JPH0923558A - Power cable prefabricated structure - Google Patents

Abstract

(57) [PROBLEMS] To provide a prefabricated structure of a power cable that surely connects a stopper and a conductor connecting body. A premolded insulator (03a) pressed by a mechanical compression device has a stopper (109a) embedded therein.
Press on 08. The conductor connection body (conductor connection pipe) 105 connected to the cable conductor 104a and the stopper are connected by a connection line 1. Therefore, electrical contact between the stopper and the conductor connection body is ensured, so that the electric field on the cable conductor side can be reliably mitigated, and corona discharge and breakage of the cable insulator can be reliably prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power cable prefabricated structure, and more particularly to a power cable prefabricated structure such as an ultra-high voltage CV cable.

[0002]

2. Description of the Related Art Conventionally, a prefabricated intermediate junction box has been known as an intermediate connection means for an ultrahigh voltage CV cable, and a premolded insulation type termination box has been known as an end connection means.

FIG. 4 is a sectional view of an example of a conventional prefabricated intermediate junction box. As shown in FIG. 4, the cable insulators 102a, 1 of the two CV cables 101a, 101b.
02b, the premolded insulators 103a and 103b, and the cable conductors 104a and 104b are arranged to face each other. The tip ends of the cable conductors 104a and 104b are conductor connecting tubes 1
05, and the ring 106 is fitted in the central portion of the conductor connecting pipe 105. A plurality of pins 107 are provided so as to project outward from the outer peripheral portion of the ring 106.

On the other hand, on the inner peripheral surface side of the cylindrical epoxy unit 111, a cylindrical embedded electrode 108 made of aluminum is arranged at a position corresponding to the ring 106, and the left end of the embedded electrode 108. Surface and premolded insulator 1
A stopper 109a made of copper is fitted between the end face of 03a and the end face of 03a, and the right end face of the embedded electrode 108 and the pre-mold insulator 1 are inserted.
A stopper 109b is fitted between the end surface of 03b.

FIG. 5 is a sectional view of an example of a conventional premolded insulation type termination box. A conductor pull-out rod 112 is fitted in the axial direction of the cable conductor 104b. An epoxy porcelain tube 114 is arranged so as to cover the premolded insulator 103b. A buried electrode 113 is arranged inside the tip of the epoxy porcelain tube 114. A stopper 115 is arranged between the right end surface of the embedded electrode 113 and the end surface of the premolded insulator 103b. Reference numeral 116 is an O-ring.

In the prefabricated intermediate junction box or the premolded insulation type termination box having the above-described structure, the stopper and the conductor connection pipe (or the conductor lead-out rod) are connected to the premolded insulator by the spring compression device (see FIG. Electrical contact is ensured by pushing the stopper toward the embedded electrode connected to the conductor connecting pipe (or the conductor lead-out rod) by pushing the stopper toward the stopper by a not-shown). That is, the same potential is reliably ensured between the cable conductor, the conductor connection pipe (or the conductor lead-out rod), the embedded electrode, and the stopper.

[0007]

However, the above-mentioned conventional means have the following drawbacks. That is, there is a possibility that the stopper does not come into contact with the embedded electrode due to a mistake in assembling the pre-molded insulator, and the stopper and the conductor connecting pipe (or conductor lead-out rod; hereinafter also referred to as conductor connecting body) It is impossible to confirm whether or not the contact is made with certainty.

Therefore, an object of the present invention is to provide a prefabricated structure of a power cable which surely connects a stopper and a conductor connecting body.

[0009]

In order to solve the above-mentioned problems, the invention according to claim 1 is directed to a premold insulator which is pressed by a mechanical compression device, and a pressing force is applied through the premold insulator. An epoxy unit, an embedded electrode embedded in the epoxy unit, a metal stopper interposed between the premolded insulator and the embedded electrode, and a conductor connection body connected to the cable conductor. In a prefabricated structure of a power cable including the above, the stopper and the conductor connection body are connected by a connection line for conduction.

According to the first aspect of the present invention, the premolded insulator pressed by the mechanical compression device presses the stopper against the embedded electrode. The conductor connection body connected to the cable conductor and the stopper are connected by a connection line. Therefore, the electrical contact between the stopper and the conductor connection body is ensured, so that the electric field near the tip of the premolded insulator can be surely relaxed, and the occurrence of corona discharge and the accompanying dielectric breakdown can be prevented.

According to a second aspect of the present invention, a pre-mold insulator pressed by a mechanical compression device, an epoxy unit to which a pressing force is applied via the pre-mold insulator, and an epoxy unit embedded in the epoxy unit. An embedded electrode, a metal stopper interposed between the premolded insulator and the embedded electrode, a conductor connecting body connected to the cable conductor, and a ring fitted in the conductor connecting body. In the prefabricated structure of the power cable including the above, the stopper and the ring are connected by a connecting wire for conduction.

