JP4762970B2 - Power cable aerial termination connection and manufacturing method thereof - Google Patents

Description

  The present invention relates to a power cable aerial termination connection part and a method of manufacturing a power cable aerial termination connection part, and more particularly, to provide a barrier layer for suppressing the occurrence of a discharge path from the end of the power cable aerial termination connection part. The present invention relates to a power cable aerial terminal connection part and a method for manufacturing a power cable aerial terminal connection part.

  The power cable air termination unit is used, for example, for connecting a high-voltage power cable, and is used, for example, for emergency recovery or facility inspection. In general, the end portion of the power cable in-air terminal connection portion to which the power cable is connected has a straight shape (bluff shape) or a tapered shape (see, for example, Patent Document 1).

In addition, as a related technique, there is a conventional power cable termination connecting portion provided with an electric field relaxation layer in order to improve electrical performance (see, for example, Patent Document 2). Further, although the field is different from that of the power cable in-air termination connection portion, there are some wire spacers arranged between the electric wires that have annular pleats in order to prevent the electrical insulation performance from deteriorating. (For example, refer to Patent Document 3).
JP-A-10-117425 JP 2000-175344 A Japanese Patent Laid-Open No. 9-233661

However, since the shape of the end portion of the power cable in-air termination connection portion disclosed in Patent Document 1 is a precipice shape or a taper shape as described above, lightning impulse (abbreviated as “Imp.” For short) is applied. Occasionally, a surface flash (abbreviated as an external flash) phenomenon occurs in the outer rubber at a low voltage. At the time of this power application, the generation and progress of the discharge path has been confirmed by experiments of the present inventors at the end of the rubber cylindrical body (for example, the precipice-shaped portion), and the discharge path is the end of the rubber cylindrical body. It has been found that this occurs when the part is a precipice-shaped part or a tapered part.
The location where this discharge path occurs is not the maximum stress site on the surface of the rubber cylindrical body, and the cause cannot be predicted in advance by static analysis such as electric field analysis.

  Therefore, in order to solve the above problems, the present invention provides an Imp. When power is applied, the power cable air terminal connection part and the power cable air terminal connection part can suppress the generation of a discharge path from the end of the terminal tubular body of the air terminal connection part and improve the electrical characteristics. An object is to provide a manufacturing method.

In order to solve the above-mentioned problems, the power cable aerial terminal connection part of the present invention is configured such that the air cable ends in the end of the power cable aerial terminal connection part in which a cylindrical body having a pleat part and a body part is attached to the power cable. In a power cable in-air termination connection part having a barrier layer formed so as to protrude along the axial direction of the termination connection part, the barrier layer is separate from the cylindrical body arranged in the trunk part of the cylindrical body. It characterized that you have been formed in the tubular member.

In the power cable air terminal connection portion of the present invention, preferably, the tubular member is made of rubber, and is fixed by being contracted with respect to the outer periphery of the cylindrical body .

The power cable air terminal connection part of the present invention preferably has a gap formed along the axial direction of the air terminal connection part between the barrier layer and the end of the cylindrical body. and said that you are

The method for manufacturing a power cable air terminal connection part of the present invention is a method for manufacturing a power cable air terminal connection part in which a cylindrical body having an electrically insulating pleat is attached to a power cable,
By disposing a tubular member separate from the cylindrical body at the end of the cylindrical body, a barrier layer is formed so as to protrude along the axial direction of the air end connection portion. And

The manufacturing method of the power cable air termination connection part of the present invention is characterized in that the barrier layer is formed by shrinking a tube member made of rubber having electrical insulation .

  According to the present invention, Imp. When power is applied, the power cable air terminal connection part and the power cable air terminal connection part can suppress the generation of a discharge path from the end of the terminal tubular body of the air terminal connection part and improve the electrical characteristics. A manufacturing method can be provided.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
<First Embodiment>
FIG. 1 is a front view with a partial cross-section showing a first preferred embodiment of a power cable aerial termination connection portion of the present invention. FIG. 2 is a front view having a partial cross section showing an enlarged view of the vicinity of the barrier layer in the in-air terminal connection portion of the power cable of FIG.

In order to make the structure of the power cable in-air terminal 1 shown in FIG. 1 easier to understand, the upper left half from the central axis is shown in cross section, and the lower right half is shown in the shape of the outer periphery. The power cable aerial terminal connection portion 1 includes a cylindrical body 2 and a power cable 10. The tubular body 2 has a body portion 4 and a pleat portion 5. The cylindrical body 2 is formed along the axial direction L. The body 4 has a semiconductive layer 3 incorporated therein. The semiconductive layer 3 is designed to reduce the stress release cone electric field by arbitrarily designing its shape and position. For example, it is made of semiconductive silicone rubber. The other part of the cylindrical body 2 is made of electrically insulating rubber such as silicone rubber, and is preferably formed so as to be integrated with the semiconductive layer 3.

