JP2002118914A - Grounded fitting for multi-core transmission line - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a grounded metal base to which a plurality of pieces of grounding metals are installed, when a multi-core transmission line having a large induced current is grounded. SOLUTION: The grounded metal base is composed of a rod-shaped grounded conductor 34, of a length with a plurality of pieces of grounding metals 24 capable of being installed on the grounded conductor, an oval corona prevention ring 32 on which the rod-shaped grounded conductor 34 is installed facing in the direction of the long axis thereof, and a plurality of brackets 36A and 36B for installing the corona prevention ring 32 on a multi-core transmission line 10, so that the corona prevention ring is positioned outside an area encircled by the plurality of the conductors of the multi-core transmission line 10. The longer bracket 36A has two joint portions 44A and 44B, and the shorter bracket 36B has one joint portion 48 so that the corona prevention ring 32 can be horizontally installed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a grounded metal fitting which is mainly attached to a multi-conductor transmission line (including a multi-conductor bus) of 500 kV or more at a substation or a switchyard.

[0002]

2. Description of the Related Art When inspecting or repairing equipment at a power station or a substation, etc., after the power line connected to the equipment is cut off,
Work after grounding the transmission line. In the case of a multiconductor transmission line, grounding is performed as shown in FIG. In the figure, 10
Is a multi-conductor transmission line (three conductors in the example shown) installed at a power substation, etc., 12 is a steel structure, 14 is a suspension insulator, 16 is a GIS (gas insulated switchgear), 18 is a multi-conductor transmission line 10 The spacer 20 for maintaining the conductor interval is a spacer type grounded metal fitting attached to the lowered portion of the multiconductor power transmission line 10. When grounding the multiconductor power transmission line 10, the grounding wheel 22 is disposed directly below the grounded metal fitting 20, an outrigger (not shown) is extended, and an insulating rod 26 having a grounding metal fitting 24 attached to the upper end thereof. Is extended upward, and the grounded bracket 20 is sandwiched by the grounding bracket 24. Since a ground wire 28 is connected to the grounding bracket 24 in advance, when the grounded bracket 20 is sandwiched by the grounding bracket 24, the multi-conductor transmission line 10
Can be grounded.

[0003]

The multi-conductor transmission line 10 to be grounded receives an induced current from an adjacent multi-conductor transmission line in a live state. This induced current is about 500A for a 500kV multi-conductor transmission line, and the grounding bracket 24 and the grounding wire
28 has a problem of overheating. In order to prevent overheating, it is conceivable to attach two grounding brackets 24 to the grounded bracket 20, but since the dimensions of the grounded bracket are determined by the conductor spacing of the multi-conductor transmission line, the grounding bracket must be mounted on the ground. Two cannot be attached.

[0004] In addition, 1) it is difficult to attach the grounding bracket to the spacer-type grounded bracket because the width of the grounding bracket mounting portion is narrow, and 2) the grounding work is careful because the GIS bushing 16a is nearby. There is also a problem that it takes time, and 3) when trying to overhang the outrigger of the ground contact vehicle, it hits the GIS foundation and an appropriate working environment cannot be created.

An object of the present invention is to provide a grounded metal fitting for a multi-conductor power transmission line which has solved the above problems.

[0006]

According to the present invention, there is provided a grounded metal fitting for a multiconductor power transmission line, comprising: a rod-shaped grounded conductor having a length to which a plurality of grounding metal fittings can be attached; Oval or circular corona-prevention ring attached to the multi-conductor transmission line, and a plurality of attachments for attaching the corona prevention ring to the multi-conductor transmission line so as to be located outside the region surrounded by the plurality of conductors of the multi-conductor transmission line And metal fittings.

By using such a grounded metal fitting, a plurality of grounding metal fittings can be attached to the bar-shaped grounded conductor, so that the problem of overheating can be solved. The bar-shaped grounded conductor is located outside the multiconductor power transmission line, but is surrounded by the corona prevention ring, so that there is little possibility that corona will be generated during energization.

In the metal fitting to be grounded of the present invention, of the plurality of metal fittings, the metal fitting above the inclined multi-conductor power transmission line is longer than the short metal fitting below the same multi-conductor power transmission line. The longer mounting bracket includes a fixing bracket fixed to the corona prevention ring, a clamp for gripping the conductor of the multi-conductor power transmission line, and a connecting rod for connecting between the fixing bracket and the clamp. The joint between the fixing bracket and the connecting rod and the joint between the clamp and the connecting rod are bendable joints. The shorter mounting bracket is a fixing bracket fixed to the corona prevention ring and a multi-conductor transmission line. And a connecting portion between the fixture and the clamp is a bendable joint.

