KR20210120368A - Connecting Structure of Power Cable Conductor And Connecting Box Of Power Cable Using The Same - Google Patents

Abstract

The present invention relates to a conductor connection structure that omits a corona shield in an intermediate connection box of a power cable and sufficiently secures thickness of a sleeve member fastened to the conductor with a fractured bolt to secure fastening force between the sleeve member and the conductor of the power cable, thereby preventing an insulation layer of the power cable shrinking back and improving workability of intermediate connection work of the power cable.

Description

Connecting Structure of Power Cable Conductor And Connecting Box Of Power Cable Using The Same

The present invention relates to a conductor connection structure of a power cable. More specifically, the present invention omits the corona shield in the intermediate junction box of the power cable, and sufficiently secures the thickness of the sleeve member fastened to the conductor with the breaking bolt to sufficiently secure the fastening force between the sleeve member and the conductor of the power cable. It relates to a conductor connection structure of a power cable that can prevent shrink back of the insulation layer of the power cable and improve the workability of the intermediate connection operation of the power cable.

The power cable may be connected at a predetermined length interval to build a long-distance power grid, and may supply power to a power demanding destination after transformation or distribution through termination.

In the case of intermediate connection of these power cables, the conductors of both power cables to be connected may be connected by a method such as crimping or welding using a sleeve member.

As a conductor of the power cable, a copper (Cu) conductor or an aluminum (Al) metal material may be used as a conductor, and an aggregate conductor in which a plurality of wires are combined for bending characteristics, etc. may be used.

In the case of an aggregate conductor constructed by assembling copper (CU) material wires according to the prior art, the insulating layer of each wire constituting the aggregate conductor is removed, assembled again, inserted into a sleeve member, and connected using a compression method, and aluminum (AL) In the case of an aggregated conductor composed of bare wires, the conductor connection is performed by welding after separating all the plurality of strands of aluminum (Al) material constituting the aggregated conductor and removing the watertight paper tape or compound between them. became

All conductor connection methods such as compression or welding using a sleeve member have problems in that potential quality risks increase due to scattering of conductive materials in the process of removing the insulating layer of the wires constituting the conductor, and the working time is long and the cost is high.

Recently, the conductor of the power cable is connected using a sleeve member, but without crimping or welding the conductor of the power cable, a fastening hole is formed in the sleeve member, and the sleeve member and the conductor of the power cable are fastened using a breaking bolt. A method has been introduced.

The breaking bolt is fastened to the sleeve member, and by plastically deforming the assembly conductor composed of the bare wire, an energization path including the conductor, the breaking bolt, and the sleeve member may be formed.

In the case of connecting a conductor using a breaking bolt and a sleeve member, the compression/welding process is omitted, but in order to secure sufficient fastening force between the conductor and the sleeve member, the thickness of the sleeve member configured in the form of a pipe must be sufficiently secured.

However, for the connection of the power cable having the XLPE insulation layer, the intermediate junction box to which the sleeve member is applied is a conductor connection between the sleeve member constituting the conductor connection structure and the high voltage electrode constituting the joint sleeve (PMJ, pre-molded joint). Since the corona shield surrounding the structure is used, considering the thickness of the corona shield, the thickness of the sleeve member accommodated therein is not sufficiently secured, and even considering the structure in which the corona shield is omitted, the insulation layer shrinks (shierink back) A separate method is required to prevent

The present invention omits the corona shield in the intermediate junction box of the power cable, and secures the thickness of the sleeve member fastened to the conductor with the breaking bolt sufficiently to secure sufficient fastening force between the sleeve member and the conductor of the power cable and at the same time to insulate the power cable It is a problem to be solved to provide a conductor connection structure of a power cable that can prevent layer shrinkage and improve the workability of the intermediate connection operation of the power cable.

In order to solve the above problems, the present invention provides a conductor connection structure of a power cable for connecting a conductor portion of a power cable having a conductor, an inner semiconducting layer, an insulating layer made of a crosslinked polyethylene material, and an outer semiconducting layer, a pair of electric power bare conductors stripped from the cable; a sleeve member in the form of a pipe having a connection part into which a pair of conductors of the power cable are inserted and a plurality of fastening holes at both ends in the longitudinal direction; and a fixing bolt fastened to the fastening hole of the sleeve member to fix the conductors respectively inserted into the connection parts of the sleeve member. and a cover member mounted while closing a boundary region between the sleeve member and the insulating layer.

