JP2023162588A - Cable connection structure, power cable, and method for manufacturing cable connection structure - Google Patents

Abstract

To provide a cable connection structure which is of a simple composition, yet has both water impermeability and electrical discontinuity.SOLUTION: In a connected power cable 10, a cable connection structure 20 has a sleeve 200 that connects a first power cable 100a and a second power cable 100b, an insulating unit 300 that covers the outer circumference of the sleeve, and a protection part 400 that protects portions of the insulating unit and the first power cable and a portion of the second power cable from the outside. The protection part has a first metal layer 410 that continuously covers the partial outer circumference of the first power cable and the outer circumference of the insulating unit in a region close to the first power cable, an insulating layer 420 that continuously covers the outer circumference of the insulating unit that is exposed from the first metal layer and the partial outer circumference of the first metal layer, and a second metal layer 430 that continuously covers the partial outer circumference of the second power cable and the outer circumference of the insulting layer in a region close to the second power cable, and that overlaps the insulating layer above a portion of the first metal layer. The second metal layer is insulated from the first metal layer by the insulating layer.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to cable connection structures, power cables, and methods of manufacturing cable connection structures.

In the past, a metal tube was sometimes provided to surround the connecting portion of a pair of power cables (for example, Patent Document 1).

Japanese Patent Application Publication No. 2015-142478

An object of the present disclosure is to achieve both waterproofness and electrical isolation with a simple configuration.

According to one aspect of the present disclosure,
a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
an insulating layer provided so as to continuously cover an outer periphery of the insulating unit exposed from the first metal layer and a part of the outer periphery of the first metal layer;
The insulating layer is provided so as to continuously cover a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and is provided above a part of the first metal layer. a second metal layer overlapping the layer;
has
The second metal layer is insulated from the first metal layer by the insulating layer. A cable connection structure is provided.

According to the present disclosure, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

FIG. 1 is a schematic cross-sectional view showing a power cable. FIG. 2 is a schematic cross-sectional view along the axial direction of a conductor, showing the cable connection structure according to the first embodiment of the present disclosure. FIG. 3A is an enlarged schematic cross-sectional view of a portion of the protection part according to the first embodiment of the present disclosure. FIG. 3B is an enlarged schematic cross-sectional view of a portion of the protection portion according to Modification 1-1 of the first embodiment of the present disclosure. FIG. 3C is an enlarged schematic cross-sectional view of a portion of the protection portion according to Modification 1-2 of the first embodiment of the present disclosure. FIG. 4 is a schematic cross-sectional view taken along the axial direction of a conductor, showing a cable connection structure according to a second embodiment of the present disclosure. FIG. 5A is an enlarged schematic cross-sectional view of a part of the protection part according to the second embodiment of the present disclosure. FIG. 5B is an enlarged schematic cross-sectional view of a portion of the protection portion according to Modification 2-1 of the second embodiment of the present disclosure.

[Description of embodiments of the present disclosure]
<Findings obtained by the inventors>
First, the findings obtained by the inventors will be explained.

As described above, in the conventional intermediate connection section where a pair of power cables are connected, a metal tube is provided to protect the outside of the insulation unit that covers the conductor connection tube, for example. The metal pipe ensured water-tightness.

Here, in order to separate the ground systems in the pair of power cables at the intermediate connection part, it may be necessary to electrically separate the metal tubes. Such a connection portion is sometimes referred to as an “insulated connection portion”. By providing an insulated connection part in each of the three-phase power cables and cross-bonding the cable metal shielding layer of the three-phase power cable to ground, it is possible to suppress the induced voltage generated in the cable metal shielding layer. Furthermore, by providing the insulated connection portion, excessive propagation of ground fault current can be suppressed, and the ground fault location can be easily identified.

In conventional insulated connections, by interposing a cylindrical insulator at an intermediate position in the axial direction of the metal tube, the metal tube in the area close to the first power cable and the metal tube in the area close to the second power cable are connected. , were separated. Such a configuration achieves both water-blocking properties and electrical isolation properties.

However, metal tubes with insulators have complicated and heavy structures. For this reason, it has become difficult to construct the insulated connection part, and the cost related to the insulated connection part has increased.

In order to solve such problems, the present inventor considered replacing the conventional metal tube with a sheet-like metal layer in the insulating connection part.

First, we considered a structure in which metal layers are separated by a predetermined spacing in the axial direction of the power cable at the insulated connection part, similar to conventional copper pipes. However, in such a structure, the water-blocking property in the spaced part is reduced, and moisture permeation occurs from the spaced part. In other words, since the metal layer does not cover the entire insulation unit, moisture permeation occurs.

Therefore, the inventors of the present invention have discovered a configuration in which the entire insulating unit is covered with a metal layer to ensure electrical interruption (also referred to as "edge-cutting ability") while maintaining high water-blocking properties.

The present disclosure below is based on the above findings discovered by the present disclosers.

<Embodiments of the present disclosure>
Next, embodiments of the present disclosure will be listed and described.

[1] A cable connection structure according to one aspect of the present disclosure includes:
a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
an insulating layer provided so as to continuously cover an outer periphery of the insulating unit exposed from the first metal layer and a part of the outer periphery of the first metal layer;
The insulating layer is provided so as to continuously cover a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and is provided above a part of the first metal layer. a second metal layer overlapping the layer;
has
The second metal layer is insulated from the first metal layer by the insulating layer.
According to this configuration, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

[2] A cable connection structure according to another aspect of the present disclosure,
a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided to cover at least a portion of the outer periphery of the first power cable;
a second metal layer provided to cover at least a portion of the outer periphery of the second power cable and spaced apart from the first metal layer across a predetermined space in the axial direction of the conductor;
an insulating layer provided so as to continuously cover a part of the outer periphery of the first metal layer, an outer periphery of the insulating unit exposed in the separation part, and a part of the outer periphery of the second metal layer;
a third metal layer provided to cover the outer periphery of the insulating layer and overlapping the insulating layer above both a portion of the first metal layer and a portion of the second metal layer;
has
The third metal layer is insulated from the first metal layer and the second metal layer by the insulating layer.
According to this configuration, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

[3] In the cable connection structure according to [1] or [2] above,
The insulation unit is
an inner semiconducting layer disposed to cover at least the outer periphery of the sleeve and having semiconductivity;
an insulating unit insulating layer that is provided to cover the outer periphery of each of the internal semiconductive layer, a part of the first power cable, and a part of the second power cable, and has an insulating property;
an outer semiconductive layer having semiconductivity and provided so as to cover the outer periphery of each of the insulating layer, a portion of the first power cable, and a portion of the second power cable;
has
The outer semiconducting layer has at least one separation section separated in the axial direction of the first power cable and the second power cable,
The insulating layer of the protection portion covers the separation portion while being in contact with the separation portion of the insulation unit.
According to this configuration, it is possible to stably ensure electrical disconnection of the cable connection structure.