[0009] With this configuration, when the grounded metal fitting is attached to the inclined multi-conductor power transmission line, the corona-prevention ring is placed substantially horizontally outside the multi-conductor power transmission line regardless of the degree of inclination of the multi-conductor power transmission line. Can be attached to As a result, since the bar-shaped grounded conductor is disposed apart from the multiconductor power transmission line, the grounding operation can be easily performed in a short time.

[0010] The grounded metal fitting of the present invention may be configured such that, when a multi-conductor power transmission line is energized, a loop composed of the mounting metal, a corona-prevention ring, and a multi-conductor power transmission line between the mounting metal is provided in a part of the mounting metal. It is preferable to provide a structure provided with an insulating portion for preventing a circulating current from flowing. With this configuration, it is possible to prevent the grounded metal fitting from being overheated by the circulating current.

[0011]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 shows an embodiment of a grounded metal fitting of the present invention. The grounded metal fitting 30 includes an oval corona prevention ring 32, a rod-shaped grounded conductor 34 attached to the corona prevention ring 32 in the longitudinal direction as shown in FIG. 2, and a rod-shaped grounded conductor 34. A plurality of mounting brackets 36A and 36B for mounting the corona prevention ring 32 provided with a circle substantially horizontally on the outside of the multiconductor power transmission line 10 inclined as shown in FIG.

As shown in FIG. 1, the rod-like grounded conductor 34 has a length enough to mount two grounding fittings 24 thereon.
The bar-shaped grounded conductor 34 and the corona prevention ring 32 can be formed of an aluminum or aluminum alloy pipe. Of the mounting brackets 36A and 36B, the mounting bracket 36A that grips the upper side of the inclined multi-conductor power transmission line 10 is longer than the mounting bracket 36B that grips the lower side of the same multi-conductor power transmission line 10. Two sets of the longer mounting brackets 36A are attached to one straight portion of the oval corona prevention ring 32, and two sets of the shorter mounting brackets 36B are mounted to the other straight portion of the corona prevention ring 32. .

The longer mounting bracket 36A includes a fixing bracket 38 fixed to one straight portion of the corona prevention ring 32 so as to stand up therefrom, a clamp 40 for gripping the conductor of the multiconductor power transmission line 10, and a And a connecting portion of the fixing bracket 38 and the connecting rod 42 and a clamp.
Joint part 44 where the connection part between 40 and connecting rod 42 can be bent
A, 44B. In addition, the shorter mounting bracket 36B grips a fixing metal 45 (shorter than the fixing metal 38) fixed to the other linear portion of the corona prevention ring 32 so as to stand up therefrom, and a conductor of the multiconductor power transmission line 10. It comprises a clamp 46, and a joint between the fixing bracket 45 and the clamp 46 is a bendable joint 48.

The clamps 40 and 46 have the same structure. As shown in FIG. 3, one of the members of the conductor gripping portion 49 is extended in a crank shape to form a joint connection part 50 having a joint at the end. Things.

The connecting rod 42 of the longer mounting bracket 36A has a structure as shown in FIG. That is, two connection members formed by welding a connection part 54 having a joint for a joint to one end of a metal pipe 52 such as aluminum or an aluminum alloy, and a connection part 56 having a plurality of bolt holes at the other end, A connecting plate 56 of both members is overlapped via an insulating plate 58, and is connected by tightening with a plurality of bolts and nuts 60. Bolt and nut 60
Is insulated from the connecting plate 56 by an insulating sleeve 62 and an insulating washer 64. The reason why the connecting rod 42 has such a structure is to provide an electrical insulating portion in the middle. Each of the joints 44A, 44B, and 48 is configured by rotatably connecting a perforated connection part of an adjacent member with a shaft pin.

The grounded metal fitting 30 for a multi-conductor power transmission line constructed as described above has two joints attached to the longer mounting metal 36A.
44A and 44B, and one joint 48 on the shorter mounting bracket 36B. By adjusting the mounting intervals of the clamps 40 and 46, the corona The prevention ring 32 can be mounted horizontally. If the corona prevention ring 32 is mounted horizontally, the grounding bracket 24 can be most easily mounted on the bar-shaped grounded conductor.

FIG. 1 shows a case where the degree of inclination of the multi-conductor power transmission line 10 is relatively steep. If the inclination of the multi-conductor power transmission line 10 is gentler than this, for example, the multi-conductor power transmission line 10 can be attached as shown in FIG. In other words, regardless of the degree of inclination of the multi-conductor power transmission line 10, the grounded metal fitting 30 of this embodiment has a corona prevention ring 32.
Can be mounted horizontally.

Further, since the insulating portion 58 is provided in the middle of the connecting rod 42, when the multi-conductor power transmission line 10 is in an energized state, the multi-conductor power transmission line 10 circulates in a loop formed by the grounded metal fitting 30 and the multi-conductor power transmission line 10. Current does not flow, and overheating due to the circulating current of the metal fitting 30 can be prevented.