  As shown in FIG. 1, the size, quantity, and length of the pleats 5 are determined along the axial direction L by electrical insulation design, and the pleats 5 include a plurality of pleats 6, 7. Are formed at intervals from each other along the axial direction L. A through hole 8 is formed along the axial direction L in the body portion 4 and the pleated portion 5. The power cable 10 shown in FIG. 1 is press-fitted into the through hole 8, so that the power cable in-air terminal connection portion 1 is connected and fixed to the power cable 10.

  As shown in FIG. 1, the power cable 10 includes a conductor 11, an electrical insulating portion 12 formed on the outer periphery of the conductor 11, an external semiconductive layer 13 disposed on the outer periphery of the electrical insulating portion 12, and a conductive property. A conductor pull-out bar 14 having The conductor lead bar 14 is fixed to the end of the conductor 11, and the conductor lead bar 14 has a tapered surface 15 so that the power cable 10 can be easily pressed into the through hole 8.

Further, the tubular body 2, this is a power cable 10 to retract and the power cable 10, the conductors 11 and the electrical insulation portion 12 and the outer semiconductive layer 13 described above by stripping stage a predetermined length Each is exposed. In addition, a power cable 10 (not shown) is inserted into a predetermined position of the cylindrical body 2, the outer semiconductive layer 13 and the semiconductive layer 3 come into contact with each other at a predetermined position, and a predetermined amount in the body portion 4 and the pleated portion 5 is obtained. And the electrical insulating portion 12 are brought into contact with each other, and the conductor pull-out bar 14 protrudes from the cylindrical body 2.

  As shown in FIGS. 1 and 2 (a), the body part 4 has a large diameter part 20, a medium diameter part 21, and a small diameter part 22, and the large diameter part of the body part 4 as shown in FIG. The outer dimension S1 of 20 is larger than the largest outer dimension S2 of the pleated portion 5. A barrier layer 30 is disposed in the middle diameter portion 21 so as to protrude along the axial direction L.

  This barrier layer 30 can be referred to as a pleat formed so as to protrude along the axial direction L. The barrier layer 30 is a tubular member formed using a material having electrical insulation, and the barrier layer 30 is preferably formed of a rubber material having the same electrical insulation as that of the cylindrical body 2. The difference between the outer dimensions of the large-diameter portion 20 and the outer-diameter portion 21 is preferably the same as the thickness N of the barrier layer 30, so that even if the barrier layer 30 is disposed on the intermediate-diameter portion 21, the barrier The layer 30 does not protrude outward in the radial direction from the large-diameter portion 20, and the maximum outer dimension of the body portion 4 can be prevented from expanding.

  As shown in FIG. 2A, the barrier layer 30 has a gap 31 formed along the axial direction L between the end of the body portion 4. The depth M along the axial direction L of the gap 31 is 5 mm to 100 mm, and the width H of the gap 31 in the direction orthogonal to the axial direction L is 5 mm to 50 mm. If the depth M is smaller than 5 mm, a discharge path may be generated, which is not preferable. If the depth M is larger than 100 mm, the length T of the barrier layer 30 in the axial direction L becomes longer. Is unfavorable because it increases. Further, if the width H is smaller than 5 mm, a discharge path may be generated, which is not preferable. If the width H is larger than 50 mm, the outer dimension of the body portion 4 is increased, which is not preferable.

  When manufacturing the power cable aerial terminal connection portion 1 shown in FIG. 1 and FIG. 2 (a), after manufacturing the cylindrical body 2 by rubber casting, in the end of the body portion 4 of the cylindrical body 2 After positioning the barrier layer 30, which is a tubular member, with respect to the outer periphery of the diameter portion 21, the barrier layer 30 is contracted by applying heat. Thereby, the barrier layer 30 can be disposed so as to protrude along the axial direction L at the end of the cylindrical body 2.

  In the power cable aerial terminal connection portion 1 shown in FIGS. 1 and 2A, the barrier layer 30 is provided on the body portion 4, so that Imp. When a voltage of plus or minus 650 kV is applied (applied) as a voltage, a discharge path does not occur, and the external flash performance of the power cable air terminal connection 1 is improved or stabilized.

FIG. 5 shows a state in which a discharge path 101 is generated in a conventional power cable aerial termination connection unit 100 as a comparative example of the above-described power cable aerial termination connection unit 1 of the first embodiment. In this conventional example, Imp. When a voltage of plus or minus 550 to 650 kV was applied as a voltage, a discharge path was generated.

  As described above, the power cable air end connection portions 1 and 1B according to the embodiment of the present invention are formed at the end portion of the body portion 4 of the tubular body 2 so as to protrude along the axial direction L of the tubular body 2. Each of the barrier layers 30.30B is formed. Thereby, the barrier layers 30 and 30 </ b> B can make the electrical insulation path longer, and can prevent the discharge path from being generated from the end of the body portion 4.

  The barrier layer 30 is a tubular member having electrical insulation disposed at the end of the body portion 4. Thereby, if a tubular member is prepared and arranged, the barrier layer 30 can be easily formed.

