Waterproof tree crosslinked polyethylene insulation medium voltage dc cable

Abstract

The utility model belongs to waterproof cable application technical field, specifically disclose waterproof tree cross -linked polyethylene insulation medium -voltage direct current cable, including conductor core, inner shielding layer, inner filling layer, outer shielding layer, inner sheath, water -resisting filling layer, insulating layer and outer sheath, wherein, inner sheath, outer sheath are metal cover. The utility model has the beneficial effect that: be applicable to the area of high groundwater level or perennial rainy weather use, the protection design of inner sheath, outer sheath simultaneously, make overall structural strength big, can bear the soil pressure, water pressure and external force pressure from outside etc., guarantee the security of electric power transmission, inner filling layer, inner shielding layer, outer shielding layer and water -resisting filling layer, constitute double water -resisting structure and double structure shielding, make overall structure have good sealing, prevent water tree from producing and even electric field, prevent the function of partial discharge, improve the security and reliability of cable, guarantee the electrical performance of cable, prolong the service life of cable.

Description

Technical Field

[0001] This utility model belongs to the field of waterproof cable application technology, specifically relating to a waterproof cross-linked polyethylene insulated medium-voltage DC cable. Background Technology

[0002] Cables that can function normally in water are collectively referred to as water-blocking (waterproof) power cables. When cables are laid underwater, in places that are frequently submerged in water or damp, the cables are required to have water-proof (water-resistant) functions, that is, to have a complete water-blocking function, in order to prevent water from penetrating into the cable and causing damage to the cable, and to ensure the long-term stable operation of the cable underwater.

[0003] Cross-linked polyethylene (XLPE) insulated power cables have become the most widely used insulation material due to their excellent electrical and mechanical properties, simple manufacturing process, lightweight structure, large transmission capacity, convenient installation and maintenance, and lack of limitations caused by elevation differences. However, they are particularly sensitive to moisture. If water gets into the insulation during manufacturing and operation, it can easily cause water treeing breakdown, greatly shortening the cable's service life.

[0004] Current insulated cables, especially medium-voltage cross-linked polyethylene cables operating under DC voltage, need to have appropriate waterproof capabilities when used in water or humid environments.

[0005] Therefore, based on the above problems, this utility model provides a waterproof cross-linked polyethylene insulated medium-voltage DC cable. Utility Model Content

[0006] Purpose of the utility model: The purpose of this utility model is to provide a waterproof cross-linked polyethylene insulated medium-voltage DC cable, which solves the waterproof problem of current medium-voltage cross-linked polyethylene insulated cables in the background art, and at the same time has the characteristics of strong pressure bearing capacity, durability and high safety.

[0007] Technical Solution: The waterproof cross-linked polyethylene insulated medium-voltage DC cable provided by this utility model includes a conductor core, an inner shielding layer, an inner filling layer, an outer shielding layer, an inner sheath, a water-blocking filling layer, an insulation layer, and an outer sheath; the conductor core is provided with an inner shielding layer on its outer surface, the inner shielding layer is provided with an inner filling layer on its outer surface, the inner filling layer is provided with an outer shielding layer on its outer surface, the outer shielding layer is provided with an inner sheath on its outer surface, the inner sheath is provided with a water-blocking filling layer on its outer surface, the water-blocking filling layer is provided with an insulation layer on its outer surface, and the insulation layer is provided with an outer sheath on its outer surface; wherein, the inner sheath and the outer sheath are metal sheaths.

[0008] In this technical solution, the inner shielding layer is a copper wire braided mesh layer.

[0009] In this technical solution, the inner filling layer is a water-resistant rubber layer.

[0010] In this technical solution, the outer shielding layer is an aluminum foil layer.

[0011] In this technical solution, the water-blocking filling layer is a water-blocking paste, water-blocking powder, or water-blocking tape.

[0012] In this technical solution, the insulating layer is a cross-linked polyethylene insulating layer.

[0013] In this technical solution, the inner sheath and the outer sheath are either lead sheaths or aluminum sheaths, respectively; wherein, the thickness of the inner sheath is less than the thickness of the outer sheath.

[0014] In this technical solution, the thickness of the inner filling layer is greater than the thickness of the water-blocking filling layer.

[0015] Compared with existing technologies, the beneficial effects of this utility model of waterproof tree-resistant cross-linked polyethylene insulated medium-voltage DC cable are as follows: 1. It is suitable for use in areas with high groundwater levels or frequent rainfall. The protective design of the inner and outer sheaths enhances the overall structural strength, enabling it to withstand external soil pressure, water pressure, and other external forces, ensuring the safety of power transmission; 2. The inner filling layer, inner shielding layer, outer shielding layer, and water-blocking filling layer constitute a double water-blocking structure and a double structural shielding, giving the overall structure excellent sealing properties, preventing water tree formation, and providing a uniform electric field and preventing partial discharge. This improves the cable's safety and reliability, ensures its electrical performance, and extends its service life. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of the waterproof cross-linked polyethylene insulated medium-voltage DC cable of this utility model; The numbers in the diagram are as follows: 10-Conductor core, 100-Inner shielding layer, 101-Inner filling layer, 102-Outer shielding layer, 103-Inner sheath, 104-Water-blocking filling layer, 105-Insulation layer, 106-Outer sheath. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the protection scope of the present utility model.