In the above embodiment, the case where the grounded metal fitting 30 is attached to the inclined multi-conductor power transmission line 10 (the lowered portion of the multi-conductor power transmission line) has been described. However, the grounded metal fitting of the present invention is a horizontal or vertical metal. It can be attached to a multi-conductor power transmission line. When mounting on a horizontal multi-conductor power line, all the mounting brackets need to be the same length.When mounting on a vertical multi-conductor power line, bend the connecting rod so that the clamps 40 and 46 are in a vertical arrangement. Good.

[0020]

As described above, according to the present invention, a rod-like grounded conductor having a length to which a plurality of grounding fittings can be attached is formed in a multi-conductor transmission line in a state where the corona is prevented from being generated in the corona. Since it can be arranged on the outside, a plurality of grounding brackets can be easily attached to the rod-shaped grounded conductor at the time of power failure. Therefore, overheating of the grounding bracket and the grounding line due to the induced current can be prevented, and a highly safe grounding state can be obtained.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a grounded metal fitting for a multiconductor power transmission line according to the present invention in use, (A) is a side view, and (B) is a front view.

2 (A) is a plan view, FIG. 2 (B) is a front view, and FIG. 2 (C) is a side view of a corona prevention ring with a rod-shaped grounded conductor constituting the grounded metal fitting of FIG.

FIG. 3 shows a clamp constituting the grounded metal fitting of FIG. 1;
(A) is a side view, (B) is a front view.

FIG. 4 is a sectional view of a connecting rod constituting the grounded metal fitting of FIG. 1;

5A and 5B show a state where the grounded metal fitting of FIG. 1 is attached to a multi-conductor transmission line having different inclinations, wherein FIG. 5A is a side view and FIG. 5B is a front view.

FIG. 6 shows a conventional grounding operation of a multi-conductor power transmission line, (A)
1 is an overall explanatory view, and FIG. 1B is a view taken along line BB in FIG.

[Explanation of symbols]

 10: Multi-conductor power line 30: Grounded metal fitting for multi-conductor power line 32: Corona prevention ring 34: Bar-shaped grounded conductor 36A: Longer mounting bracket 36B: Shorter mounting bracket 38: Fixing bracket 40: Clamp 42: Connecting rod 44A, 44B: Joint 45: Fixing bracket 46: Clamp 48: Joint 58: Insulating plate 60: Bolt and nut 63: Insulating sleeve 64: Insulating bush

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takao Noguchi 2-6-1 Marunouchi, Chiyoda-ku, Tokyo Furukawa Electric Co., Ltd. (72) Inventor Hiroshi Ikeda 1-3-1 Uchisaiwaicho, Chiyoda-ku, Tokyo Tokyo Electric Power Company F-term (reference) 3J022 DA11 EA42 EB14 EC14 EC22 ED23 FA01 FB06 FB12 FB17 FB24 GA03 GA12 GB42 GB44 GB53 GB77 5G369 AA16 BA01 EA03

Claims (3)

[Claims] 1. A rod-shaped grounded conductor (34) having a length to which a plurality of grounding fittings (24) can be attached;
4) An oblong or circular corona prevention ring (32) attached in the longitudinal or diametric direction, and the corona prevention ring (32) is surrounded by a plurality of conductors of the multiconductor power transmission line (10). Multi-conductor transmission line (1
A grounded metal fitting for a multi-conductor power transmission line, comprising: a plurality of metal fittings (36A, 36B) to be attached to 0). 2. A plurality of mounting brackets (36A, 36B).
The mounting bracket (36A) that grips the upper side of the inclined multi-conductor transmission line (10) is longer and longer than the short mounting bracket (36B) that grips the lower side of the same multi-conductor transmission line (10). One of the mounting brackets (36A) is a corona prevention ring (3
2) Fixing bracket (38) and multi-conductor transmission line (1
0) and a connecting rod (4) for connecting between the fixing bracket (38) and the clamp (40).
2), the joint between the fixing bracket (38) and the connecting rod (42) and the joint between the clamp (38) and the connecting rod (42) are bendable joints (44A, 44B), The shorter mounting bracket (36B) is attached to the anti-corona ring (3
2) Fixing bracket (45) and multi-conductor transmission line (1
The clamp (46) for gripping the conductor of (0), wherein a connecting portion between the fixing bracket (45) and the clamp (46) is a bendable joint (48). 2. The grounded metal fitting for a multiconductor power transmission line according to 1. 3. The mounting brackets (46A, 46B) are connected to a part of the mounting brackets (46A, 46B) when the multiconductor power transmission line (10) is energized.
3. An insulating part (58) for preventing a circulating current from flowing in a loop composed of a coil, a corona prevention ring (32) and a multi-conductor power transmission line (10). Grounded metal fittings for multi-conductor transmission lines.