220kV water-blocking high-voltage cable

Abstract

This utility model discloses a 220kV water-blocking high-voltage cable, comprising a core layer (1) and a protective layer (2). The protective layer (2) is disposed on the outer ring of the core layer (1) to ensure the quality of the core layer (1). The protective layer (2) includes a corrugated aluminum sheath (2.1), a water-blocking adhesive filling layer (2.2), and a semi-conductive buffer strip (2.3). The water-blocking adhesive filling layer (2.2) is disposed on the outer layer of the corrugated aluminum sheath (2.1), and the semi-conductive buffer strip (2.3) is disposed on the inner layer of the corrugated aluminum sheath (2.1). This utility model provides a 220kV water-blocking high-voltage cable that requires only one water-blocking layer structure to ensure the water-blocking effect of the cable protective layer, thereby avoiding reduced production efficiency and avoiding ablation.

Description

Technical Field

[0001] This utility model relates to the field of cables, specifically a 220kV water-blocking high-voltage cable. Background Technology

[0002] In traditional medium and high voltage cables, a corrugated aluminum sheath and an asphalt filler layer are added to the cable's protective layer to improve its mechanical strength and water-blocking performance. However, the water-blocking effect of the asphalt filler layer mainly relies on the hydrophobic properties of asphalt, requiring full and sufficient filling to guarantee the water-blocking effect. Therefore, to address the possibility of incomplete filling of the asphalt layer, a water-blocking layer structure is added inside the corrugated aluminum sheath to achieve a double water-blocking seal, ensuring the safety of medium and high voltage cables. However, this structure necessitates a double water-blocking layer processing step during cable production, leading to reduced production efficiency. Furthermore, some water-blocking layer structures use semi-conductive buffer water-blocking tape, where the water-blocking powder may precipitate, causing ablation in the high-voltage cable. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to provide a 220kV water-blocking high-voltage cable that only requires a single water-blocking layer structure to ensure the water-blocking effect of the cable protection layer, so as to avoid reduced production efficiency and avoid ablation.

[0004] The technical solution adopted by this utility model to solve the above problems is as follows: a 220kV water-blocking high-voltage cable, including a core wire layer and a protective layer. The protective layer is disposed on the outer ring of the core wire layer to ensure the quality of the core wire layer. The protective layer includes a corrugated aluminum sheath, a water-blocking adhesive filling layer and a semi-conductive buffer strip. The water-blocking adhesive filling layer is disposed on the outer layer of the corrugated aluminum sheath, and the semi-conductive buffer strip is disposed on the inner layer of the corrugated aluminum sheath.

[0005] Compared with existing technologies, the advantages of this invention are as follows: It directly replaces asphalt with a water-blocking adhesive to form a water-blocking adhesive filling layer on the outer layer of the corrugated aluminum sheath. This water-blocking adhesive is composed of a polymer substrate (silicone rubber, polyurethane) and a superabsorbent polymer (SAP). The water-blocking adhesive utilizes its water-absorbing properties to block water; after absorbing water, it expands, thus preventing water molecules from entering the cable. Its water-blocking effect is significantly better than that of an asphalt filling layer. Therefore, it eliminates the need to add a water-blocking layer to the inner layer of the corrugated aluminum sheath, reducing the processing steps of one water-blocking structure. Furthermore, if the original water-blocking structure uses a semi-conductive buffer water-blocking tape, it also avoids the risk of high-voltage cable failure or outage due to the burning of the semi-conductive buffer water-blocking tape, thereby improving the cable's lifespan. In addition to improving production efficiency, the water-blocking adhesive also possesses excellent modification capabilities. Modifiers can be added during the production process to enhance additional functions, such as insulation and anti-aging, depending on the application environment. Furthermore, adding a semi-conductive buffer strip to the inner layer of the corrugated aluminum sheath serves as a component for the transition from high to low potential within the cable, ensuring electrical connection and preventing partial discharge. While the number of steps in wrapping the semi-conductive buffer water-blocking tape is not reduced compared to wrapping the semi-conductive buffer tape, their effects differ. Moreover, the wrapping process for the semi-conductive buffer water-blocking tape demands higher precision and carries the risk of ablation; therefore, they cannot be described as equivalent processes.

