JP2734835B2 - Cable shield insulation type plug-in straight connection - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[Industrial applications]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a linear insulating portion of a plastic-insulated power cable, and more particularly to a plug-in linear connecting portion capable of cutting off a cable shielding layer at the linear connecting portion.

[Prior art]

[0002] In general, a straight-line connection portion of a power cable is designed to have the same performance as the cable including the insulation performance. This is not an exception even in a straight connection portion for a plastic insulated power cable, for example, a CV cable, and is designed to have the same performance as a power cable.

[0003] The straight-line connecting portion of the power cable is roughly classified into three types: a tape winding type, a shrinking tube type, and a plug-in type (also referred to as a prefabricated type). Plug-in straight connections that can ensure uniform insulation performance without becoming the mainstream are becoming mainstream.

FIG. 3 is a sectional view showing the structure of a straight connection portion for a 6600 VCV cable. That is, first, the cable conductors 8 of the left and right power cables 11 to be connected are exposed by stepping off the ends, butted against each other, covered with the compression sleeve 1 and compressed and connected. A sleeve cover 2 made of semiconductive rubber is disposed around the conductor sleeve 1, and an inner semiconductive layer 3 as shown in FIG.
a, an insulating cylinder 3 in which an insulating layer 3b and an external semiconductive layer 3c are integrally formed is disposed. The sleeve cover 2 is a component for making the cable conductor 8 and the compression sleeve 1 have the same electric potential as that of the internal semiconductive layer 3a of the insulating cylinder 3, and a voltage is applied between the internal semiconductive layer 3a and the external. Semiconductive layer 3c
To happen between. Around the cable insulator 9, a spacer 4 formed of insulating rubber which fills a gap with the insulating cylinder 3 and plays a role of reinforcing insulation is arranged. When the semiconductive tape 5 is wrapped around the end of the spacer 4 from the cable shielding layer 10 to the outer semiconductive layer 3c of the insulating tube 3, when the cable shielding layer 10 and the semiconductive layer 3c are made to have the same electric potential. It has a tapered shape so that the electric field at the rising portion of the cable shielding layer 10 is reduced.

At this time, it is standard work to wind up the semiconductive tape 5 to the tapered portion 3d of the insulating tube 3. As a result, the cable shielding layers 10 of the left and right power cables 11 are electrically connected, but in order to further allow a current to flow in the event of a ground fault, the tinned soft copper wire 6 is wound around the entire connection portion, and the cable shielding is performed. It is connected to the layer 10. Furthermore, a waterproof tape 7 is wound on the connection from the connection to the cable sheath,
Prevents water from entering the connection.

FIG. 5 is a schematic diagram showing a case where the plug-in type straight connection portion shown in FIG. 3 is applied to a cable line. This line condition is in the middle of the cable termination part 12 at the points A and F, B, C,
D and E show the case where there are straight connection parts at four places,
Reference numeral 13 denotes a cable conductor, 14 denotes a cable shielding layer, and 15 denotes a straight connection portion. In a normal state, the cable shielding layers 14 are grounded at the cable end portions A and F, respectively.

FIG. 6 shows a situation in which insulation deterioration diagnosis is performed in a live state on this line. That is, the cable shielding layer 14 of the cable to be measured is provided with the insulation deterioration diagnostic device 1.
For example, when the measurement is performed by connecting the insulation deterioration diagnostic device 16 to the terminal A, it is necessary to float the ground at the other terminal F.

The drawback of the straight-line connecting portion configured as shown in FIG. 3 is that the insulation has deteriorated when it is determined that the power cable needs to be replaced by performing the insulation deterioration diagnosis in the state of FIG. The inability to identify the power cable or connection. In other words, the power cable between the CDs is actually insulated and deteriorated, and the deteriorated portion cannot be specified even if the other portions are sound, so that all the lines between the AFs are replaced. .

What compensates for this drawback is the line shown in the schematic diagram of FIG. That is, the linear connection parts B, C, D,
In E, the cable shielding layer 14 has a structure that can be easily separated electrically, for example, the straight connection portion C
When performing the deterioration diagnosis between D, the insulation deterioration diagnosis device 16 can be measured by separating the cable shielding layer 14 of the linear connection portions C and D. That is, it is possible to diagnose the insulation deterioration of the cable from each straight connection portion as a starting point, and to specify the line to be replaced.

