A photovoltaic cable

Abstract

The utility model belongs to cable field especially relates to a kind of photovoltaic cable. Including two conductors, the conductor is spaced apart, the conductor is wrapped with inner sheath layer, the inner sheath layer is wrapped with flame-retardant layer, the flame-retardant layer is wrapped with hydrophobic layer, the hydrophobic layer is wrapped with braided layer, the braided layer is wrapped with reinforcing layer, the reinforcing layer of two conductors is wrapped with outer sheath layer, the outer sheath layer is wrapped together with two conductors, the utility model is improved to the structure of existing cylindrical cable, the setting of connecting portion makes the contact part of photovoltaic cable and fixed object only be connecting portion, further avoid the cable damage caused by abrasion, simultaneously, also avoid the heat dissipation problem caused by the thickness of insulating layer being too high, in addition, the material of outer sheath layer is improved and the setting of reinforcing belt, improve its wear resistance, ensure its service life.

Description

Technical Field

[0001] This utility model belongs to the field of cables, and in particular relates to a photovoltaic cable. Background Technology

[0002] With the deepening of my country's "dual carbon" goals and the increasing construction of solar photovoltaic power generation system facilities, the usage of cables is constantly increasing. Photovoltaic cables refer to the connecting cables between the battery and the inverter on the DC side of the photovoltaic power generation system (the part between the photovoltaic cells and the inverter terminals), and the connecting cables between the battery array and the controller or DC junction box.

[0003] Currently, photovoltaic cables are generally laid outdoors along with the design of photovoltaic power generation systems and the layout of photovoltaic panels. They are subject to long-term exposure to sunlight, temperature changes, and adverse weather conditions, which can damage the cables, reducing their insulation and service life.

[0004] Meanwhile, after the cable is laid and put into use, it is in a state of continuous power supply. During the power supply process, heat is constantly generated. If the heat dissipation thickness of the insulation layer exceeds the standard, the heat will be difficult to dissipate, and the performance of the cable will be affected, which will affect the normal use of the cable.

[0005] In addition, existing photovoltaic cables are mostly used for a long time in unshaded and sparsely populated areas, and need to be subjected to wind and sand abrasion over a long period of time. At the same time, the action of wind and sand will also cause friction between the photovoltaic cables and the fixed objects they are used for, resulting in cable damage. Utility Model Content

[0006] This invention addresses the technical problems existing in current photovoltaic cables by proposing a photovoltaic cable that is reasonably designed, simple in structure, easy to process, and can effectively improve the wear resistance of photovoltaic cables.

[0007] To achieve the above objectives, the technical solution adopted by this utility model is as follows: This utility model provides a photovoltaic cable, comprising two conductors spaced apart. Each conductor is covered by an inner sheath layer, the inner sheath layer is covered by a flame-retardant layer, the flame-retardant layer is covered by a hydrophobic layer, the hydrophobic layer is covered by a braided layer, the braided layer is covered by a reinforcing layer, and the reinforcing layers of the two conductors are covered by an outer sheath layer. The outer sheath layer wraps the two conductors together. The outer sheath layer includes a wrapping portion wrapped around the reinforcing layers of the two conductors and a connecting portion disposed between the two wrapping portions. A reinforcing band is disposed inside the connecting portion. The outer sheath layer is made of nylon and polyolefin materials co-extruded in two colors.

[0008] Preferably, the bottom of the connector is provided with an extension protrusion that extends below the conductor.

[0009] Preferably, the connecting part is also provided with only mounting through holes, which are spaced apart along the axial direction of the photovoltaic cable.

[0010] Preferably, the inner sheath layer is made of irradiated cross-linked polyolefin.

[0011] Preferably, the flame-retardant layer is made of talc.

[0012] Preferably, the hydrophobic layer is made of thermoplastic elastomer.

[0013] Preferably, the braided layer is made of silver fiber and glass fiber.

[0014] Preferably, both the reinforcing layer and the reinforcing strip are made of PP prepreg tape.