[0006] As an improvement of this utility model, the outer layer of the water-blocking adhesive filling layer is provided with an outer sheath. The water-blocking adhesive filling layer saturates the gap between the outer sheath and the corrugated aluminum sheath. Through this improvement, the outer sheath provides the cable with mechanical protection, insulation protection, corrosion resistance, waterproofing, moisture resistance, and electromagnetic shielding, ensuring the safe and reliable operation of the cable under various environmental conditions. It is the basic structure of the cable. During the molding process, the outer sheath is formed by extrusion. Therefore, the inner ring structure of the outer sheath is formed based on the water-blocking adhesive filling layer. The saturation filling of the water-blocking adhesive filling layer ensures the molding quality of the outer sheath and guarantees the safety of the cable.

[0007] As an improvement of this utility model, the outer sheath is provided with a semi-conductive layer. The semi-conductive layer is used to ensure the grounding connection of the cable. With this improvement, before the high-voltage cable is used, it is necessary to conduct a high-voltage withstand test. Through the design of the semi-conductive layer, an excellent physical and electrical connection can be formed, thereby achieving a uniform electric field distribution, ensuring the consistency of current distribution, reducing the accumulation of space charge or dielectric breakdown caused by local electric field differences, and improving the testing safety of the high-voltage cable in the high-voltage withstand test. At the same time, the semi-conductive layer can improve the insulation performance of the cable and effectively suppress the interference of external electric fields on the cable insulation layer, thereby ensuring the accuracy of the high-voltage withstand test.

[0008] As an improvement of this utility model, the semiconductive layer is made by overlapping semiconductive wrapping tape around the outer layer of the outer sheath.

[0009] As an improvement of this utility model, the semiconductive layer is coated on the outer layer of the outer sheath.

[0010] As an improvement of this utility model, the inner layer of the semi-conductive buffer strip is provided with an insulating shielding layer, and the semi-conductive buffer strip is wrapped around the insulating shielding layer. The inner end face of the corrugated aluminum sleeve abuts against the semi-conductive buffer strip. Through this improvement, the semi-conductive buffer strip abuts against the insulating shielding layer and the corrugated aluminum sleeve, forming a good electrical connection, uniform electric field distribution, and preventing partial discharge. At the same time, it also reduces the induced voltage between the insulating shielding layer and the corrugated aluminum sleeve, reducing the risk of discharge when the cable is subjected to impact. In addition, the semi-conductive buffer strip can buffer the mechanical impact during cable laying or operation, and reduce frictional damage between the insulating shielding layer and the aluminum sleeve. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the cross-sectional structure of this utility model.

[0012] Figure 2 This is a cross-sectional structural diagram of the wrinkled aluminum sleeve area of ​​this utility model.

[0013] The diagram shows: 1. Core wire layer, 2. Protective layer, 2.1. Corrugated aluminum sleeve, 2.2. Water-blocking adhesive filling layer, 2.3. Semi-conductive buffer strip, 2.4. Outer sheath, 2.5. Semi-conductive layer, 2.6. Insulating shielding layer. Detailed Implementation

[0014] The embodiments of this utility model will be further described below with reference to the accompanying drawings.

[0015] like Figure 1-2 As shown, a 220kV water-blocking high-voltage cable includes a core layer 1 and a protective layer 2. The protective layer 2 is disposed on the outer ring of the core layer 1 to ensure the quality of the core layer 1. The protective layer 2 includes a corrugated aluminum sheath 2.1, a water-blocking adhesive filling layer 2.2, and a semi-conductive buffer strip 2.3. The water-blocking adhesive filling layer 2.2 is disposed on the outer layer of the corrugated aluminum sheath 2.1, and the semi-conductive buffer strip 2.3 is disposed on the inner layer of the corrugated aluminum sheath 2.1. The outer layer of the water-blocking adhesive filling layer 2.2 is provided with an outer sheath 2.4. The water-blocking adhesive filling layer 2.2 saturates and fills the gap between the outer sheath 2.4 and the corrugated aluminum sheath 2.1. The inner layer of the semi-conductive buffer strip 2.3 is provided with an insulating shielding layer 2.6. The semi-conductive buffer strip 2.3 is wrapped around the insulating shielding layer 2.6, and the inner end face of the corrugated aluminum sheath 2.1 abuts against the semi-conductive buffer strip 2.3.