In addition, the cover member may be configured in the shape of a pipe having a length smaller than an inner diameter.

In this case, the cover member may be divided into a first cover and a second cover.

In addition, the first cover and the second cover may be fastened with a fastening member in an assembled state.

Here, the inner circumferential surface of both ends of the cover member, the insulating layer of the power cable, and the outer circumferential surface of the end of the sleeve member may be provided with fixing means for engaging and fixing.

In addition, the fixing means may be a protrusion formed on the inner peripheral surface of both ends of the cover member, the insulating layer of the power cable, and a groove formed on the outer peripheral surface of the end of the sleeve member.

In addition, the fixing protrusions formed on the inner peripheral surfaces of both ends of the cover member, the insulating layer of the power cable, and the fixing grooves formed on the outer peripheral surfaces of the ends of the sleeve member may be continuously formed in the circumferential direction.

In addition, outer diameters of the insulating layer, the cover member, and the sleeve member constituting the conductor connection structure of the power cable may be the same.

In this case, a partition wall may be provided in an inner central region of the sleeve member, and a plurality of fastening holes to which the plurality of fixing bolts are fastened may be dispersed in regions other than the central region.

In addition, the fixing bolt may be a breaking bolt that is separated by breaking the head when a torque greater than or equal to a predetermined size is applied.

Here, the sleeve member may be made of copper, a copper alloy, tin-plated copper, or a tin-plated copper alloy material.

In addition, the fixing bolt may be made of brass or a brass alloy material.

In addition, in order to solve the above problems, the present invention is a power cable conductor connection structure described above; A high-voltage electrode in contact with a sleeve member constituting the conductor connection structure of the power cable, a pair of shielding electrodes in contact with the outer semiconducting layer of the power cable, and the high-voltage electrode, the insulating layer of the power cable, and the shielding electrode a joint sleeve comprising an enclosing sleeve insulation layer; And, it is possible to provide a pair of power cables, an intermediate junction box of the power cables including a housing surrounding the joint sleeve.

According to the conductor connection structure of the power cable according to the present invention, since the conductor and the sleeve member of the power cable are fastened with the breaking bolt, the insulation removal process of the insulated wire can be omitted, so that the workability of the conductor connection operation can be improved. .

In addition, according to the conductor connection structure of the power cable according to the present invention, it is not necessary to apply the corona shield constituting the conductor connection structure of the power cable. can be tightened sufficiently.

In addition, according to the conductor connection structure of the power cable according to the present invention, even if the corona shield constituting the conductor connection structure of the power cable is omitted, the boundary region between the insulating layer and the sleeve member of the power cable is closed, and the insulating layer of the power cable and the By applying the cover member for locking the sleeve member, it is possible to improve workability when the joint sleeve is installed and to prevent or alleviate the shrinkage of the insulation layer that occurs when the conductor of the power cable is energized.

Figure 1 shows a multi-stage stripped perspective view of the power cable of the present invention.
2 shows an embodiment of a sleeve member provided in the conductor connection structure of the power cable according to the present invention, and FIG. 3 shows a cross-sectional view of the sleeve member shown in FIG.
4 and 5 show a side view and a cross-sectional view of a conductor connection structure of a power cable according to the present invention.
6 to 11 show the assembly process of the conductor connection structure of the power cable according to the present invention.
12 is a cross-sectional view of an intermediate junction box having a conductor connection structure of a power cable according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed subject matter may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art. Like reference numerals refer to like elements throughout.

Figure 1 shows a multi-stage stripped perspective view of the power cable of the present invention.

Referring to FIG. 1 , the power cable 100 includes a conductor 11 , an inner semiconducting layer 12 , a cable insulating layer 14 , and an outer semiconducting layer 16 in the cable length direction along the conductor 11 . A cable core unit 10 for transmitting electric power only to and preventing current from leaking in the radial direction of the cable is provided.

The conductor 11 serves as a passage through which electric current flows to transmit power, and has excellent conductivity to minimize power loss, and a material having strength and flexibility suitable for cable manufacturing and use, for example, copper or aluminum, etc. can be made with

As shown in FIG. 1 , the conductor 11 may be configured as an aggregate conductor in which a plurality of strands are grouped and twisted, respectively. Although the aggregate conductor shown in FIG. 1 constitutes the aggregated conductor of the 1+6 structure, the method of configuring the aggregated conductor as the conductor may be composed of various combinations such as 4 division, 5 division, and 1+N division.