[0015] Preferably, the outer sheath layer is irradiated using a high-frequency, high-voltage electron accelerator.

[0016] Compared with the prior art, the advantages and positive effects of this utility model are as follows: This utility model provides a photovoltaic cable. By improving the structure of existing cylindrical cables, the connection part is designed so that the contact part between the photovoltaic cable and the fixed object is only the connection part, thereby avoiding cable damage caused by wear. At the same time, it also avoids heat dissipation problems caused by excessive insulation layer thickness. In addition, by improving the material of the outer sheath layer and adding reinforcing strips, its wear resistance is improved, ensuring its service life. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the photovoltaic cable provided in Example 1; Figure 2 A cross-sectional view of the photovoltaic cable provided in Example 1; In the above figures, 1 is the conductor; 2 is the inner sheath layer; 3 is the flame retardant layer; 4 is the hydrophobic layer; 5 is the braided layer; 6 is the reinforcing layer; 7 is the outer sheath layer; 71 is the wrapping part; 72 is the connecting part; 721 is the extension protrusion; 73 is the reinforcing strip; and 74 is the mounting through hole. Detailed Implementation

[0019] To better understand the above-mentioned objectives, features, and advantages of this utility model, the present utility model will be further described below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed in the following specification.

[0021] Example 1, as Figure 1 , Figure 2 As shown, this embodiment aims to provide a photovoltaic cable that meets the requirements of windy and sandy environments. Existing photovoltaic cables mainly have 2 cores, and only in the collection area of ​​centralized photovoltaic power stations are 4-core or 6-core structures used. Therefore, in this embodiment, a 2-core photovoltaic cable is used as an example. In addition, the structure provided in this embodiment is also the optimal 2-core solution.

[0022] Therefore, the photovoltaic cable provided in this embodiment includes two conductors. In this embodiment, the conductors are made of multiple wires twisted together, and the two conductors are spaced apart. The distance between them is sufficient to ensure that the width of the connection part after forming is about 1 cm.

[0023] To protect the conductor, an inner sheath is wrapped around it. In this embodiment, the inner sheath is made of irradiated cross-linked polyolefin. Irradiated cross-linked polyolefin has a temperature resistance of up to 125°C, which can withstand the conductor heating during photovoltaic cable operation for a long time, preventing the inner sheath from softening and deforming due to high temperatures. Furthermore, the cross-linked structure makes the molecules more tightly packed, resulting in high dielectric strength (≥20kV / mm) and low dielectric loss (tanδ≤0.001), which helps the insulation layer maintain stable electrical performance and reduces the risk of electric field distortion and partial discharge.

[0024] Considering the possibility of combustion, in this embodiment, a flame-retardant layer is wrapped around the inner sheath layer. In this embodiment, the flame-retardant layer is made of talc. In addition to being flame-retardant, talc can also improve processing fluidity. The flake structure of talc can reduce the internal friction of the hydrophobic layer, making the hydrophobic layer smoother during extrusion molding, avoiding defects such as bubbles and coke particles, and improving production efficiency and finished product qualification rate.

[0025] Considering outdoor use, a hydrophobic layer is wrapped around the flame-retardant layer. The thermoplastic elastomer of the hydrophobic layer, in this embodiment, is of the TPE type, which has excellent flexibility and fatigue resistance. It has rubber-like elasticity at room temperature and does not become brittle at low temperature (-40℃). It can easily adapt to the complex routing and frequent bending of cables, reduce the stretching and bending damage during laying, and is not prone to fatigue cracking after long-term use.

[0026] Considering the potential magnetic field issues associated with outdoor use, a braided layer is wrapped around the hydrophobic layer. This braided layer is made of silver and glass fibers, which helps prevent interference from external magnetic fields on the cable signal. This allows the photovoltaic cable to avoid internal and external interference, giving it strong anti-interference capabilities. The braided structure also helps improve the overall strength of the cable.

