, rigid T-shaped support blocks are fixed on both sides of the buffer airbag, and the rigid T-shaped support blocks are located between the first buffer elastic sheets and the second buffer elastic sheets.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The cable core is bent in a wavy shape through the cable core bunching structure of the present invention, so that the cable core can be extended and elongated after being axially stressed, thereby avoiding damage or breakage of the cable core caused by the inability to extend axially when the cable core is axially stressed. 2. The present invention increases the offset, weakening and absorption of the external pressure on the cable through the compression protection sleeve, and uses the bunching support ring and the adjusting ring to bunch and support the cable core. At the same time, the bunching support ring and the adjusting ring can prevent the insulation shielding protection sleeve from directly contacting the cable core, thereby avoiding damage, breakage or fracture of the cable core caused by bending due to external pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic structural diagram of the whole of the present invention; Figure 2 is a schematic cross-sectional view of the cable of the present invention; Figure 3 is a schematic structural diagram of the cable core bunching structure of the present invention; Figure 4 is Figure 2 an enlarged structural view of part A in Figure 5 is a schematic structural diagram of the bunching support ring of the present invention; Figure 6 is a structural sectional view of the second guiding ring of the present invention; Figure 7 is a schematic structural diagram of the central adjusting soft rod of the present invention; Figure 8 is a schematic structural diagram of the compression protection sleeve of the present invention; Figure 9 is Figure 8 an enlarged structural view of part B in

[0017] In the figure: 1, insulating outer sheath; 2, armored protective sheath; 3, insulating shielding protective sheath; 4, cable core bundling structure; 401, central adjusting flexible rod; 402, bundling support ring; 403, adjusting ring; 404, first guiding ring; 405, second guiding ring; 406, supporting short rod; 407, first core bundling hole; 408, sliding connecting rod; 409, elastic bundling rope; 410, second core bundling hole; 411, adjusting groove; 412, receiving hole; 413, adjusting ball head; 414, connecting arc surface; 415, rubber connecting strip; 5, compressive protection sheath; 501, rubber outer sleeve; 502, rubber connecting ring; 503, buffer ring; 504, rigid support ring; 505, buffer airbag; 506, first buffer spring piece; 507, second buffer spring piece; 508, rigid T-shaped support block; 6, cable core; 7, sealing and filling block. Detailed implementation mode

[0018] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0019] As Figure 1 and Figure 2 shown, a medium-voltage cable for photovoltaic power generation includes an insulating outer sheath 1. A compressive protection sheath 5 is provided inside the insulating outer sheath 1. An armored protection sheath 2 is provided inside the compressive protection sheath 5. An insulating shielding protection sheath 3 is provided inside the armored protection sheath 2. A plurality of cable cores 6 are inserted inside the insulating shielding protection sheath 3. Sealing and filling blocks 7 are filled at both ends inside the insulating shielding protection sheath 3. A cable core bundling structure 4 is installed between the two sealing and filling blocks 7. The end of the cable core 6 penetrates through the sealing and filling block 7, and the sealing and filling block 7 is used to seal the end of the insulating shielding protection sheath 3 to prevent air or water vapor from entering the cable from the cable end.