[0019] In the description of this utility model, it should be noted that the terms "top," "bottom," "one side," "the other side," "front," "back," "middle part," "inner," "top," and "bottom," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. The terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. Furthermore, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "joined" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0020] Example like Figure 1 The waterproof cross-linked polyethylene insulated medium-voltage DC cable shown includes a conductor core 10, an inner shielding layer 100, an inner filling layer 101, an outer shielding layer 102, an inner sheath 103, a water-blocking filling layer 104, an insulation layer 105, and an outer sheath 106. The conductor core 10 is provided with an inner shielding layer 100 on its outer layer. The inner shielding layer 100 has an inner filling layer 101 on its outer layer. An outer shielding layer 102 is provided on the outer layer of the inner filling layer 101. The outer shielding layer 102 is provided with an inner sheath 103. The outer layer of the inner sheath 103 is provided with a water-resistant filling layer 104. An insulating layer 105 is provided on the outer layer of the water-blocking filling layer 104. The outer layer of the insulation layer 105 is provided with an outer sheath 106; wherein the inner sheath 103 and the outer sheath 106 are metal sleeves.

[0021] The working principle or structural principle is as follows: the inner shielding layer 100 and the outer shielding layer 102 provide a uniform electric field and prevent partial discharge for the overall cable structure, thus providing dual protection; the inner filling layer 101 and the water-blocking filling layer 104 provide a sealing and water tree prevention for the overall cable structure; the inner sheath 103 and the outer sheath 106 provide high pressure resistance for the overall cable structure; and the insulation layer 105 provides corresponding electrical insulation protection for the overall cable structure.

[0022] In addition, the inner shielding layer 100 is preferably a copper wire woven mesh layer, using tin-plated copper wire or aluminum alloy wire, which has good conductivity and electromagnetic shielding performance.

[0023] In addition, the inner filling layer 101 is preferably a water-blocking rubber layer, using ethylene propylene rubber (EPDM) or butyl rubber (IIR), which has good insulation and water and gas barrier properties.

[0024] In addition, the outer shielding layer 102 is preferably an aluminum foil layer to ensure the shielding performance of the cable and improve the cable's electrical conductivity and mechanical strength.

[0025] In addition, the water-blocking filling layer 104 is preferably a water-blocking paste, water-blocking powder, or water-blocking tape, used to absorb water vapor that diffuses into the cable, so that the cable can be kept under safe operating conditions with low relative humidity for a long time.

[0026] In addition, the insulation layer 105 is preferably a cross-linked polyethylene insulation layer, which has excellent heat resistance, insulation, mechanical strength and chemical resistance, and is durable and has a long service life.

[0027] In addition, the inner sheath 103 and the outer sheath 106 are preferably lead sheath, aluminum sheath, and stainless steel sheath, respectively; wherein, the thickness of the inner sheath 103 is less than the thickness of the outer sheath 106, and the outer sheath 106 comes into contact with the external pressure first, which enhances the pressure resistance of the outer sheath 106, while also reducing the overall weight of the cable without affecting the overall performance.

[0028] In addition, preferably the thickness of the inner filling layer 101 is greater than the thickness of the water-blocking filling layer 104, so as to provide relative water-blocking protection for the conductor core 10. When the external structure fails, the water-blocking protection time can be extended, providing time for the next step of troubleshooting and emergency repair.

[0029] It should be noted that, in this document, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0030] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A waterproof cross-linked polyethylene insulated medium-voltage DC cable, characterized in that: It includes a conductor core (10), an inner shielding layer (100), an inner filling layer (101), an outer shielding layer (102), an inner sheath (103), a water-blocking filling layer (104), an insulation layer (105), and an outer sheath (106). The outer layer of the conductor core (10) is provided with an inner shielding layer (100). The outer layer of the inner shielding layer (100) is provided with an inner filling layer (101). The outer layer of the inner filling layer (101) is provided with an outer shielding layer (102). The outer shielding layer (102) is provided with an inner sheath (103) on its outer layer. The outer layer of the inner sheath (103) is provided with a water-resistant filling layer (104). An insulating layer (105) is provided on the outer layer of the water-blocking filling layer (104). The outer layer of the insulating layer (105) is provided with an outer sheath (106). Among them, the inner sheath (103) and the outer sheath (106) are metal sheaths.

2. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The inner shielding layer (100) is a copper wire braided mesh layer.

3. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The inner filling layer (101) is a water-resistant rubber layer.

4. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The outer shielding layer (102) is an aluminum foil layer.

5. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The water-blocking filler layer (104) is a water-blocking paste, water-blocking powder, or water-blocking tape.

6. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The insulation layer (105) is a cross-linked polyethylene insulation layer.

7. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The inner sheath (103) and the outer sheath (106) are respectively lead sheaths or aluminum sheaths; The thickness of the inner sheath (103) is less than the thickness of the outer sheath (106).

8. The waterproof cross-linked polyethylene insulated medium-voltage DC cable according to claim 1, characterized in that: The thickness of the inner filling layer (101) is greater than the thickness of the water-blocking filling layer (104).

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