[0027] Considering outdoor use, strength is also a core requirement for photovoltaic cables. Therefore, a reinforcing layer is wrapped around the braided layer. Both the reinforcing layer and the reinforcing tape are made of PP prepreg tape. With fiber-reinforced PP prepreg tape as the core, the tensile strength and impact resistance are increased by 40%-60% compared to traditional wrapping materials. This effectively resists friction and compression during cable laying, preventing damage to the insulation layer. It also resists the gnawing of outdoor rodents or termites, ensuring the lifespan of the photovoltaic cable.

[0028] To secure the PP prepreg tape and ensure weather resistance, temperature resistance, and aging resistance, an outer sheath is wrapped around the reinforcing layers of the two conductors. Specifically, the outer sheath includes a wrapping portion surrounding the reinforcing layers and a connecting portion between the two wrapping portions. The connecting portion serves two purposes: connecting the two conductors and preventing the wrapping portion from contacting any fixed object. To this end, an extending protrusion is provided at the bottom of the connecting portion, extending below the conductor. This prevents the wrapping portion from contacting the fixed object and thus avoids wear, thereby increasing the cable's lifespan. The connection portion is also easy to secure with a close fit, reducing friction. It can be secured using adhesive or screws. For this purpose, mounting through holes are also provided on the connecting portion, spaced apart along the axial direction of the photovoltaic cable.

[0029] To enhance the connection, a reinforcing strip is provided within the connection, positioned near the bottom of the connection. This reinforcing strip is also made of pre-impregnated PP, effectively improving the strength of the connection. In this embodiment, to further enhance the strength of the outer sheath layer, it is co-extruded from nylon and polyolefin materials in two colors. Co-extrusion allows the nylon and polyolefin materials to fuse, addressing the non-flame-retardant nature of nylon and leveraging its impact resistance, abrasion resistance, and tear resistance to improve its strength. In this embodiment, to further enhance strength, the outer sheath layer undergoes irradiation treatment using a high-frequency, high-voltage electron accelerator. Irradiation treatment causes the material molecules to form a three-dimensional network structure, increasing tensile strength, tear resistance, and abrasion resistance by 30%-50%, making it less prone to deformation or breakage.

[0030] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments for application in other fields. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present utility model without departing from the technical solution of the present utility model shall still fall within the protection scope of the technical solution of the present utility model.

Claims

1. A photovoltaic cable comprising two conductors, characterized in that, The conductors are spaced apart, each conductor is wrapped with an inner sheath, the inner sheath is wrapped with a flame-retardant layer, the flame-retardant layer is wrapped with a hydrophobic layer, the hydrophobic layer is wrapped with a braided layer, the braided layer is wrapped with a reinforcing layer, the reinforcing layers of the two conductors are wrapped with an outer sheath, the outer sheath wraps the two conductors together, the outer sheath includes a wrapping part wrapped around the reinforcing layers of the two conductors and a connecting part disposed between the two wrapping parts, the connecting part is provided with a reinforcing band, and the outer sheath is made of nylon and polyolefin materials co-extruded in two colors.

2. A photovoltaic cable according to claim 1, characterized in that, The bottom of the connector is provided with an extension protrusion that extends to the underside of the conductor.

3. A photovoltaic cable according to claim 2, characterized in that, The connecting part is also provided with only mounting through holes, which are spaced apart along the axial direction of the photovoltaic cable.

4. A photovoltaic cable according to claim 1, characterized in that, The inner sheath layer is made of irradiated cross-linked polyolefin.

5. A photovoltaic cable according to claim 1, characterized in that, The flame-retardant layer is made of talc.

6. A photovoltaic cable according to claim 1, characterized in that, The hydrophobic layer is made of thermoplastic elastomer.

7. A photovoltaic cable according to claim 1, characterized in that, The woven layer is made of silver fiber and glass fiber.

8. A photovoltaic cable according to claim 1, characterized in that, Both the reinforcing layer and the reinforcing strip are made of PP prepreg tape.

9. A photovoltaic cable according to claim 1, characterized in that, The outer sheath layer is irradiated using a high-frequency, high-voltage electron accelerator.

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