[4] In the cable connection structure according to any one of [1] to [3] above,
A plurality of the insulating layers are laminated.
According to this configuration, the insulation properties of the portion where the first metal layer and the second metal layer are insulated by the insulating layer can be improved.

[5] A power cable according to still another aspect of the present disclosure,
At least one cable connection structure according to any one of [1] to [4] above is provided and connected.
According to this configuration, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

[6] A method for manufacturing a cable connection structure according to still another aspect of the present disclosure,
providing a first power cable and a second power cable each having a conductor;
connecting the conductor of the first power cable and the conductor of the second power cable with a cylindrical sleeve;
providing an insulating unit that maintains insulation around the sleeve so as to cover the outer periphery of the sleeve;
providing a protective portion to protect the outside of the insulation unit, a portion of the first power cable, and a portion of the second power cable;
has
The step of providing the protection portion includes:
providing a first metal layer so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
providing an insulating layer so as to continuously cover the outer periphery of the insulating unit exposed from the first metal layer and the outer periphery of a part of the first metal layer;
Continuously covers a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and overlaps the insulating layer above a part of the first metal layer. a step of providing a second metal layer,
has
In the step of providing the second metal layer,
The second metal layer is insulated from the first metal layer by the insulating layer.
According to this configuration, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

[7] A method for manufacturing a cable connection structure according to still another aspect of the present disclosure,
providing a first power cable and a second power cable each having a conductor;
connecting the conductor of the first power cable and the conductor of the second power cable with a cylindrical sleeve;
providing an insulating unit that maintains insulation around the sleeve so as to cover the outer periphery of the sleeve;
providing a protective portion to protect the outside of the insulation unit, a portion of the first power cable, and a portion of the second power cable;
has
The step of providing the protection portion includes:
providing a first metal layer so as to cover at least a portion of the outer periphery of the first power cable;
providing a second metal layer so as to cover at least a portion of the outer periphery of the second power cable and to be spaced apart from the first metal layer across a predetermined space in the axial direction of the conductor;
providing an insulating layer so as to continuously cover a part of the outer periphery of the first metal layer, a part of the outer periphery of the insulating unit exposed in the spaced part, and a part of the second metal layer;
providing a third metal layer so as to cover the outer periphery of the insulating layer and overlap the insulating layer above both a portion of the first metal layer and a portion of the second metal layer;
has
In the step of providing the third metal layer,
The third metal layer is insulated from the first metal layer and the second metal layer by the insulating layer.
According to this configuration, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

[Details of embodiments of the present disclosure]
Next, a first embodiment of the present disclosure will be described below with reference to the drawings. Note that the present disclosure is not limited to these examples, but is indicated by the scope of the claims, and is intended to include all changes within the meaning and scope equivalent to the scope of the claims.

<First embodiment of the present disclosure>
(1) Connected power cables and cable connection structure See FIGS. 1 and 2 for the schematic configuration of the connected power cables 10 and cable connection structure (cable connection part) 20 according to the first embodiment of the present disclosure. and explain

Note that in FIG. 2, the configuration of the lower half is omitted. In FIG. 2, the stripped power cable 100 and sleeve 200 are shown in side view.

As shown in FIG. 2, the connected power cable 10 of this embodiment includes, for example, a plurality of power cables 100 and at least one cable connection structure 20.

In addition, in the following, the "axial direction" of the power cable 100 etc. refers to the direction along the central axis of the power cable 100 etc., and can be paraphrased as the longitudinal direction of the power cable 100 etc. Further, the "radial direction" of the power cable 100 etc. refers to a direction perpendicular to the axial direction of the power cable 100 etc., and can be translated as the lateral direction of the power cable 100 etc. in some cases. Moreover, the "circumferential direction" of the power cable 100 etc. refers to the direction along the outer periphery of the power cable 100 etc.

[First power cable and second power cable]
As shown in FIG. 1, power cable 100 is configured as a solid insulated cable that is a high voltage power transmission cable.

The power cable 100 shown in FIG. 1 is configured, for example, as a land cable or an underground cable, and includes a conductor 110, a cable inner semiconducting layer 120, a cable insulating layer 130, a cable outer semiconducting layer 140, a water absorption layer (not shown), The cable metal shielding layer 150 and the cable sheath 160 are provided in this order from a region close to the central axis of the conductor 110 toward the outer periphery. Note that the portion of the power cable 100 from the conductor 110 to the cable external semiconductive layer 140 is sometimes referred to as a "cable core." Cable insulation layer 130 includes polyolefin such as polyethylene. The polyolefin may be crosslinked. Cable metal shielding layer 150 is, for example, a metal sheath or a wrapped layer of copper wire or copper tape.

The conductor 110 includes, for example, a plurality of conductor strands 112. In each conductor strand layer 114, the plurality of conductor strands 112 are provided, for example, twisted together in a spiral along the outer peripheral surface of the inner layer. The conductor wire 112 contains, for example, at least one of copper and aluminum.

As shown in FIG. 2, the power cable 100 is stripped in stages from the tip of the conductor 110 toward the opposite side (so-called "step stripped"). That is, the conductor 110, the cable inner semiconducting layer 120, the cable insulation layer 130, the cable outer semiconducting layer 140, the cable metal shielding layer 150, and the cable sheath 160 are exposed in this order from the tip of the conductor 110 in the opposite direction. ing. Hereinafter, each section that has been stripped off may be referred to as an "exposed section." With such a configuration, the power cables 100 can be connected to each other in order from an area close to the central axis toward the outer periphery.

As shown in FIG. 2, a plurality of power cables 100 are provided. Among the plurality of power cables 100, a pair of power cables 100 are butted against each other with the axes of their conductors 110 aligned. Note that, hereinafter, one power cable 100 of the pair of power cables 100 may be referred to as a "first power cable 100a", and the other power cable 100 may be referred to as a "second power cable 100b".

[Cable connection structure]
As shown in FIG. 2, the cable connection structure 20 is configured to connect a pair of power cables 100, for example, as a so-called insulated connection part. Specifically, the cable connection structure 20 includes, for example, the pair of power cables 100 described above, a sleeve (conductor connection tube) 200, an insulation unit (insulation tube, rubber connection tube, rubber unit) 300, and a protection part 400. It has .