According to the second aspect of the present invention, the electric contact between the stopper and the ring is ensured, so that the electric field on the cable conductor side can be reliably mitigated, and the corona discharge and the breakage of the cable insulator can be reliably prevented. can do.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the illustrated embodiments of the invention. Note that the same reference numerals are given to the already described portions, and redundant description is omitted.

(1) Example of First Embodiment FIG. 1 shows a cross-sectional view of one side after completion of assembly of a prefabricated junction box of an example of the first embodiment. As shown in FIG. 1, one end of a connecting wire 1 made of a braided wire, a copper wire or the like is fixedly connected to the inner surface of the stopper 109a, and the other end is a ring 106.
Is fixedly connected to the side surface of the with screws 2.

When assembling, first, one end of the connecting wire 1 is connected and fixed to the inner peripheral surface of the stopper 109a by soldering. As a place for this soldering, a place where no electrical stress is applied is suitable. Then, at the time of assembly, the side surface of the ring 106 is connected and fixed by the screw 2. The screws 2 may be connected and fixed by soldering. In this way, electrical contact between the stopper 109a and the conductor connecting pipe 105 can be ensured.

(2) Example of Second Embodiment FIG. 2 is a cross-sectional view of one side after completion of assembly of the prefabricated junction box of the example of the second embodiment. As shown in FIG. 2, one end of the connecting wire 1a is fixedly connected to the inner surface side of the stopper 109a, and the other end is fixedly wound around the outer peripheral surface of the conductor connecting pipe 105 by the plated wire 3.

When assembling, first, one end of the connecting wire 1a is connected and fixed to the inner peripheral surface of the stopper 109a by soldering, and then the conductor connecting pipe 10 is assembled at the time of assembling.
The plated wire 3 is wound around the outer peripheral surface of 5 to be connected and fixed. In this way, electrical contact between the stopper 109a and the conductor connecting pipe 105 can be ensured.

Further, according to the examples of the first and second embodiments, the heat generated in the conductor connecting pipe 105 can be transferred to the stopper 109a through the connecting wires 1 and 1a.
The temperature rise of the conductor connecting pipe 105 can be suppressed.

(3) Example of Third Embodiment FIG. 3 is a sectional view of the premolded insulation type termination box of the third embodiment after assembly is completed.

As shown in FIG. 3, one end of the connecting wire 5 is fixedly connected to the inner surface side of the stopper 115, and the other end is fixedly connected to the outer peripheral surface of the conductor drawing rod 112 by a screw 4. When assembling, first, one end of the connecting wire 5 is connected and fixed to the inner peripheral surface of the stopper 115 by soldering.
Next, at the time of assembly, the outer peripheral surface of the conductor pull-out rod 112 is connected and fixed by the screw 4. By doing so, the stopper 1
It is possible to secure electrical contact between 15 and the conductor pull-out rod 112.

[0021]

As described above, according to the invention described in each claim, since the stopper and the conductor connecting body or the ring are surely connected by the connecting wire, the electric field relaxation on the cable conductor side is surely performed. Therefore, it is possible to reliably prevent corona discharge and dielectric breakdown due to corona discharge.

[Brief description of drawings]

FIG. 1 is a sectional view of an example of a first exemplary embodiment of the present invention.

FIG. 2 is a sectional view of an example of a second embodiment of the present invention.

FIG. 3 is a sectional view of an example of a third embodiment of the present invention.

FIG. 4 is a sectional view of a conventional example.

FIG. 5 is a sectional view of another conventional example.

[Explanation of symbols]

 1,1a, 5 Connection wire 2,4 Screw 3 Plated wire 101a Cable 103a Pre-molded insulator 104a Cable conductor 105 Conductor connection pipe (conductor connection body) 106 Ring 107 pin 108,113 Embedded electrode 109a, 115 Stopper 112 Conductor extraction Rod (conductor connection body)

Claims (2)

[Claims] 1. A premold insulator pressed by a mechanical compression device, an epoxy unit to which a pressing force is applied in a predetermined direction through the premold insulator, and an embedded electrode embedded in the epoxy unit. A prefabricated structure of a power cable comprising a metal stopper interposed between the premold insulator and the embedded electrode, and a conductor connecting body connected to the cable conductor, wherein the stopper and the conductor connecting body A prefabricated structure of a power cable, characterized in that and are connected by a connecting line for conduction. 2. A pre-molded insulator pressed by a mechanical compression device, an epoxy unit to which a pressing force is applied via the pre-molded insulator, an embedded electrode embedded in the epoxy unit, and the pre-molded insulator. A power cable prefabricated structure including a metal stopper interposed between the mold insulator and the embedded electrode, a conductor connecting body connected to the cable conductor, and a ring fitted in the conductor connecting body. The prefabricated structure of a power cable, wherein the stopper and the ring are connected by a connection line for conduction.