[0020] As Figure 2 、 Figures 5 to 7As shown in the figure, the cable core bundling structure 4 includes a plurality of first guiding rings 404 and a plurality of second guiding rings 405. A rubber connecting strip 415 is fixed between the first guiding rings 404 and the plurality of second guiding rings 405. A central adjusting soft rod 401 is axially inserted through the first guiding rings 404 and the second guiding rings 405. The first guiding rings 404 and the second guiding rings 405 are distributed at intervals. Six support short rods 406 distributed in a circular array are fixed on the outer surface of the first guiding ring 404. A bundling support ring 402 is fixed on the outer sides of the six support short rods 406. A plurality of cable core first bundling holes 407 distributed in a circular array around its center are provided through the surface of the bundling support ring 402. A plurality of sliding connecting rods 408 are slidably installed through the inside of the second guiding ring 405. The number of the sliding connecting rods 408 is the same as the number of the cable core first bundling holes 407. An adjusting ring 403 is fixed at the outer end of the sliding connecting rod 408. A cable core second bundling hole 410 is axially provided through the adjusting ring 403. The cable core 6 passes through the inside of the cable core second bundling hole 410 and the cable core first bundling hole 407. The adjusting ring 403 and the bundling support ring 402 are used to guide and support the cable core 6, avoiding entanglement between adjacent cable cores 6. When the cable is squeezed, the bundling support ring 402 and the adjusting ring 403 isolate the cable core 6 from the insulating shielding protection sleeve 3, so as to ensure that the external pressure will not directly act on the cable core 6 and avoid breakage or damage of the cable core 6.

[0021] The positions of the adjusting ring 403 and the cable core first bundling holes 407 correspond one by one. The end of the central adjusting soft rod 401 passes through the sealing filling block 7. A plurality of receiving holes 412 distributed in a circular array around its axis are provided inside the second guiding ring 405. One end of the sliding connecting rod 408 is slidably inserted inside the receiving hole 412 and points to the axis of the second guiding ring 405. An adjusting ball head 413 is fixed at the end of the sliding connecting rod 408 located inside the second guiding ring 405. The adjusting ball head 413 is hemispherical. Elastic bundling ropes 409 are provided on both sides of the outer end of the sliding connecting rod 408. The two ends of the elastic bundling ropes 409 are respectively fixed to the outer surface of the adjusting ring 403 and the outer surface of the second guiding ring 405. The pulling force of the elastic bundling ropes 409 is used to make the adjusting ring 403 and the cable core 6 passing through the adjusting ring 403 approach the second guiding ring 405, so that the cable core 6 inserted inside the insulating shielding protection sleeve 3 is bent in a wavy shape. Thus, when the cable is axially stressed, the cable core 6 can extend along the cable axis, ensuring that the cable core 6 will not be pulled off due to the axial stress of the cable.

[0022] The outer surface of the central adjusting flexible rod 401 is provided with a plurality of adjusting grooves 411 distributed in a circular array. Both sides of the adjusting groove 411 are provided with connecting arc surfaces 414. When the central adjusting flexible rod 401 rotates and aligns with the receiving hole 412, the receiving hole 412 is received by the adjusting groove 411, so as to ensure that the adjusting ring 403 drives the cable core 6 to approach the second guiding ring 405 under the tension of the elastic binding rope 409, making the cable core 6 bend in a wavy shape. The connecting arc surface 414 makes the end of the adjusting groove 411 contact the outer surface of the central adjusting flexible rod 401 smoothly, ensuring that when the central adjusting flexible rod 401 rotates, the receiving hole 412 can be separated from the inner side of the adjusting groove 411 along the connecting arc surface 414, thereby changing the position of the adjusting ring 403 and making the axis of the second core receiving hole 410 coincide with the axis of the first core receiving hole 407.

[0023] As Figure 4 , Figure 8 and Figure 9 shown, the compression protection sleeve 5 includes a rubber outer sleeve 501. The rubber outer sleeve 501 is located between the insulating outer skin 1 and the insulating shielding protection sleeve 3 and is completely attached to the inner surface of the insulating outer skin 1 and the outer surface of the insulating shielding protection sleeve 3. A plurality of rubber connecting rings 502 are provided on the inner side of the rubber outer sleeve 501. The rubber connecting rings 502 are linearly arrayed along the length direction of the rubber outer sleeve 501. A buffer ring 503 and a rigid support ring 504 are provided between every two adjacent rubber connecting rings 502. The rigid support ring 504 is located inside the buffer ring 503 and the centers of the circles coincide. The ends of the buffer ring 503 and the rigid support ring 504 are connected to the rubber connecting ring 502 by an adhesive. The rubber connecting ring 502 is used to increase the extensibility of the whole compression protection sleeve 5 along the length direction, and the buffer ring 503 and the rigid support ring 504 are used to improve the compression resistance of the whole compression protection sleeve 5, playing a role in protecting the cable core 6.