(sleeve)
The sleeve 200 is configured, for example, as a cylindrical metal tube, and is provided so as to surround the respective tips of the pair of conductors 110 so as to connect the conductors 110 of the pair of power cables 100. Note that the cylindrical sleeve 200 may have a partition wall (not shown) between the pair of conductors 110 in the hollow portion.

Note that, for example, a semiconductive tape may be wrapped so as to fill the space between the pair of cable insulation layers 130. Thereby, uneven surface pressure of the insulation unit 300, which will be described later, can be suppressed.

(insulation unit)
The insulating unit 300 is configured as, for example, an insulating cylindrical member, and is provided so as to cover the outer periphery of the sleeve 200 .

The insulation unit 300 is configured, for example, as a so-called cold shrink type or a factory expanded type. That is, the insulating unit 300 has an elastic material that is integrally molded, and is configured to elastically contract at room temperature and come into close contact with the connecting portion of the power cable 100.

Furthermore, the insulation unit 300 is configured to, for example, maintain insulation around the sleeve 200 while relaxing the electric field around the sleeve 200. Specifically, the insulating unit 300 includes, for example, an inner semiconducting layer 320, an insulating unit insulating layer 340, and an outer semiconducting layer 380.

The internal semiconductive layer 320 has a cylindrical shape so as to cover the outer periphery of the sleeve 200. The internal semiconductive layer 320 includes, for example, semiconductive rubber. The internal semiconducting layer 320 is at the same potential as the sleeve 200.

The insulating unit insulating layer 340 is provided so as to cover the respective outer peripheries of the internal semiconducting layer 320, a portion of the first power cable 100a, and a portion of the second power cable 100b. The insulation unit insulation layer 340 includes, for example, rubber having insulation properties.

The external semiconducting layer 380 is provided so as to cover the respective outer peripheries of the insulating unit insulating layer 340, a portion of the first power cable 100a, and a portion of the second power cable 100b. The outer semiconductive layer 380 includes semiconductive rubber.

The outer semiconducting layer 380 has, for example, a stress cone portion 360. The stress cone portions 360 are provided at positions close to both ends of the insulation unit insulation layer 340 in the axial direction, and have a substantially tapered inner peripheral surface whose diameter increases toward the center of the insulation unit insulation layer 340 in the axial direction. are doing. A portion of the inner circumferential surface of the stress cone portion 360 is in contact with the cable outer semiconductive layer 140 of the step-stripped power cable 100.

With this configuration of the insulation unit 300, the electric field at the tip of the cable outer semiconductive layer 140 can be alleviated while electrically shielding the periphery of the sleeve 200.

Here, in this embodiment, the outer semiconducting layer 380 has at least one separation part SP separated in the axial direction of the first power cable 100a and the second power cable 100b. One separating section SP here is provided, for example, at a position close to the second power cable 100b, and separates a region close to the first power cable 100a and a region close to the second power cable 100b. Thereby, the insulation unit 300 can be electrically isolated between the shielding of the first power cable 100a and the shielding of the second power cable 100b.

Note that when both ends of the insulating unit 300 in the axial direction have end faces perpendicular to the axial direction, the inclination is reduced by wrapping a semiconductive tape (not shown) around the end faces. may be formed.

(Protection Department)
The protection part 400 is provided so as to cover the outer periphery of the insulating unit 300 and a part of the outer periphery of each of the pair of power cables 100, and is configured to protect the outside thereof. The protection unit 400 of this embodiment will be described in detail later.

(Configuration outside the protection part 400)
Outside the protective portion 400 in the axial direction of the conductor 110, the shielding of the first power cable 100a (cable metal shielding layer 150) and the shielding of the second power cable 100b (cable metal shielding layer 150) are grounded. Connected to the grid. In the case of cross-bond grounding, each of the shielding of the first power cable 100a and the shielding of the second power cable 100b is connected to the shielding of the other phase in the adjacent section.

In addition, a coffin box (not shown) may be provided to surround the protection part 400, if necessary. Thereby, the protection part 400 can be protected from external damage.

(2) Protection Unit The protection unit 400 according to the first embodiment of the present disclosure will be described with reference to FIGS. 2 and 3A. Note that in FIG. 3A and FIGS. 3B and 3C to be described later, components other than the protective section 400 and the outermost insulating layer 490 are omitted, and the lower surface of the protective section 400 is shown flat for simplicity.

As shown in FIGS. 2 and 3A, the protection unit 400 of this embodiment has, for example, a sandwich structure including a metal layer/insulating layer/metal layer as an electrical isolation structure. Specifically, the protective section 400 includes, for example, a first metal layer 410, an insulating layer (resin layer, protective insulating layer) 420, a second metal layer 430, and an outermost insulating layer 490. There is.

The first metal layer 410 is, for example, a part of the outer periphery of the first power cable 100a (cable external semiconductive layer 140 exposed in the first power cable 100a) and the outer periphery of the insulation unit 300 in a region close to the first power cable 100a. It is provided to cover continuously. Note that a portion of the first metal layer 410 may extend to a position closer to the second power cable 100b than the axial center of the insulation unit 300.

Specifically, the first metal layer 410 includes, for example, a rectangular solid metal sheet. Examples of the metal constituting the sheet of the first metal layer 410 include aluminum and aluminum alloy. For example, the first metal layer 410 extends from a part of the outer periphery of the first power cable 100a to the insulation unit 300 in a region close to the first power cable 100a such that the long side of the sheet is along the central axis of the first power cable 100a. It is wrapped around the area up to the outer periphery of the The wound first metal layers 410 are overlapped so that no separation occurs. Note that the first metal layer 410 may be wrapped, for example, by the so-called longitudinal wrapping described above, or by spiral wrapping.

Note that the first metal layer 410 may have, for example, a two-layer structure. Specifically, the first metal layer 410 includes, for example, a first metal shielding layer including a metal mesh tape and a first metal water-blocking layer including a metal sheet from an area close to the insulation unit 300 toward the outer periphery. They may be included in this order. The tape of the first metal shielding layer is, for example, a copper mesh tape. The first metal shielding layer is configured as a layer that confines the electric field formed by the high potential conductor 110 inside the insulation unit 300. The first metal shielding layer has, for example, a cross-sectional area (capacity) sufficient to allow a short-circuit current to flow at the time of dielectric breakdown. On the other hand, the first metal water-blocking layer is configured, for example, as a layer that prevents moisture from entering the insulating unit 300 from outside (water-blocking). The first metal water barrier layer does not require a cross-sectional area like the first metal barrier layer, but the first metal water barrier layer is made of, for example, a solid metal sheet with no gaps to prevent moisture from passing through. have. With such a configuration, the functions can be separated between the first metal shielding layer having excellent electrical shielding properties and the first metal water shielding layer having excellent water shielding properties.