Since the conductor is formed by twisting a plurality of wires, the surface thereof is not smooth, and thus an electric field may be non-uniform, and partial corona discharge is likely to occur. In addition, when a void is formed between the surface of the conductor 11 and the cable insulating layer 14 to be described later, the insulating performance may be deteriorated.

In order to solve the above problems, an inner semiconducting layer 12 may be formed outside the conductor 11 . The inner semiconducting layer 12 may have semiconductivity by adding conductive particles such as carbon black, carbon nanotubes, carbon nanoplates, and graphite to an insulating material.

The inner semiconducting layer 12 prevents an abrupt electric field change from occurring between the conductor 11 and the cable insulation layer 14 to be described later, thereby stabilizing insulation performance. In addition, the electric field is made uniform by suppressing the non-uniform charge distribution on the surface of the conductor 11, and a gap is prevented from being formed between the conductor 11 and the cable insulation layer 14 to suppress corona discharge, insulation breakdown, etc. will play a role.

The cable insulating layer 14 is provided on the outside of the inner semiconducting layer 12 to electrically insulate it from the outside so that the current flowing along the conductor 11 does not leak to the outside.

The insulating layer 14 is composed of an insulating composition having high breakdown voltage, stable insulating performance for a long period of time, low dielectric loss and resistance to heat such as heat resistance, and the insulating composition is made of polyethylene and poly A polyolefin resin such as propylene, preferably a resin based on a polyethylene resin, in particular, cross-linked polyEthyline (XLPE) can be used.

In addition, the insulating composition may include inorganic nanoparticles or an organic polar material. The inorganic nanoparticles or organic polar materials are injected from the conductor 11 into the insulating layer 14 when the power cable is energized, or a space charge formed by by-products generated when the insulating layer 14 is cross-linked. ) by trapping the space charge, the electric field strength in the vicinity of the conductor is increased, thereby suppressing a decrease in the overlapping impulse breaking strength of the insulating layer.

In addition, the insulating composition may further include other additives such as a crosslinking agent, an antioxidant, and a scorch inhibitor in addition to the inorganic nanoparticles. The crosslinking agent may be different depending on a crosslinking method of the insulating composition, and may include, for example, an organic peroxide such as dicumyl peroxide during chemical crosslinking. The antioxidant functions to suppress deterioration due to oxidation of the insulating layer formed from the insulating composition, and may include, for example, phenol-based, quinone-based, and amine-based antioxidants. The scorch inhibitor performs a function of additionally securing crosslinking properties during crosslinking of the insulating composition and suppressing scorch due to long-term extrusion.

The insulating layer 14 may be formed by extruding the insulating composition, and by extruding together with the inner semiconducting layer and the outer semiconducting layer 16 to be described later, the insulating layer and the inner semiconducting layer to the outer semiconducting layer 16 It is possible to prevent voids or foreign substances from entering the interface.

An outer semiconducting layer 16 may be provided outside the cable insulating layer 14 . The outer semiconducting layer 16 is formed of a material having semiconductivity by adding conductive particles, for example, carbon black, carbon nanotubes, carbon nanoplates, graphite, etc., to an insulating material like the inner semiconducting layer, so as to insulate the cable The insulating performance is stabilized by suppressing non-uniform charge distribution between the layer 14 and the metal sheath 22 to be described later. In addition, the outer semiconducting layer 16 smoothes the surface of the cable insulation layer 14 in the cable to relieve electric field concentration to prevent corona discharge, and to physically protect the cable insulation layer 14 can be done

A cable protection unit 20 is provided on the outside of the cable core unit 10 , and the power cable 100 installed on the seabed may additionally include a cable sheath unit 30 . The cable protection unit and the cable sheath unit protect the core unit from various environmental factors such as moisture penetration, mechanical trauma, and corrosion that may affect the power transmission performance of the cable.

A moisture absorbing part 21 that may be provided outside the outer semiconducting layer 16 may be additionally provided. The moisture absorbing part may be formed between the stranded strands of the conductor 11 and/or outside the conductor 11, and has a high rate of absorbing moisture penetrating into the cable and excellent ability to maintain an absorption state. It is composed of powder, tape, coating layer, or film containing super absorbent polymer (SAP), and serves to prevent moisture from penetrating in the longitudinal direction of the cable. In addition, the moisture absorbing part may have semi-conductivity to prevent abrupt electric field change.