[0024] A plurality of buffer air bags 505 are provided between the buffer ring 503 and the rigid support ring 504. The buffer air bags 505 are distributed in a circular array around the center of the rigid support ring 504. The inside of the buffer air bag 505 is hollow and filled with inert gas. The buffer air bags 505 are fixedly bonded to the buffer ring 503 and the rigid support ring 504 by an adhesive. The buffer air bags 505 are used to prevent the buffer ring 503 from approaching the buffer ring 503 direction when receiving external pressure, thereby weakening and offsetting the external pressure and reducing the pressure received by the rigid support ring 504, so as to reduce the deformation probability of the rigid support ring 504.

[0025] A plurality of first buffer elastic pieces 506 are fixed to the inner surface of the buffer ring 503, and a plurality of second buffer elastic pieces 507 are fixed to the outer surface of the buffer ring 503. The number of the first buffer elastic pieces 506 and the second buffer elastic pieces 507 is the same and they are distributed in a circular array around the center of the buffer ring 503. Both the first buffer elastic pieces 506 and the second buffer elastic pieces 507 are arc-shaped. Rigid T-shaped support blocks 508 are fixed to both sides of the buffer airbag 505. The rigid T-shaped support blocks 508 are located between the first buffer elastic pieces 506 and the second buffer elastic pieces 507. The elasticity between the buffer ring 503 and the rigid support ring 504 is increased by using the first buffer elastic pieces 506 and the second buffer elastic pieces 507, thereby improving the overall compressive performance of the compression protection sleeve 5. After the buffer airbag 505 is deformed under pressure, the rigid T-shaped support blocks 508 enter between the first buffer elastic pieces 506 and the second buffer elastic pieces 507 and contact the first buffer elastic pieces 506 and the second buffer elastic pieces 507. After the rigid T-shaped support blocks 508 are separated from the first buffer elastic pieces 506 and the second buffer elastic pieces 507, the mutual approach of the first buffer elastic pieces 506 and the second buffer elastic pieces 507 is blocked, so as to resist the external pressure.