The insulating layer 420 is provided, for example, so as to continuously cover the outer periphery of the insulating unit 300 exposed from the first metal layer 410 and the outer periphery of a part of the first metal layer 410.

Specifically, the insulating layer 420 includes, for example, a heat-shrinkable insulating tube or an insulating tape. Examples of the material constituting the insulating layer 420 include polyethylene and silicone rubber. The overlapping portion of the first metal layer 410 described above is fixed by such an insulating layer 420.

The second metal layer 430 includes, for example, a part of the outer periphery of the second power cable 100b (cable external semiconductive layer 140 exposed in the second power cable 100b) and the outer periphery of the insulating layer 420 in a region close to the second power cable 100b. It is provided to cover continuously. Furthermore, the second metal layer 430 overlies the insulating layer 420 over a portion of the first metal layer 410, for example.

Specifically, the second metal layer 430 has a rectangular metal sheet, for example, similar to the first metal layer 410. The second metal layer 430 is formed, for example, from a partial outer periphery of the second power cable 100b so that the long side of the sheet runs along the second power cable 100b, to the outer periphery of the insulating layer 420 in a region close to the second power cable 100b, and is wound around a part of the first metal layer 410 up to the outer periphery. The wound second metal layers 430 are overlapped so that no separation occurs.

Note that the second metal layer 430 may have a two-layer structure, for example, similarly to the first metal layer 410. Specifically, the second metal layer 430 includes, for example, a second metal shielding layer including a metal mesh tape and a second metal water shielding layer including a metal sheet from an area close to the insulation unit 300 toward the outer periphery. They may be included in this order. The tape of the second metal shielding layer is, for example, a copper mesh tape. The first metal water-blocking layer has a solid metal sheet with no gaps. The respective functions of the second metal shielding layer and the second metal water shielding layer are similar to the respective functions of the first metal shielding layer and the first metal water shielding layer described above.

On the other hand, in this embodiment, the second metal layer 430 overlaps the insulating layer 420 above a part of the first metal layer 410 as described above, so that the insulating layer 420 makes the first metal layer 410 is insulated. Thereby, the shielding of the first power cable 100a and the shielding of the second power cable 100b can be electrically separated.

Furthermore, in the present embodiment, the insulating layer 420 of the protective section 400 is in contact with and covers the separating part SP of the external semiconducting layer 380 of the insulating unit 300, for example. In other words, the insulating layer 420 of the protection part 400 directly overlaps the separation part SP of the outer semiconducting layer 380 of the insulating unit 300. Thereby, the electrically isolated location of the protection part 400 and the isolation part SP of the insulation unit 300 can be matched.

Note that as long as the insulation distance of the electrically isolated points of the cable connection structure 20 as a whole is secured, even if the electrically separated points of the protection part 400 and the separated part SP of the insulation unit 300 do not completely match, good. For example, either the electrically isolated part of the protection part 400 or the separated part SP of the insulation unit 300 may be small, or may be shifted in the axial direction of the conductor 110.

Further, in this embodiment, the insulating layer 420 extends outward from the end of the second metal layer 430 in the axial direction of the conductor 110, for example. Thereby, short circuit between the end of the second metal layer 430 and the first metal layer 410 can be suppressed. As a result, the electrical disconnection described above can be stably maintained.

Furthermore, in this embodiment, the outermost insulating layer 490 is provided at the outermost periphery of the protective section 400. Specifically, the outermost insulating layer 490 includes, for example, a heat-shrinkable insulating tube or an insulating tape. For example, the outermost insulating layer 490 continuously covers the outer periphery of the first metal layer 410 exposed from the insulating layer 420, the outer periphery of the insulating layer 420 exposed from the second metal layer 430, and the outer periphery of the second metal layer 430. It is set up like this. The overlapping portion of the second metal layer 430 described above is fixed by the outermost insulating layer 490. As a result, it is possible to stably maintain water-blocking properties and electrical isolation properties in the protection section 400.

(3) Manufacturing method of cable connection structure (method of manufacturing connected power cables, cable connection method)
Next, a method for manufacturing the cable connection structure according to this embodiment will be described with reference to FIGS. 1 to 3A.

The method for manufacturing the cable connection structure 20 of this embodiment includes, for example, a preparation step S10, a conductor connection step S20, an insulation unit arrangement step S30, and a protection part formation step S40.

(S10: Preparation process)
First, the members of each layer of the pair of power cables 100, the sleeve 200, the insulation unit 300, and the protection part 400 that constitute the cable connection structure 20 are prepared.

For example, in a factory, an inner core ribbon (not shown) is spirally wound in advance to form a cylindrical inner core (not shown), and the inner core is inserted into the hollow portion of the insulation unit 300. Thereby, the diameter of the insulation unit 300 is expanded.

Next, for example, at the site where the power cables 100 are laid, the pair of power cables 100 are peeled off in stages from one end in the axial direction. As a result, the conductor 110, the cable insulating layer 130, the cable outer semiconducting layer 140, and the cable sheath 160 are exposed in this order from the tip of the power cable 100.

After preparing each member constituting the cable connection structure 20, the insulation unit 300 and the protection part 400 are passed through the power cable 100, and the insulation unit 300 and the insulation layer 420 and the outermost insulation layer 490 of the protection part 400 are heated. The shrinkable insulating tube is released at a predetermined position on the power cable 100.

(S20: Conductor connection process)
After the preparation step S10 is completed, the pair of power cables 100 are butted against each other within the sleeve 200 with the axes of their conductors 110 aligned. After the pair of power cables 100 are butted together, the conductors 110 of the pair of power cables 100 are compressed and connected using the sleeve 200.

Note that a semiconductive tape may be wrapped so as to fill the space between the pair of cable insulation layers 130.

(S30: Insulation unit arrangement step)
After the conductor connection step S20 is completed, an insulation unit 300 that maintains insulation around the sleeve 200 is provided to cover the outer periphery of the sleeve 200. Specifically, the insulation unit 300 whose diameter has been expanded by the inner core is moved to a position where it overlaps with the sleeve 200. After the insulation unit 300 is placed in a predetermined position, the inner core ribbon is gradually unraveled, and the diameter of the insulation unit 300 is gradually reduced in the axial direction. In this way, the insulation unit 300 is arranged so as to cover the outer periphery of the sleeve 200 and a portion of the outer periphery of each of the pair of power cables 100.

(S40: Protective part forming step)
After the insulation unit 300 is arranged, a protection part 400 is provided to protect the outside of the insulation unit 300, a part of the first power cable 100a, and a part of the second power cable 100b.