The cable protection unit 20 includes a metal sheath 22 and a polymer sheath 24 on the outside of the moisture absorption unit 21 to protect the cable from a fault current, external force, or other external environmental factors.

The metal sheath 22 may be formed to surround the core part 10 . In particular, when the power cable 100 is installed in an environment such as the seabed, it can be formed to seal the cable core part 10 to prevent foreign substances such as moisture from entering the cable core part 10 . In addition, by extruding the molten metal to the outside of the cable core part 10 to have a seamless and continuous outer surface, it is possible to have excellent water-repellent performance. Lead or aluminum is used as the metal, and in the case of the power cable 100 installed on the seabed, it is preferable to use lead with excellent corrosion resistance to seawater, and a metal element is added to supplement the mechanical properties. It is more preferable to use one lead alloy.

In addition, the metal sheath 22 is grounded at the end of the power cable 100 to serve as a path through which an accident current flows when an accident such as a ground fault or short circuit occurs, protects the cable from external impact, and discharges an electric field to the outside of the cable can prevent it from happening.

In addition, the metal sheath 22 may be coated with an anti-corrosion compound, for example, blown asphalt, etc. on the surface of the metal sheath 22 to further improve corrosion resistance, water resistance, etc. of the cable and to improve adhesion with the polymer sheath 24. can

In addition, a copper wire straight-through tape or a moisture absorbing layer 21 may be additionally provided between the metal sheath 22 and the cable core part 10 . The copper wire straight-in tape is composed of a copper wire and a non-woven tape, etc., and functions to facilitate electrical contact between the outer semiconducting layer 16 and the metal sheath 22, and the moisture absorption layer 21 penetrates the cable. It is composed of powder, tape, coating layer or film containing super absorbent polymer (SAP), which absorbs moisture quickly and has excellent ability to maintain absorption, so that moisture penetrates in the longitudinal direction of the cable. serves to prevent In addition, the copper wire straight-through tape and the moisture absorbing layer 21 preferably have semi-conductive properties to prevent a sudden electric field change, and may be configured by including a copper wire in the moisture absorbing layer so as to perform both conduction and moisture absorption functions. .

The polymer sheath 24 is formed on the outside of the metal sheath 22 to improve corrosion resistance and water resistance of the cable, and to protect the cable from mechanical trauma and other external environmental factors such as heat and ultraviolet rays. can The polymer sheath 24 may be formed of a resin such as polyvinyl chloride (PVC), polyethylene, etc., and in the case of the power cable 100 to be laid on the seabed, it is preferable to use a polyethylene resin having excellent water resistance, and flame retardancy. In this demanding environment, it is preferable to use a polyvinyl chloride resin.

The power cable 100 is provided with a metal steel strip 26 made of galvanized steel tape or the like on the outside of the polymer sheath 24, and the metal sheath 22 is expanded by the expansion of the insulating oil. can be prevented from doing In addition, a bedding layer (not shown) made of a semi-conductive non-woven tape or the like and buffering an external force applied to the power cable 100 may be provided on the upper and/or lower portion of the metal steel strip layer 26 , and polyvinyl chloride to further improve the corrosion resistance, water resistance, etc. of the power cable 100 by further providing an external sheath 28 made of a resin such as polyethylene, and additionally protect the cable from mechanical trauma and other external environmental factors such as heat and ultraviolet rays can do.

In addition, the submarine power cable laid on the seabed is easily injured by the anchor of a ship, and may be damaged by bending force caused by ocean currents or waves, frictional force with the seabed, etc. An exterior part (not shown) may be additionally provided.

Such a power cable is manufactured in units of a certain length, wound on a bobbin, etc. and provided to the installation site so that the intermediate connection is performed through the intermediate junction box, or the terminal connection is performed through the terminal junction box to construct a power grid.

Hereinafter, the conductor bundle structure of the power cable in the intermediate junction box and the terminal junction box will be described in detail.

FIG. 2 shows one embodiment of the sleeve member 200 provided in the conductor connection structure of the power cable according to the present invention, and FIG. 3 shows a cross-sectional view of the sleeve member 200 shown in FIG.