FIG. 9 shows a conventional technique of 22 kV which makes it possible to separate the cable shielding layer as shown in the schematic view of FIG.
FIG. 3 is a cross-sectional view showing a configuration of a straight connection portion for a CV cable. Cable conductor 2 of left and right CV cables 31 in this figure
8 are connected to each other by a compression sleeve 17 under pressure. A sleeve cover 18 formed of semiconductive rubber is attached around the sleeve 17, and an inner semiconductive sleeve is formed around the sleeve cover 18 as in FIG. An insulating cylinder 19 in which a layer, an insulating layer, and an external semiconductive layer are integrally formed is located. The sleeve cover 18 includes the cable conductor 28 and the compression sleeve 1.
The component for electrically setting the inner semiconductive layer of the insulating tube 19 to the same potential as the component 7 is the same as that shown in FIG. Around the cable insulator 29, an insulating rubber and a semi-conductive rubber which fill a gap with the insulating tube 19 and play a role of reinforcing insulation, and further have a role of electric field relaxation at a rising portion of the cable shielding layer 30 are formed. Integrally formed spacers 20 and 2
1 is located.

The details of these spacers 20, 21 are shown in FIG.
0 and FIG. That is, the spacers 20 and 21
The structure of the left and right cables is different.
In FIG. 9, the semiconductive rubber 21b of FIG. 9 comes into contact with the outer semiconductive layer of the insulating cylinder 19 and thus has the same electric potential.
Since a is formed so as to form the shield insulating portion 32, it is electrically insulated from the outer semiconductive layer of the insulating cylinder 19 as shown in FIG.

The location where the semiconductive tape 22 is wound is also different in the location where it is wound in the left and right cables. In the left cable, the portion between the cable shielding layer 30 and the outer semiconductive layer of the insulating tube 19 and the semiconductive rubber 21b of the spacer 21 is different. A structure in which the right cable is wound from the cable shielding layer 30 to the semiconductive rubber 20b of the spacer 20 while the coil is wound up on the insulating tube 19 in order to further secure the electrical connection and prevent the displacement of the insulating tube. And

The winding position of the insulating tape 23 is also different on the left and right. The left cable is wound mainly to eliminate the step of the connecting portion, whereas the right cable is wound on the outer semiconductive portion of the insulating tube 19. Insulating tape 23 for further ensuring electrical insulation between the layer and the semiconductive rubber 20b of the spacer 20 and for preventing displacement of the insulating cylinder 19
Is wound up onto the insulating tube 19. That is,
The left and right power cables have different tape application methods.

Further, a shrinkable tube 24 is provided on the connection portion for improving waterproofness, and a waterproof tape 25 is wound thereon. Ground wires 33 to which crimp terminals 27 are attached are connected to the left and right cable shielding layers 30, respectively. The left and right ground wires are connected by screws 26, and the insulating tape 23 is connected to the ground wire for waterproofing. It is wound around the club.

In the line provided with the straight-line connecting portion constructed as described above, when performing insulation deterioration diagnosis on a live line as shown in the simulation diagram of FIG. 8, the insulating tape 23 is removed and the screw 26 is removed. The cable shielding layer can be cut off and trimmed.

[0016]

By the way, the problems of the prior art described above are as follows: (1) Since the edge of the cable shielding layer is cut by the spacer, two types of spacers are required for each cable size. Poor. (2)
If the two types of spacers are interchanged and constructed, the cable shielding layer will not be cut off and will be a normal linear connection. (3) Insulation tape,
The construction work of the semiconductive tape is different, and it is easy to make work mistakes. And the like.

The present invention has been made in view of the above points, and solves the above-mentioned disadvantages of the prior art, hardly causes construction errors, and is economically advantageous. It is intended to provide a straight connection.

[0018] In the plug-in type straight connection portion which enables the trimming of the cable shielding layer, the trimming of the cable shielding layer is performed by an insulating cylinder provided on the conductor connecting portion and on the cable insulator via a spacer. The insulating tube is formed by integrally molding an inner semiconductive layer, an insulating layer, an outer semiconductive layer, and an outer insulating layer. One end of the outer semiconductive layer of the insulating tube is covered with the outer insulating layer to be concealed. Of the outer semiconductive layer at the other end of the insulating cylinder around the outer insulating layer.
A cable shield characterized by forming a tapered portion corresponding to the taper portion and applying a semiconductive tape from this tapered portion to the cable shielding layer to enable the edge of the cable shielding layer to be cut at a straight connection portion. Insulated plug-in straight connection.