[0026] Working principle: First, rotate the central adjustment soft rod 401. When the central adjustment soft rod 401 rotates, it squeezes the adjustment ball head 413 located inside the adjustment groove 411, so that the adjustment ball head 413 disengages from the inside of the adjustment groove 411 along the connecting arc surface 414. At this time, the adjustment ball head 413 enters the inside of the receiving hole 412, and the sliding connecting rod 408 extends out from the inside of the second guiding ring 405 and the elastic converging rope 409 is stretched. After the adjustment ball head 413 is completely immersed in the inside of the receiving hole 412, the axis of the adjustment ring 403 coincides with the axis of the cable core first converging hole 407. At this time, the staff passes the cable core 6 through the inside of the cable core second converging hole 410 and the cable core first converging hole 407. After the cable core 6 is installed, rotate the central adjustment soft rod 401 to align the adjustment groove 411 with the adjustment ball head 413 again. At this time, the elastic converging rope 409 restores elastically to drive the adjustment ring 403 and the sliding connecting rod 408 to restore. After the adjustment ring 403 is restored, the part of the cable core 6 passing through the cable core second converging hole 410 approaches the central adjustment soft rod 401. At this time, the cable core 6 is bent in a wavy shape. Then, the cable core converging structure 4 with the cable core 6 installed, the converging support ring 402 and the adjustment ring 403 are installed inside the insulation shielding protection sleeve 3, and the two ends of the insulation shielding protection sleeve 3 are sealed by using the sealing filling block 7. Then, the insulation shielding protection sleeve 3, the armor protection sleeve 2, the compression protection sleeve 5, and the insulation outer skin 1 are installed on the outside of the insulation shielding protection sleeve 3 in sequence to complete the assembly of the cable; When the cable is subjected to an axial tensile force, the cable will stretch along its length due to the axial tensile force. At this time, due to the adjusting ring 403 and the converging support ring 402, the cable core 6 inserted inside the insulating shield protective sleeve 3 is bent in a wavy shape. When the cable is axially stressed, the cable core 6 gradually tends to a straight line from the wavy state due to the axial tensile force. At this time, the adjusting ring 403 drives the sliding connecting rod 408 to slide out of the second guiding ring 405, and the elastic converging rope 409 is stretched. During this process, the cable core 6 can extend along the length direction of the cable, so as to ensure that when the cable is axially stressed, the cable core 6 offsets the axial tensile force by extending along the length direction of the cable, thereby avoiding damage or breakage of the cable core 6 due to axial stress. When the outside of the cable is subjected to pressure, the insulating outer skin 1 transfers the pressure to the rubber outer sleeve 501 and the buffer ring 503. After being compressed, the buffer ring 503 bends and deforms towards the rigid support ring 504, and the rigid support ring 504 drives the first buffer spring piece 506 to approach the second buffer spring piece 507. At the same time, the buffer airbag 505 is squeezed and deformed. After the buffer airbag 505 deforms, the end moves towards the first buffer spring piece 506 and the second buffer spring piece 507, so that the rigid T-shaped support block 508 enters between the first buffer spring piece 506 and the second buffer spring piece 507. At this time, the first buffer spring piece 506 squeezes the rigid T-shaped support block 508 on the second buffer spring piece 507. Since the rigid T-shaped support block 508 prevents the first buffer spring piece 506 and the second buffer spring piece 507 from contacting each other, at this time, the first buffer spring piece 506 and the second buffer spring piece 507 elastically deform, and the external pressure is offset and weakened through the elastic deformation of the buffer airbag 505, the first buffer spring piece 506, and the second buffer spring piece 507. At the same time, because the cable core 6 is supported by the adjusting ring 403 and the converging support ring 402, the external pressure will ultimately only act on the converging support ring 402 and the adjusting ring 403, and the cable core 6 will not be directly affected by the external pressure, thereby avoiding damage or breakage of the cable core 6 caused by the bending of the cable core 6 due to external pressure.

[0027] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

Claims

1. A medium-voltage cable for photovoltaic power generation, comprising an insulating outer sheath (1), characterized in that: An anti-pressure protection sleeve (5) is provided inside the insulating outer sheath (1). An armored protection sleeve (2) is provided inside the anti-pressure protection sleeve (5). An insulating shielding protection sleeve (3) is provided inside the armored protection sleeve (2). A plurality of cable cores (6) are inserted inside the insulating shielding protection sleeve (3). Sealing filling blocks (7) are filled inside both ends of the insulating shielding protection sleeve (3). A cable core bundling structure (4) is installed between the two sealing filling blocks (7). The ends of the cable cores (6) penetrate through the sealing filling blocks (7). The cable core bundling structure (4) includes a plurality of first guiding rings (404) and a plurality of second guiding rings (405). A rubber connecting strip (415) is fixed between the first guiding ring (404) and the plurality of second guiding rings (405). A central adjusting soft rod (401) is axially penetrated and inserted through the first guiding ring (404) and the second guiding ring (405). The first guiding ring (404) and the second guiding ring (405) are distributed at intervals. Six support short rods (406) distributed in a circular array are fixed on the outer surface of the first guiding ring (404). A bundling support ring (402) is fixed on the outer sides of the six support short rods (406). A plurality of cable core first bundling holes (407) distributed in a circular array around its center are penetrated through the surface of the bundling support ring (402). A plurality of sliding connecting rods (408) are installed inside the second guiding ring (405) through sliding. The number of the sliding connecting rods (408) is the same as the number of the cable core first bundling holes (407). An adjusting ring (403) is fixed at the outer end of the sliding connecting rod (408). A cable core second bundling hole (410) is axially penetrated through the adjusting ring (403). The cable cores (6) pass through the inside of the cable core second bundling hole (410) and the cable core first bundling hole (407).