In order to connect the power cable, the end of the power cable is stripped so that the conductor and the insulator are exposed, and the sleeve member 200 for inserting and connecting the stripped conductor is provided.

As a method of connecting the conductors of the power cable, there are a method of using the sleeve member 200 and a method of welding both conductors, but in consideration of workability, etc., a pair of conductors 10a of the power cable to the sleeve member 200, The conductor connection structure may be configured by inserting and mounting 10b) and pressing the sleeve member 200 on which the conductor is mounted.

The sleeve member 200 may be configured in the form of a pipe, and a connection portion 210 capable of inserting a conductor in the opposite direction is provided at both ends. In addition, a partition wall 250 is provided at the inner center of the sleeve member 200 to determine a conductor insertion position or limit, and to allow the partition wall 250 to be in electrical contact with the end surfaces of both conductors to provide a sufficient energization path. It can be configured to secure.

The sleeve member 200 may be made of copper, a copper alloy, tin-plated copper, or a tin-plated material having good conductivity.

In addition, the sleeve member 200 constituting the conductor connection structure according to the present invention may be provided with a plurality of fastening holes 230 for fastening the plurality of fixing bolts 330 .

The partition wall 250 described above may be provided in an inner central region of the sleeve member 200 , and the plurality of fastening holes 230 to which the plurality of fixing bolts 330 are fastened are distributed in regions other than the central region. can be formed. In addition, the fastening hole 230 formed in the sleeve member 200 may have a screw thread for fastening the fixing bolt 330 may be formed on the inner circumferential surface.

And, the outer circumferential surface of the end of the sleeve member 200 may be provided with a fixing means for engaging and fixing the cover member 50 to be described later, and the fixing means includes fixing protrusions formed on the inner circumferential surface of both ends of the cover member 50 to be described later. It may be a fixing groove 215 formed on the outer peripheral surface of both ends of the sleeve member 200, and further, as shown in FIGS. 2 and 3, the fixing groove 215 as the fixing means is continuously formed in the circumferential direction. can be

4 and 5 show a side view and a cross-sectional view of the conductor connection structure 1 according to the present invention.

The present invention provides a conductor connection structure (1) of a power cable for connecting a conductor part of a power cable having a conductor, an inner semiconducting layer, an insulating layer made of Cross-Linked PolyEthyline (XLPE) material, and an outer semiconducting layer And, the conductor connection structure (1) of the power cable is exposed conductors (10a, 10b) stripped from a pair of power cables; a sleeve member 200 in the form of a pipe having a connection part 210 into which a pair of conductors 10a and 10b of the power cable are inserted and a plurality of fastening holes 230 at both ends in the longitudinal direction; a fixing bolt 330 fastened to the fastening hole 230 of the sleeve member 200 in order to fix the conductors respectively inserted into the connection part 210 of the sleeve member 200 ; and a cover member 50 mounted while closing the boundary region between the sleeve member 200 and the insulating layer.

When the conductor connection structure 1 of the power cable according to the present invention is mounted in the intermediate junction box, the corona shield mounted between the joint sleeve and the conductor connection structure 1 may be omitted.

In the conventional conductor connection structure, the corona shield is mounted to surround the sleeve member 200, the corona shield is connected to the sleeve member 200 with a metal wire, etc. to form an equipotential, and the corona shield is a high-voltage electrode ( 430), a joint sleeve was mounted on the conductor connection structure (1).

Therefore, the finish of the conductor connection structure 1 of the power cable was composed of a corona shield, and the outer diameter of the corona shield and the outer diameter of the insulating layer of the power cable were the same.

The present invention is a method of connecting the conductor and the sleeve member 200 by plastically deforming the conductor using a fixing bolt 330 in the form of a breaking bolt, not by compression, to fasten the sleeve member 200, and the fixing bolt 330 ) and the sleeve member 200 with sufficient fastening force, it is preferable that the thickness of the sleeve member 200 is sufficiently secured. However, since it is necessary to reduce the thickness of the sleeve member 200 by the thickness of the corona shield having an outer diameter equal to the outer diameter of the insulating layer in order to mount the corona shield as described above, the sleeve is fastened to the conductor using a breaking bolt or the like. The thickness of the member 200 may be insufficient.