[0019]

According to the present invention, the insulation of the cable shielding layer is performed by using an insulating cylinder instead of a spacer, and the insulating cylinder is provided with an insulating layer so as to cover the outer semiconductive layer at one end of the insulating cylinder. The left and right spacers can be the same. In addition, by making the semiconductive tape winding work the same on the left and right, it is possible to completely prevent the occurrence of a work error.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a configuration of a cable shield insulated plug-in straight connection portion for a 6600 VCV cable showing one embodiment. That is, the positions, structures and roles of the compression sleeve 1, the sleeve cover 2 and the spacer 4 are the same as those of the conventional example shown in FIG. On the sleeve cover 2 and the spacer 4, the insulating cylinder 34 of the present invention is arranged.

The insulating cylinder 34 is an integrally molded product of an inner semiconductive layer 34a, an insulating layer 34b, an outer semiconductive layer 34c and an outer insulating layer 34e, as shown in FIG. External semiconductive layer 34 on one side of insulating cylinder 34
It is formed so as to hide c.

The semiconductive tape 5 is wound from the cable shielding layer 10 at both ends of the end of the insulating tube 34 to a position above the tapered portion 34d or 34f of the insulating tube 34 so that the electric field is relaxed at the end of the spacer 4. I have to. Further, the shielding portion 39 is formed by winding the semiconductive tape 5 at both ends in the same manner as in the conventional example described above.

The crimp terminals 3 are provided on the left and right cable shielding layers 10.
6 are connected to each other by screws 35, and are connected to each other by screws 35, and a configuration in which an insulating tape 37 is applied and a configuration in which a waterproof tape 7 is applied from the entire connection portion to the cable sheath 11 are shown in FIG. Are the same as those of the conventional example shown in FIG.

Therefore, the insulating cylinder 34 thus constructed
, The spacers may be the same on the left and right, and the semiconductive tape to be wound on them may be formed by being wound on the left and right in the same manner.

[0025]

As described above, in the cable-insulated insulated plug-in straight connection portion of the present invention, since the edge of the cable-shielding layer is cut by the insulating cylinder, only one type of spacer is required regardless of the cable size. It is economically advantageous.
In addition, since the tape winding work on the left and right of the connecting portion can be made the same, there is no possibility that a work error occurs. That is, by performing the same operation as a normal plug-in type straight connection portion which does not cut off the cable shielding layer, a shielded insulation type straight connection portion can be formed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration of a cable shield insulating type plug-in linear connection portion according to an embodiment of the present invention;

FIG. 2 is an enlarged cross-sectional view of the insulating cylinder of FIG. 1;

FIG. 3 is a cross-sectional view showing a configuration of a conventional plug-in straight connection portion;

4 is an enlarged cross-sectional view of the insulating cylinder of FIG. 3,

FIG. 5 is a schematic diagram showing a grounding state in a state where a conventional plug-in straight connection portion is applied to a line;

6 is a simulation diagram when diagnosing insulation deterioration of the line in FIG. 5,

FIG. 7 is a schematic diagram showing a grounding state in a state where a shielded insulation type plug-in straight connection portion is applied to a line;

8 is a simulation diagram when diagnosing insulation deterioration of the line in FIG. 7;

FIG. 9 is a cross-sectional view showing the configuration of a conventional shielded insulation type plug-in straight connection portion;

FIG. 10 is a sectional view showing the configuration of the left spacer of FIG. 9;

FIG. 11 is a sectional view showing a configuration of a right spacer of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compression sleeve 2 Sleeve cover 4 Spacer 5 Semiconductive tape 7 Waterproof tape 8 Cable conductor 9 Cable insulator 10 Cable shielding layer 34 Insulation cylinder 34a Internal semiconductive layer 34b Insulating layer 34c External semiconductive layer 35 Screw 36 Compression terminal 37 Insulation Tape 38 Ground wire

Claims (1)

(57) [Claims] In a plug-in type straight connection portion capable of trimming a cable shielding layer, the cable shielding layer is trimmed with an insulating cylinder provided on a conductor connecting portion and on a cable insulator via a spacer. The insulating cylinder is formed by integrally forming an inner semiconductive layer, an insulating layer, an outer semiconductive layer and an outer insulating layer. One end of the outer semiconductive layer of the insulating cylinder is covered with the outer insulating layer. in concealed structure Te, Te of the outer semiconducting layer end of the other one end of the insulating tube in the outer insulating layer periphery
A cable shield characterized by forming a tapered portion corresponding to the taper portion and applying a semiconductive tape from this tapered portion to the cable shielding layer to enable the edge of the cable shielding layer to be cut at a straight connection portion. Insulated plug-in connection.