2. The medium-voltage cable for photovoltaic power generation according to claim 1, wherein: The adjusting ring (403) corresponds to the cable core first bundling hole (407) in position. The end of the central adjusting soft rod (401) penetrates through the sealing filling block (7). A plurality of receiving holes (412) distributed in a circular array around its axis are provided inside the second guiding ring (405). One end of the sliding connecting rod (408) is slidably inserted inside the receiving hole (412) and points to the axis of the second guiding ring (405). An adjusting ball head (413) is fixed at the end of the sliding connecting rod (408) located inside the second guiding ring (405). The adjusting ball head (413) is hemispherical.

3. The medium-voltage cable for photovoltaic power generation according to claim 2, wherein: Elastic bundling ropes (409) are provided on both sides of the outer end of the sliding connecting rod (408). The two ends of the elastic bundling rope (409) are respectively fixed to the outer surface of the adjusting ring (403) and the outer surface of the second guiding ring (405).

4. The medium-voltage cable for photovoltaic power generation according to claim 3, characterized in that: A plurality of adjusting grooves (411) distributed in a circular array are provided on the outer surface of the central adjusting soft rod (401). Connecting arc surfaces (414) are provided on both sides of the adjusting groove (411).

5. The medium-voltage cable for photovoltaic power generation according to claim 1, wherein: The compression protection sleeve (5) includes a rubber outer sleeve (501). The rubber outer sleeve (501) is located between the insulating outer skin (1) and the insulating shield protection sleeve (3) and is in complete fit with the inner surface of the insulating outer skin (1) and the outer surface of the insulating shield protection sleeve (3). A plurality of rubber connecting rings (502) are provided on the inner side of the rubber outer sleeve (501), and the rubber connecting rings (502) are distributed in a linear array along the length direction of the rubber outer sleeve (501).

6. The medium-voltage cable for photovoltaic power generation according to claim 5, wherein: A buffer ring (503) and a rigid support ring (504) are provided between every two adjacent rubber connecting rings (502). The rigid support ring (504) is located inside the buffer ring (503) and the centers of the circles of the two coincide. The ends of the buffer ring (503) and the rigid support ring (504) are connected to the rubber connecting ring (502) by an adhesive.

7. The medium-voltage cable for photovoltaic power generation according to claim 6, wherein: A plurality of buffer air bags (505) are provided between the buffer ring (503) and the rigid support ring (504), and the buffer air bags (505) are distributed in a circular array around the center of the rigid support ring (504).

8. The medium-voltage cable for photovoltaic power generation according to claim 7, characterized in that: The inside of the buffer air bag (505) is hollow and filled with an inert gas, and the buffer air bag (505) is fixedly bonded to the buffer ring (503) and the rigid support ring (504) by an adhesive.

9. The medium-voltage cable for photovoltaic power generation according to claim 8, characterized in that: A plurality of first buffer spring pieces (506) are fixed on the inner surface of the buffer ring (503), and a plurality of second buffer spring pieces (507) are fixed on the outer surface of the buffer ring (503). The number of the first buffer spring pieces (506) and the second buffer spring pieces (507) is the same and they are distributed in a circular array around the center of the buffer ring (503). Both the first buffer spring pieces (506) and the second buffer spring pieces (507) are arc-shaped.

10. The medium-voltage cable for photovoltaic power generation according to claim 9, characterized in that: Rigid T-shaped support blocks (508) are fixed on both sides of the buffer air bag (505), and the rigid T-shaped support blocks (508) are located between the first buffer spring pieces (506) and the second buffer spring pieces (507).

Images