Therefore, the present invention does not use the conventional corona shield, but applies a structure in which the sleeve member 200 and the high-voltage electrode of the joint sleeve to be described below are in direct contact, so that the thickness of the sleeve member 200 is reduced by the thickness of the corona shield. Sufficient fastening force may be provided when the sleeve member 200 and the conductor are reinforced and fastened with a fixing bolt in the form of a breaking bolt.

In addition, the fixing bolt 330 is made of brass or a brass alloy material and may be used as a energization path in a state in which the fastening is completed in a state in which the fastening is completed.

Since the present invention omits the corona shield in the conductor connection structure (1) of the power cable and the sleeve member 200 is in direct contact with the joint sleeve to be described later, as shown in FIG. 4, the present invention is the conductor of the power cable The outer diameter of the sleeve member 200 of the connection structure 1 and the outer diameter of the insulating layer of the power cable may be configured to be the same.

As shown in FIG. 5 , the fixing bolt 330 is fastened to the sleeve member 200 , digging into the conductor therein and plastically deforming the conductor, and at the same time firmly fastening the conductor and the sleeve member 200 . It is possible to form a conduction path through the conductor and the sleeve member 200 without removing the wire insulation.

Therefore, it is possible to improve the tensile strength of the conductor connection structure according to the expansion and contraction of the conductor rather than the method of connecting the conductor and the sleeve member by a method such as crimping, and the electrical connection performance through the fixing bolt 330 fastened by digging into the conductor It can be shaped and the operation of removing the insulation of the wire constituting the conductor is also omitted, so that the workability of the conductor connection operation can be improved.

As described above, although the coupling of the conductor and the sleeve member 200 is performed through the fixing bolt 330 , it is necessary to prepare for the shrink back phenomenon of the insulation layer of the power cable that occurs when the conductor is energized.

In the case of the conventionally applied corona shield, it is mounted on the outside of the sleeve member of the conductor connection structure and clamps the end of the insulating layer at the same time to prevent or alleviate the shrinkage of the insulating layer. (50) Apply the cover member (50) to the conductor connection structure of the power cable. The cover member 50 may close the boundary region between the sleeve member 200 and the insulating layer, and may be mounted while fixing the sleeve member and the insulating layer. The cover member 50 is configured in the shape of a pipe having a length smaller than an inner diameter to fasten both ends of the insulating layer and the sleeve member 200 together. A detailed description of the cover member 50 is postponed.

6 to 11 show the assembly process of the conductor connection structure of the power cable according to the present invention.

6 and 7, in order to configure the conductor connection structure of the power cable according to the present invention, the connection parts 210 at both ends of the sleeve member 200 in the form of a pipe having a plurality of fastening holes 230 are provided. ) and insert the conductors (10a, 10b) of a pair of power cables.

Each of the conductors 10a and 10b of the power cable may be inserted up to the partition wall 250 having an end in the central region of the sleeve member 200 .

When the respective conductors 10a and 10b are inserted into the connection portion 210 of the sleeve member 200 , as shown in FIG. 8 , bolts for fixing to all the fastening holes 230 formed in the sleeve member 200 . When the 330 is mounted, and each fixing bolt 330 is fastened so that the head of the fixing bolt 330 is broken as shown in FIG. 9 , the lower region of each fixing bolt 330 is a power cable It is integrated with the conductor by digging into the conductor of the conductor and plastically deforming the conductor, and the upper part is fastened to the sleeve member 200 .

As described above, the fixing bolt 330 may be a breaking bolt in which a head portion is broken and separated when a torque greater than or equal to a predetermined size is applied.

If the thickness of the sleeve member is not sufficient, the upper area may not be supported by the sleeve member while the lower area of the fixing bolt is integrated with the conductor, and the sleeve member may be twisted or damaged.

However, in the present invention, since the corona shield is omitted, the thickness of the sleeve member 200 may be sufficiently increased, thereby improving the coupling force between the sleeve member 200 and the conductor.

And, as shown in FIG. 9 , in a state in which the conductor of the power cable and the sleeve member 200 are fastened with the fixing bolt 330 , the insulation layer of the power cable and the outer diameter of the sleeve member 200 . The same configuration can facilitate the mounting of a joint sleeve, which will be described later.

And, as shown in FIG. 10 , when the connection between the conductor and the sleeve member 200 is completed, the boundary region between the sleeve member 200 and the insulating layer of the power cable may be closed with the cover member 50 .

As described above, the cover member 50 not only closes the boundary area but also prevents the shrinkage of the insulating layer.