[0016] The outer sheath 2.4 is provided with a semi-conductive layer 2.5. The semi-conductive layer 2.5 is used to ensure the grounding connection of the cable. The semi-conductive layer 2.5 is wrapped around the outer sheath 2.4 with a semi-conductive wrapping tape, or it is coated on the outer sheath 2.4.

[0017] The core layer 1 is made of multiple strands of conductors twisted together. The protective layer 2 also includes a conductor shielding layer and an insulation layer. The conductor shielding layer is located on the outer layer of the core layer 1, and the insulation layer is located between the conductor shielding layer and the insulation shielding layer 2.6.

[0018] The design of the 220kV water-blocking high-voltage cable simplifies the traditional high-voltage cable design of corrugated aluminum sheath 2.1 + asphalt + water-blocking layer to a combination of corrugated aluminum sheath 2.1 and water-blocking adhesive filling layer 2.2. The water-blocking adhesive filling layer 2.2 replaces the asphalt area, thus reducing the design of the water-blocking layer. Although some designs use a semi-conductive buffer water-blocking tape as the water-blocking layer, which is a semi-conductive buffer layer pre-filled with water-blocking powder, the semi-conductive buffer water-blocking tape and the semi-conductive buffer tape have the same molding process in the production process. Although this also simplifies the process steps, the water-blocking powder has the risk of precipitation during long-term use, which can easily cause high-voltage ablation. In the design of the 220kV water-blocking high-voltage cable, the process steps were simplified while still ensuring the cable's quality and safety, and production efficiency was improved. Furthermore, the water-blocking adhesive filler layer 2.2 has a good modification basis, which increases the cable's adaptability. At the same time, the design of the semi-conductive buffer strip 2.3 and the semi-conductive layer 2.5 evenly distributes the internal and external electric fields of the cable, respectively, so that the cable operates in a stable electric field environment, ensuring the stability and safety of the cable's power transmission.

[0019] The above description only illustrates the preferred embodiment of this utility model and should not be construed as limiting the scope of the claims. This utility model is not limited to the above embodiments, and variations in its specific structure are permitted. All changes made within the scope of the independent claims of this utility model are also within the scope of protection of this utility model.

Claims

1. A 220kV water-blocking high-voltage cable, characterized in that: It includes a core wire layer (1) and a protective layer (2). The protective layer (2) is disposed on the outer ring of the core wire layer (1) to ensure the quality of the core wire layer (1). The protective layer (2) includes a corrugated aluminum sleeve (2.1), a water-blocking adhesive filling layer (2.2), and a semi-conductive buffer strip (2.3). The water-blocking adhesive filling layer (2.2) is disposed on the corrugated aluminum sleeve (2.1). 2.1) outer layer, the semi-conductive buffer strip (2.3) is disposed in the inner layer of the corrugated aluminum sleeve (2.1).

2. The 220kV water-blocking high-voltage cable according to claim 1, characterized in that: The outer layer of the water-blocking adhesive filling layer (2.2) is provided with an outer sheath (2.4), and the water-blocking adhesive filling layer (2.2) saturates the gap between the outer sheath (2.4) and the corrugated aluminum sleeve (2.1).

3. The 220kV water-blocking high-voltage cable according to claim 2, characterized in that: The outer sheath (2.4) is provided with a semi-conductive layer (2.5), which is used to ensure the grounding connection of the cable.

4. The 220kV water-blocking high-voltage cable according to claim 3, characterized in that: The semiconductive layer (2.5) is wrapped around the outer layer of the outer sheath (2.4) with a semiconductive wrapping tape.

5. The 220kV water-blocking high-voltage cable according to claim 3, characterized in that: The semiconductive layer (2.5) is coated on the outer layer of the outer sheath (2.4).

6. The 220kV water-blocking high-voltage cable according to claim 1, characterized in that: The inner layer of the semiconductive buffer strip (2.3) is provided with an insulating shielding layer (2.6), the semiconductive buffer strip (2.3) is wrapped around the insulating shielding layer (2.6), and the inner end face of the corrugated aluminum sleeve (2.1) abuts against the semiconductive buffer strip (2.3).

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