The protective portion forming step S40 of this embodiment includes, for example, a first metal layer forming step S41, an insulating layer forming step S42, a second metal layer forming step S43, and an outermost insulating layer forming step S49. ing.

(S41: First metal layer forming step)
First, a metal sheet is wrapped so as to continuously cover a portion of the outer periphery of the first power cable 100a and the outer periphery of the insulation unit 300 in a region close to the first power cable 100a. This provides the first metal layer 410.

(S42: Insulating layer forming step)
After providing the first metal layer 410, move the insulating tube released in advance to a position where it overlaps the outer periphery of the insulating unit 300 exposed from the first metal layer 410 and the outer periphery of a part of the first metal layer 410, Heat shrink the insulating tube. In this way, the insulating layer 420 is provided so as to continuously cover the outer periphery of the insulating unit 300 exposed from the first metal layer 410 and the outer periphery of a part of the first metal layer 410.

Note that an insulating tape may be wound as the insulating layer 420. In this case, unlike insulating tubes, there is no need to release the material in advance, and the working time can be shortened.

At this time, in this embodiment, the insulating layer 420 of the protection part 400 is brought into contact with the separation part SP of the external semiconducting layer 380 of the insulation unit 300, and the separation part SP is covered by the insulating layer 420.

Note that at this time, the overlapping portion of the first metal layer 410 is fixed by heat-shrinking the insulating tube constituting the insulating layer 420.

(S43: Second metal layer forming step)
Once the insulating layer 420 is provided, it continuously covers a part of the outer periphery of the second power cable 100b and the outer periphery of the insulating layer 420 in a region close to the second power cable 100b, and also covers a part of the upper part of the first metal layer 410. A metal sheet is wrapped around the insulating layer 420 so as to overlap it. This provides the second metal layer 430.

At this time, in this embodiment, by overlapping the second metal layer 430 on the insulating layer 420 above a part of the first metal layer 410, the insulating layer 420 allows the first metal layer 410 and the second metal layer to overlap. 430.

(S49: Outermost insulating layer forming step)
After forming the second metal layer 430, the insulating tube released in advance is placed around the outer periphery of the first metal layer 410 exposed from the insulating layer 420, the outer periphery of the insulating layer 420 exposed from the second metal layer 430, and the second metal layer 430. It is moved to a position overlapping the outer periphery of layer 430, and the insulating tube is heat-shrinked. In this way, the outer periphery of the first metal layer 410 exposed from the insulating layer 420, the outer periphery of the insulating layer 420 exposed from the second metal layer 430, and the outer periphery of the second metal layer 430 are continuously covered. An outer insulating layer 490 is provided.

Note that at this time, the overlapping portion of the second metal layer 430 is fixed by heat-shrinking the insulating tube constituting the outermost insulating layer 490.

Thereafter, the shield of the first power cable 100a and the shield of the second power cable 100b are each directly connected to the ground system. Furthermore, a coffin box is provided to surround the protection part 400, if necessary.

Through the above steps, the cable connection structure 20 of this embodiment is manufactured.

(4) Summary of the present embodiment According to the present embodiment, one or more of the following effects can be achieved.

(a) In this embodiment, the protection part 400 has a sandwich structure including a first metal layer 410/insulating layer 420/second metal layer 430 as an electrically isolated structure. That is, the second metal layer 430 covering the outer periphery of the area near the second power cable 100b is placed on the insulating layer 420 above a part of the first metal layer 410 covering the outer periphery of the area near the first power cable 100a. overlapping.

In this way, by overlapping the first metal layer 410, the insulating layer 420, and the second metal layer 430 in this order, a portion of the outer periphery of the first power cable 100a, the outer periphery of the insulation unit 300, and the second power cable 100b are overlapped. A part of the outer periphery can be seamlessly covered by the first metal layer 410 and the second metal layer 430 having water-blocking properties. Thereby, the water-blocking properties of the cable connection structure 20 can be ensured.

Further, the second metal layer 430 overlaps the insulating layer 420 above the first metal layer 410, so that the first metal layer 410 connected to the shield of the first power cable 100a and the second power cable 100b are connected to each other. The second metal layer 430 connected to the shield can be insulated in the thickness direction by the insulating layer 420. Thereby, the shielding of the first power cable 100a and the shielding of the second power cable 100b can be electrically separated. That is, even with a simple configuration, the induced voltage generated in the cable metal shielding layer 150 of the three-phase power cable can be stably suppressed. Further, the propagation of the ground fault current can be stably suppressed, and the ground fault location can be easily and stably identified.

As a result, according to the present embodiment, it is possible to achieve both water-blocking properties and electrical isolation properties with a simple configuration.

(b) In the present embodiment, the insulating layer 420 of the protection part 400 is in contact with the separation part SP of the external semiconducting layer 380 of the insulation unit 300 and covers the separation part SP. Thereby, the electrically isolated location of the protection part 400 and the isolation part SP of the insulation unit 300 can be matched. As a result, the electrical connection between the shielding of the first power cable 100a and the shielding of the second power cable 100b due to the misalignment between the electrically isolated point of the protection part 400 and the separated part SP of the insulation unit 300 is prevented. Can be suppressed. In other words, it is possible to stably ensure electrical disconnection of the cable connection structure 20.

(5) Modifications of the first embodiment The above-described embodiment can be modified as required as shown in the following modifications. Hereinafter, only elements that are different from the above-described embodiments will be described, and elements that are substantially the same as those described in the above-mentioned embodiments will be given the same reference numerals and their explanations will be omitted.

Modifications 1-1 and 1-2 of this embodiment will be described with reference to FIGS. 3B and 3C, respectively.

<Modification 1-1>
As shown in FIG. 3B, in Modification 1-1, the end of the insulating layer 420 in the axial direction of the conductor 110 coincides with the end of the second metal layer 430, for example.

Further, in Modification 1-1, the insulating layer 420 extends longer than the separation part SP of the insulating unit 300 in the axial direction of the conductor 110, for example, below the second metal layer 430. Thereby, it is possible to tolerate misalignment (positional shift) between the electrically isolated portion of the protection portion 400 and the separation portion SP of the insulation unit 300. As a result, it becomes possible to stably ensure electrical disconnection of the cable connection structure 20.

<Modification 1-2>
As shown in FIG. 3C, in Modification 1-2, a plurality of insulating layers 420 are laminated, for example. Here, the insulating layer 420 is stacked in two layers. This allows the total thickness of the insulating layer 420 to be increased between the first metal layer 410 and the second metal layer 430. As a result, the insulation of the portion where the first metal layer 410 and the second metal layer 430 are insulated by the insulating layer 420 can be improved.