As shown in FIG. 10 , the cover member 50 may be configured in a pipe shape with a length smaller than the inner diameter, and the cover member 50 is mounted in a state where the connection between the conductor and the sleeve member 200 is completed. It may be divided into a first cover 50a and a second cover 50b.

In addition, as shown in FIG. 10 , the first cover 50a and the second cover 50b may be fastened to the fastening member 53 in the assembled state to maintain the assembled state.

And, as shown in FIGS. 6 to 10, the inner peripheral surface of both ends of the cover member 50, the insulating layer of the power cable, and the outer peripheral surface of the end of the sleeve member 200 may be provided with a fixing means for engaging and fixing. The fixing means includes fixing protrusions 51 formed on the inner peripheral surfaces of both ends of the cover member 50, insulating layers 14a and 14b of the power cable, and fixing grooves 115 formed on the outer peripheral surfaces of the ends of the sleeve member 200, 215), the fixing protrusions 51 formed on the inner peripheral surfaces of both ends of the cover member 50, the insulating layers 14a and 14b of the power cable, and the fixing grooves 115 and 215 formed on the outer peripheral surfaces of the ends of the sleeve member 200. The cover member 50, which is continuously formed in the circumferential direction to close the boundary region between the sleeve member 200 and the insulating layer, can prevent separation of the insulating layer and the sleeve member 200, thereby preventing or alleviating the shrinkage of the insulating layer. can do.

In addition, when a joint sleeve to be described later is mounted, the outer diameters of the insulating layer 14 , the cover member 50 and the sleeve member 200 may be configured to be the same in order to minimize physical interference in the boundary region of the conductor connection structure. 11, in the state in which the cover member 50 is mounted between the sleeve member 200 and the insulating layer of the power cable, the conductor connection structure of the power cable minimizes the protruding or recessed area. may be of the form.

12 shows a cross-sectional view of an intermediate junction box 200 having a conductor connection structure 1 of a power cable according to the present invention.

The present invention is a power cable conductor connection structure (1) described above; A high-voltage electrode 430 in contact with the sleeve member 200 constituting the conductor connection structure of the power cable, a pair of shielding electrodes 440 in contact with the outer semiconducting layer of the power cable, and the high-voltage electrode 430 a joint sleeve 400 including a sleeve insulating layer 430 surrounding the insulating layers 14a and 14b of the power cable and the shielding electrode 440; And, a pair of power cables, it is possible to provide an intermediate junction box 600 of the power cable including the housing 200 surrounding the joint sleeve.

In the power cable connected to the conductor connection structure (1) of the power cable according to the present invention described above, the insulating layer may be composed of cross-linked polyEthyline (XLPE), etc., and the power cable intermediate connection according to the present invention The box may include a joint sleeve 400 surrounding the conductor connection structure of the power cable.

The joint sleeve 400 may be made of an elastic material that can be contracted at room temperature surrounding the pair of power cables 100A and 100B and the aforementioned conductor connection structure, and may be provided in the form of a pre-molded joint. have.

The joint sleeve 400 is mounted on the outside of the conductor connection structure, and a high-voltage electrode 430 electrically connected to the sleeve member 200 and a pair of shielding electrodes contacting the outer semiconducting layer of the pair of power cables. 440 and a sleeve insulating layer 430 surrounding the high voltage electrode 430 , an insulating layer of the power cable, and the shielding electrode 440 .

The high voltage electrode 430 and the shielding electrode 440 constituting the joint sleeve serve to evenly spread the electric field without being locally concentrated therebetween.

In addition, the high-voltage electrode 430 is made of a semi-conductive material and is electrically connected to the conductor of the power cable through the sleeve member 200 , and the shielding electrode 440 is also made of a semi-conductive material and is the same as that of the power cable. It is mounted to be connected to the outer semiconducting layers 16a and 16b.

Accordingly, the electric field distribution inside the power cable intermediate junction box is distributed along between the high voltage electrode 430 and the shielding electrode 440 . In addition, the high voltage electrode 430, the insulating layers 14a and 14b of the power cable, and the sleeve insulating layer 430 surrounding the shielding electrode 440 are made of an insulating material, and insulate the pair of power cables. It comes into contact with the layers 14a and 14b.