  The predetermined part (for example, the large diameter part 20, the medium diameter part 21, and the small diameter part 22) and the tubular member constituting the tubular body 2 of the air end connection part are made of rubber having electrical insulation, and the tube The cylindrical member is fixed by contracting with respect to the outer periphery of the power cable 10 of the cylindrical body 2 at the end-of-air connection after the cylindrical body 2 is formed. Thereby, the barrier layer 30 can be easily formed only by contracting the tubular member.

    In the manufacturing method of the power cable air terminal connection part of the embodiment of the present invention, a tube-shaped member is formed at the end part of the body part with respect to the outer periphery of the end part of the terminal cylindrical body of the body after the body is formed. By contracting, the barrier layer is formed by projecting along the axial direction of the main body. Thereby, the barrier layers 30 and 30B can make the electrical insulation path longer, and Imp. It is possible to suppress the occurrence of a discharge path from the end of the body part during power application.

  Further, in the method of manufacturing the power cable aerial termination connection part of the embodiment of the present invention, when forming the aerial termination connection part, by removing a part of the end of the body part, the axial direction of the main body A barrier layer is formed by protruding along the surface. Thereby, the barrier layers 30 and 30B can make the electrical insulation path longer, and Imp. It is possible to suppress the occurrence of a discharge path from the end of the body part during power application. Furthermore, a barrier layer made of the same material as that of the body portion can be formed without preparing a special separate member, and it is not necessary to increase the outer dimensions of the air terminal connection portion. Since a part of the cable is removed, the weight of the end portion of the power cable in the air can be reduced, and the amount of electrically insulating material having elasticity such as rubber can be reduced.

By the way, this invention is not limited to the said embodiment, A various modified example is employable.
For example, although the thickness of the barrier layers 30 and 30B is set to be the same along the axial direction L, the thickness is not limited to this, and the thickness may be changed along the axial direction L. The electrically insulating material of the barrier layer 30 may be different from the electrically insulating material of the cylindrical body 2.

  Further, in FIG. 2A, the barrier layer 30 is disposed on the medium diameter portion 21. However, as illustrated in FIG. 2B, the barrier layer 30 may be disposed on the large-diameter portion 20 without forming the medium-diameter portion 21. In the example shown in FIG. 4, the body portion 4 includes a large diameter portion 20B, an inclined portion 21C, and a small diameter portion 22B. However, the inclined portion 21C may not be provided, and the barrier layer 30B is formed from the large diameter portion 20B. You may form so that it may protrude directly.

  In addition, power cables have various structures from electrical and / or mechanical design. Therefore, the power cable air terminal connection portion is designed in accordance with the structure of the power cable, such as the step-off structure, the body portion, the pleat portion, and the semiconductive layer, that is, the structure of the power cable.

It is a front view which has a partial cross section which shows preferable 1st Embodiment of the air termination | terminus connection part of the electric power cable of this invention. FIG. 2A is a front view having a partial cross section showing the vicinity of the barrier layer in the air terminal connection portion of the power cable of FIG. 1 and FIG. 2B is a diagram showing another embodiment. is there. It is a front view which has a partial cross section which shows preferable 2nd Embodiment of the air termination | terminus connection part of the electric power cable of this invention. It is a front view which has the partial cross section which expands and shows the barrier layer vicinity in the air termination | terminus connection part of the electric power cable of FIG. It is a front view which has a partial cross section which shows the discharge path which generate | occur | produces in the air termination | terminus connection part of the conventional power cable as a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air termination | terminus connection part 1B Air termination | terminus connection part 2 Cylindrical body 2B Cylindrical body 3 Semiconducting layer 4 Body part 5 Corrugation part 10 Power cable 30 Barrier layer 30B Barrier layer 31 Gap 31B Gap L Axial direction

Claims (6)

An electric power having a barrier layer formed so as to protrude along the axial direction of the air termination connection portion at the end of the power cable air termination connection portion in which a cylindrical body having a pleat portion and a body portion is attached to the power cable the cable aerial sealing end, the barrier layer, the power cable aerial termination connection, wherein Rukoto the cylindrical body trunk portion arranged cylindrical body formed of a tubular member separate Department. The tubular member is made of rubber, a power cable aerial sealing end according to claim 1, characterized that you have been fixed by shrinking the outer periphery of the tubular body. 2. The power cable according to claim 1, wherein a gap is formed between the barrier layer and an end portion of the cylindrical body along an axial direction of the air termination connection portion. Air termination connection. A large-diameter portion and a medium-diameter portion are formed in the body portion of the tubular body of the air termination connection portion, and a difference between these external dimensions is formed larger than the thickness of the barrier layer. The power cable air termination connection part according to claim 1. A method for manufacturing a power cable air terminal connection portion in which a cylindrical body having an electrically insulating pleat is mounted on a power cable, wherein the tubular body is a separate member from the cylindrical body at the end of the cylindrical body. The barrier layer is formed so that it protrudes along the axial direction of the said air termination | terminus connection part by arrange | positioning, The manufacturing method of the electric cable cable termination | terminus terminal part characterized by the above-mentioned. 6. The method of manufacturing a power cable air terminal connection part according to claim 5, wherein the barrier layer is formed by shrinking a tube member made of rubber having electrical insulation.

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