<Second embodiment of the present invention>
Next, a second embodiment of the present invention will be described. Hereinafter, similarly to the above-mentioned modification 1-1, etc., explanations of elements that are substantially the same as those described in the above-described embodiment will be omitted as appropriate.

(1) Protective part As shown in FIGS. 4 and 5A, the protective part 400 of this embodiment has, for example, a sandwich structure including a metal layer/insulating layer/metal layer at two locations as an electrical isolation structure. are doing. Specifically, the protection section 400 includes, for example, a first metal layer 440, a second metal layer 450, an insulating layer 460, a third metal layer 470, and an outermost insulating layer 490. .

The first metal layer 440 is provided, for example, so as to cover at least a portion of the outer periphery of the first power cable 100a. Here, for example, similarly to the first embodiment, the first metal layer 440 continuously covers a part of the outer periphery of the first power cable 100a and the outer periphery of the insulation unit 300 in a region close to the first power cable 100a. It is set up like this. Note that a portion of the first metal layer 440 may extend to a position closer to the second power cable 100b than the axial center of the insulation unit 300.

The second metal layer 450 is provided, for example, so as to cover at least a portion of the outer periphery of the second power cable 100b, and is spaced apart from the first metal layer 440 with a predetermined space in between in the axial direction of the conductor 110. Here, for example, the second metal layer 450 is provided only on a part of the outer periphery of the second power cable 100b (cable external semiconductive layer 140 exposed in the second power cable 100b), and covers the outer periphery of the insulation unit 300. do not have.

Note that the first metal layer 440 and the second metal layer 450 have rectangular metal sheets similarly to the first embodiment. The wound first metal layer 440 and second metal layer 450 are overlapped so that no separation occurs.

The insulating layer 460 covers, for example, the outer periphery of a part of the first metal layer 440, the outer periphery of the insulating unit 300 exposed in the space between the first metal layer 440 and the second metal layer 450, and the outer periphery of the second metal layer 450. It is provided so as to continuously cover a part of the outer periphery.

The overlapping portions of the first metal layer 440 and the second metal layer 450 described above are fixed by the insulating layer 460.

Further, in the present embodiment, the insulating layer 460 of the protection part 400 is connected to the separation part SP of the external semiconducting layer 380 of the insulating unit 300, for example, in the separation part between the first metal layer 440 and the second metal layer 450. It covers the separation part SP while being in contact with it.

The third metal layer 470 is, for example, provided so as to (continuously) cover the outer periphery of the insulating layer 460 and above both a part of the first metal layer 440 and a part of the second metal layer 450. It overlaps the insulating layer 460. Thereby, the third metal layer 470 is insulated from the first metal layer 440 and the second metal layer 450 by the insulating layer 460.

Note that, like the first metal layer 440 and the second metal layer 450, the third metal layer 470 is also configured as a rectangular sheet containing metal. The wound third metal layer 470 is overlapped so that no separation occurs.

Further, in this embodiment, the above-mentioned insulating layer 460 extends outward from the end of the third metal layer 470 in the axial direction of the conductor 110, for example. Thereby, short circuit between the end of the third metal layer 470 and either the first metal layer 440 or the second metal layer 450 can be suppressed. As a result, the electrical disconnection described above can be stably maintained.

The outermost insulating layer 490 is provided at the outermost periphery of the protective section 400. The overlapping portion of the third metal layer 470 described above is fixed by the outermost insulating layer 490.

(2) Method for manufacturing cable connection structure The protective portion forming step S40 of this embodiment includes, for example, a first metal layer forming step S44, a second metal layer forming step S45, an insulating layer forming step S46, and a third metal layer forming step S45. It includes a layer forming step S47 and an outermost insulating layer forming step S49.

(S44: First metal layer forming step)
A first metal layer 440 is provided to cover at least a portion of the outer periphery of the first power cable 100a.

(S45: Second metal layer forming step)
On the other hand, a second metal layer 450 is provided so as to cover at least a portion of the outer periphery of the second power cable 100b and to be spaced apart from the first metal layer 440 with a predetermined spacing section in between in the axial direction of the conductor 110.

(S46: Insulating layer forming step)
After the first metal layer 440 and the second metal layer 450 are provided, one insulating tube that has been released in advance is inserted between the outer periphery of a part of the first metal layer 440 and between the first metal layer 440 and the second metal layer 450. The insulating tube is moved to a position overlapping the outer periphery of the insulating unit 300 exposed in the spaced part of the insulating tube and the outer periphery of a part of the second metal layer 450, and the insulating tube is heat-shrinked. In this way, the outer periphery of a part of the first metal layer 440, the outer periphery of the insulating unit 300 exposed in the space between the first metal layer 440 and the second metal layer 450, and a part of the second metal layer 450 so as to continuously cover the outer circumference of the area. An insulating layer 460 is provided.

At this time, in this embodiment, the insulating layer 460 of the protection part 400 is brought into contact with the separation part SP of the external semiconducting layer 380 of the insulation unit 300, and the separation part SP is covered by the insulating layer 460.

(S47: Third metal layer forming step)
Once the insulating layer 460 is provided, it (continuously) covers the outer periphery of the insulating layer 460 and overlaps the insulating layer 460 above both a portion of the first metal layer 440 and a portion of the second metal layer 450. Thus, the third metal layer 470 is provided.

The subsequent steps are similar to those in the first embodiment.

(3) Summary of this embodiment In this embodiment, the protection unit 400 has two electrically isolated structures: a sandwich structure including a first metal layer 440/insulating layer 460/third metal layer 470, and a second metal layer 470. It has a sandwich structure including layer 450/insulating layer 460/third metal layer 470. That is, the third metal layer 470 overlaps the insulating layer 460 above both a portion of the first metal layer 440 and a portion of the second metal layer 450.

Here, in the above-mentioned modification 1-2, insulation can be improved by stacking a plurality of insulating layers 420. However, it is necessary to pass a plurality of shrinkable insulating tubes through the power cable 100 in advance before the step of forming the insulating layer. This may make the work difficult or take a long time.

Furthermore, in the above-mentioned modification 1-2, the total thickness of the insulating layer 420, which has poorer water-blocking properties than the metal layer, becomes thicker, so that moisture permeation through the insulating layer 420 may easily occur. As a result, there is a possibility that the water-blocking property will be reduced.

In contrast, in this embodiment, the first metal layer 440, the second metal layer 450, and the third metal layer 470 can be insulated by only one insulating layer 460. That is, with only one insulating layer 460, electrical disconnection for two locations can be ensured.

Thereby, it is only necessary to pass one shrinkable insulating tube in advance. That is, the work for forming the insulating layer 460 can be easily performed and the time required for the work can be shortened.