The intermediate junction box 600 according to the present invention may include a housing made of a so-called 'coffin box' or a 'metal casing' surrounding the joint sleeve 400, in which case the A space between the housing 200 and the joint sleeve 400 may be filled with a waterproofing material (not shown) to complete the intermediate junction box.

As described above, according to the conductor connection structure of the power cable according to the present invention and the intermediate connection box having the same, since the conductor of the power cable and the sleeve member are fastened with the breaking bolt, the insulation removal process of the insulated wire can be omitted, so the conductor connection Workability can be improved, and since it is not necessary to apply the corona shield constituting the conductor connection structure of the power cable, the thickness of the sleeve member is sufficiently secured and the power cable and the sleeve member can be fastened with sufficient fastening force using the fixing bolt. Even if the corona shield constituting the conductor connection structure of the power cable is omitted, the boundary area between the insulating layer and the sleeve member of the power cable is closed and the cover member that catches the insulating layer and the sleeve member of the power cable is applied. When the joint sleeve is installed, the workability can be improved and the effect of preventing or alleviating the shrinkage of the insulation layer that occurs when the conductor of the power cable is energized can be obtained.

Although the present specification has been described with reference to preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention as set forth in the claims described below. will be able to carry out Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all of them should be considered to be included in the technical scope of the present invention.

100: power cable
200: sleeve member
10: conductor
14: insulator
50: cover member

Claims (13)

In the conductor connection structure of the power cable for connecting the conductor part of the power cable having a conductor, an inner semiconducting layer, an insulating layer made of a crosslinked polyethylene material, and an outer semiconducting layer,
A conductor stripped from a pair of power cables and exposed;
a sleeve member in the form of a pipe having a connection part into which a pair of conductors of the power cable are inserted and a plurality of fastening holes at both ends in the longitudinal direction; and,
a fixing bolt fastened to the fastening hole of the sleeve member to fix the conductors respectively inserted into the connection parts of the sleeve member; and,
Conductor connection structure of a power cable comprising a; a cover member mounted to close the boundary area between the sleeve member and the insulating layer. According to claim 1,
The cover member is a conductor connection structure of a power cable, characterized in that the length is composed of a pipe shape smaller than the inner diameter. 3. The method of claim 2,
The cover member is a conductor connection structure of a power cable, characterized in that configured by dividing the first cover and the second cover. 4. The method of claim 3,
The conductor connection structure of the power cable, characterized in that the first cover and the second cover are fastened with a fastening member in an assembled state. According to claim 1,
The inner circumferential surface of both ends of the cover member, the insulating layer of the power cable, and the outer circumferential surface of the end of the sleeve member are provided with fixing means for engaging and fixing. 6. The method of claim 5,
The fixing means is a conductor connection structure of a power cable, characterized in that the projections formed on the inner peripheral surface of both ends of the cover member, the insulating layer of the power cable, and a groove formed on the outer peripheral surface of the end of the sleeve member. 7. The method of claim 6,
The fixing protrusion formed on the inner peripheral surface of both ends of the cover member, the insulating layer of the power cable, and the fixing groove formed on the outer peripheral surface of the end of the sleeve member are continuously formed in the circumferential direction. According to claim 1,
The conductor connection structure of the power cable, characterized in that the outer diameters of the insulating layer, the cover member, and the sleeve member constituting the conductor connection structure of the power cable are the same. According to claim 1,
A partition wall is provided in the inner central region of the sleeve member, and the plurality of fastening holes to which the plurality of fixing bolts are fastened are dispersedly formed in an area other than the central portion. According to claim 1,
The fixing bolt is a conductor connection structure of a power cable, characterized in that when a torque greater than or equal to a predetermined size is applied, the head is broken and separated. According to claim 1,
The sleeve member is a conductor connection structure of a power cable, characterized in that the material of copper, copper alloy, tin-plated copper or tin-plated copper alloy material. According to claim 1,
The fixing bolt is a conductor connection structure of the power cable, characterized in that brass or brass alloy material. The power cable conductor connection structure according to any one of claims 1 to 12;
A high-voltage electrode in contact with a sleeve member constituting the conductor connection structure of the power cable, a pair of shielding electrodes in contact with the outer semiconducting layer of the power cable, and the high-voltage electrode, the insulating layer of the power cable, and the shielding electrode a joint sleeve comprising an enclosing sleeve insulation layer; and,
An intermediate junction box of a power cable including a pair of power cables, and a housing surrounding the joint sleeve.

Images