In addition, by using only one insulating layer 420, the thickness of the insulating layer 420, which has poorer water-blocking properties than a metal layer, can be made thinner. Thereby, it is possible to suppress a decrease in water-blocking properties due to the thickness of the insulating layer 420.

As a result, it becomes possible to easily manufacture the cable connection structure 20 and to stably improve both the water-blocking property and the electrical disconnection property.

(4) Modification of Second Embodiment Modification 2-1 of the present embodiment will be described with reference to FIG. 5B.

<Modification 2-1>
As shown in FIG. 5B, in Modification 2-1, the end of the insulating layer 460 in the axial direction of the conductor 110 coincides with the end of the third metal layer 470, for example. Even in modification 2-1, the effects of the second embodiment can be obtained.

<Other embodiments of the present disclosure>
Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above-described embodiments, and various changes can be made without departing from the gist thereof.

In the above-described embodiment, one cable connection structure 20 that the connected power cables 10 have has been described, but the connected power cables 10 may have a plurality of cable connection structures 20.

In the embodiment described above, a case has been described in which the cable connection structure 20 is applied to three-phase alternating current, but the cable connection structure 20 may also be applied to direct current.

In the above-described embodiment, a case has been described in which the outer semiconducting layer 380 has one separation part SP, but the outer semiconducting layer 380 may have, for example, two separation parts SP. In this case, of the two isolation parts SP, the first isolation part SP is in contact with the insulating layer 420 of the protection part 400 and is covered by the insulating layer 420. That is, electrical disconnection of the first separation part SP is ensured. On the other hand, a copper mesh tape is wrapped over the second separation part SP, and the external semiconducting layer 380 is connected to the second separation part SP with the second separation part SP in between.

In the above-described embodiment, the insulating layer 420 or 460 includes a heat-shrinkable insulating tube or an insulating tape. It may also be configured in combination with tape.

Each of the first metal layer 410 and second metal layer 430 in the above-described first embodiment, and the first metal layer 440, second metal layer 450, and third metal layer 470 in the above-described second embodiment are made of a metal sheet. Although a case has been described in which each metal layer of the present disclosure is made of metal only. Each metal layer may have a resin layer on at least one of the front and back surfaces of the metal sheet. Furthermore, each metal layer may be configured such that the metal sheet having the resin layer can be closed with a zipper. Furthermore, each metal layer may have an adhesive layer on at least one of the front and back surfaces of the metal sheet.

The first metal layer 410 and the second metal layer 430 in the first embodiment described above, and the first metal layer 440, second metal layer 450 and third metal layer 470 in the second embodiment described above are the same as each other. Although the case where metal (aluminum) is included has been described, the present disclosure is not limited to this case. These metal layers may have different metals. However, from the viewpoint of suppressing electrolytic corrosion, it is better for these metal layers to have the same metal.

In the second embodiment described above, the configuration shown in FIG. 4 is illustrated as the protection unit 400, but the present disclosure is not limited to this case. The first metal layer 440 may be provided, for example, so as to cover only a portion of the outer periphery of the first power cable 100a. On the other hand, the second metal layer 450 may be provided so as to continuously cover a portion of the outer periphery of the second power cable 100b and the outer periphery of the insulation unit 300 in a region close to the second power cable 100b.

<Additional notes>
Aspects of the present disclosure will be additionally described below.

(Additional note 1)
a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
an insulating layer provided so as to continuously cover an outer periphery of the insulating unit exposed from the first metal layer and a part of the outer periphery of the first metal layer;
The insulating layer is provided so as to continuously cover a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and is provided above a part of the first metal layer. a second metal layer overlapping the layer;
has
The second metal layer is insulated from the first metal layer by the insulating layer. Cable connection structure.

(Additional note 2)
The cable connection structure according to appendix 1, wherein the insulating layer extends outward from the end of the second metal layer in the axial direction of the conductor.

(Additional note 3)
a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided to cover at least a portion of the outer periphery of the first power cable;
a second metal layer provided to cover at least a portion of the outer periphery of the second power cable and spaced apart from the first metal layer across a predetermined space in the axial direction of the conductor;
an insulating layer provided so as to continuously cover a part of the outer periphery of the first metal layer, an outer periphery of the insulating unit exposed in the separation part, and a part of the outer periphery of the second metal layer;
a third metal layer provided to cover the outer periphery of the insulating layer and overlapping the insulating layer above both a portion of the first metal layer and a portion of the second metal layer;
has
The third metal layer is insulated from the first metal layer and the second metal layer by the insulating layer. Cable connection structure.

(Additional note 4)
The cable connection structure according to appendix 3, wherein the insulating layer extends outward from the end of the third metal layer in the axial direction of the conductor.

(Appendix 5)
The insulation unit is
an inner semiconducting layer disposed to cover at least the outer periphery of the sleeve and having semiconductivity;
an insulating unit insulating layer that is provided to cover the outer periphery of each of the internal semiconductive layer, a part of the first power cable, and a part of the second power cable, and has an insulating property;
an outer semiconductive layer having semiconductivity and provided so as to cover the outer periphery of each of the insulating layer, a portion of the first power cable, and a portion of the second power cable;
has
The outer semiconducting layer has at least one separation section separated in the axial direction of the first power cable and the second power cable,
The cable connection structure according to any one of Supplementary Notes 1 to 4, wherein the insulating layer of the protection part covers the separation part of the insulation unit while being in contact with the separation part.

(Appendix 6)
The cable connection structure according to any one of Supplementary Notes 1 to 5, wherein the insulating layer is laminated in plurality.

(Appendix 7)
The first metal layer is
a first metal shielding layer comprising a metal mesh tape;
a first metal water-blocking layer including a metal sheet;
The cable connection structure according to any one of Supplementary notes 1 to 6.

(Appendix 8)
The second metal layer is
a second metal shielding layer comprising a metal mesh tape;
a second metal water-blocking layer including a metal sheet;
The cable connection structure according to any one of Supplementary Notes 1 to 7.

(Appendix 9)
A connected power cable comprising at least one cable connection structure according to any one of appendices 1 to 8.

(Appendix 10)
providing a first power cable and a second power cable each having a conductor;
connecting the conductor of the first power cable and the conductor of the second power cable with a cylindrical sleeve;
providing an insulating unit that maintains insulation around the sleeve so as to cover the outer periphery of the sleeve;
providing a protective portion to protect the outside of the insulation unit, a portion of the first power cable, and a portion of the second power cable;
has
The step of providing the protection portion includes:
providing a first metal layer so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
providing an insulating layer so as to continuously cover the outer periphery of the insulating unit exposed from the first metal layer and the outer periphery of a part of the first metal layer;
Continuously covers a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and overlaps the insulating layer above a part of the first metal layer. a step of providing a second metal layer,
has
In the step of providing the second metal layer,
A method for manufacturing a cable connection structure, wherein the second metal layer is insulated from the first metal layer by the insulating layer.

(Appendix 11)
providing a first power cable and a second power cable each having a conductor;
connecting the conductor of the first power cable and the conductor of the second power cable with a cylindrical sleeve;
providing an insulating unit that maintains insulation around the sleeve so as to cover the outer periphery of the sleeve;
providing a protective portion to protect the outside of the insulation unit, a portion of the first power cable, and a portion of the second power cable;
has
The step of providing the protection portion includes:
providing a first metal layer so as to cover at least a portion of the outer periphery of the first power cable;
providing a second metal layer so as to cover at least a portion of the outer periphery of the second power cable and to be spaced apart from the first metal layer across a predetermined space in the axial direction of the conductor;
providing an insulating layer so as to continuously cover a part of the outer periphery of the first metal layer, a part of the outer periphery of the insulating unit exposed in the spaced part, and a part of the second metal layer;
providing a third metal layer so as to cover the outer periphery of the insulating layer and overlap the insulating layer above both a portion of the first metal layer and a portion of the second metal layer;
has
In the step of providing the third metal layer,
A method for manufacturing a cable connection structure, wherein the third metal layer is insulated from the first metal layer and the second metal layer by the insulating layer.

10 Connected power cables 20 Cable connection structure 100 Power cable 100a First power cable 100b Second power cable 110 Conductor 112 Conductor strand 114 Conductor strand layer 120 Cable internal semiconducting layer 130 Cable insulating layer 140 Cable external semiconducting layer 150 Cable metal shielding layer 160 Cable sheath 200 Sleeve 300 Insulation unit 320 Inner semiconducting layer 340 Insulating unit insulating layer 360 Stress cone portion 380 Outer semiconducting layer 400 Protective portion 410 First metal layer 420 Insulating layer 430 Second metal layer 440 1 metal layer 450 2nd metal layer 460 Insulating layer 470 3rd metal layer 490 Outermost insulating layer SP Separation part

Claims (7)

a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
an insulating layer provided so as to continuously cover an outer periphery of the insulating unit exposed from the first metal layer and a part of the outer periphery of the first metal layer;
The insulating layer is provided so as to continuously cover a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and is provided above a part of the first metal layer. a second metal layer overlapping the layer;
has
The second metal layer is insulated from the first metal layer by the insulating layer. Cable connection structure. a first power cable and a second power cable each having a conductor;
a cylindrical sleeve connecting the conductor of the first power cable and the conductor of the second power cable;
an insulating unit provided to cover the outer periphery of the sleeve and maintain insulation around the sleeve;
a protection part that protects the outside of the insulation unit, a part of the first power cable, and a part of the second power cable;
has
The protection part is
a first metal layer provided to cover at least a portion of the outer periphery of the first power cable;
a second metal layer provided to cover at least a portion of the outer periphery of the second power cable and spaced apart from the first metal layer across a predetermined space in the axial direction of the conductor;
an insulating layer provided so as to continuously cover a part of the outer periphery of the first metal layer, an outer periphery of the insulating unit exposed in the separation part, and a part of the outer periphery of the second metal layer;
a third metal layer provided to cover the outer periphery of the insulating layer and overlapping the insulating layer above both a portion of the first metal layer and a portion of the second metal layer;
has
The third metal layer is insulated from the first metal layer and the second metal layer by the insulating layer. Cable connection structure. The insulation unit is
an inner semiconducting layer disposed to cover at least the outer periphery of the sleeve and having semiconductivity;
an insulating unit insulating layer that is provided to cover the outer periphery of each of the internal semiconductive layer, a part of the first power cable, and a part of the second power cable, and has an insulating property;
an outer semiconductive layer having semiconductivity and provided so as to cover the outer periphery of each of the insulating layer, a portion of the first power cable, and a portion of the second power cable;
has
The outer semiconducting layer has at least one separation section separated in the axial direction of the first power cable and the second power cable,
The cable connection structure according to claim 1 or 2, wherein the insulating layer of the protection part covers the separation part of the insulation unit while being in contact with the separation part. The cable connection structure according to claim 1 or 2, wherein the insulating layer is laminated in plurality. A power cable comprising at least one cable connection structure according to claim 1 or 2 and connected together. providing a first power cable and a second power cable each having a conductor;
connecting the conductor of the first power cable and the conductor of the second power cable with a cylindrical sleeve;
providing an insulating unit that maintains insulation around the sleeve so as to cover the outer periphery of the sleeve;
providing a protective portion to protect the outside of the insulation unit, a portion of the first power cable, and a portion of the second power cable;
has
The step of providing the protection portion includes:
providing a first metal layer so as to continuously cover a portion of the outer periphery of the first power cable and the outer periphery of the insulation unit in a region close to the first power cable;
providing an insulating layer so as to continuously cover the outer periphery of the insulating unit exposed from the first metal layer and the outer periphery of a part of the first metal layer;
Continuously covers a part of the outer periphery of the second power cable and the outer periphery of the insulating layer in a region close to the second power cable, and overlaps the insulating layer above a part of the first metal layer. a step of providing a second metal layer,
has
In the step of providing the second metal layer,
A method for manufacturing a cable connection structure, wherein the second metal layer is insulated from the first metal layer by the insulating layer. providing a first power cable and a second power cable each having a conductor;
connecting the conductor of the first power cable and the conductor of the second power cable with a cylindrical sleeve;
providing an insulating unit that maintains insulation around the sleeve so as to cover the outer periphery of the sleeve;
providing a protective portion to protect the outside of the insulation unit, a portion of the first power cable, and a portion of the second power cable;
has
The step of providing the protection portion includes:
providing a first metal layer so as to cover at least a portion of the outer periphery of the first power cable;
providing a second metal layer so as to cover at least a portion of the outer periphery of the second power cable and to be spaced apart from the first metal layer across a predetermined space in the axial direction of the conductor;
providing an insulating layer so as to continuously cover a part of the outer periphery of the first metal layer, a part of the outer periphery of the insulating unit exposed in the spaced part, and a part of the second metal layer;
providing a third metal layer so as to cover the outer periphery of the insulating layer and overlap the insulating layer above both a portion of the first metal layer and a portion of the second metal layer;
has
In the step of providing the third metal layer,
A method for manufacturing a cable connection structure, wherein the third metal layer is insulated from the first metal layer and the second metal layer by the insulating layer.