JP2000294088A - Switch gear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a switch gear excellent in breakdown voltage, assuring safety, and capable of being constructed small. SOLUTION: A vacuum vessel 14 is equipped internally with a bus bar side conductor 3 furnished with a stationary electrode 3a at the forefront, a load side conductor 4, an operating member 5 to support a movable electrode 6 and contact it to the stationary electrode 3a and separate therefrom, and a flexible conductor 8 to connect the movable electrode 6 with the load side conductor 4. The bus bar side conductor 3 and load side conductor 4 are covered with covers 18 and 19 made of stainless steel. This heightens the withstand voltage between the bus bar side conductor 3, load side conductor 4, and vacuum vessel 14.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a main circuit opening / closing section for connecting / disconnecting a bus-side conductor and a load-side conductor in a vacuum vessel maintained at a high vacuum, and connecting / disconnecting a load-side conductor and a grounding conductor. The present invention relates to a switchgear provided with a grounding opening / closing part.

[0002]

2. Description of the Related Art A switchgear (closed switchboard) used to distribute electric power received from a bus to various load devices or other electric rooms includes a bus-side conductor for connection with the bus.
A connection conductor such as a load-side conductor for connection with a power transmission cable to a load, etc .; a main circuit switch for connecting / disconnecting the bus-side conductor and the load-side conductor; a ground switch for grounding the load-side conductor; and monitoring. Control devices and the like necessary for control are arranged in an outer box made of grounded metal. As one type of this type of switchgear, Japanese Patent Application Laid-Open No. Hei 7-28488 discloses that a main circuit switch and a ground switch are integrated with a part of a connection conductor and disposed in an outer box, and are connected to a bus and a power transmission cable. A switchgear having a configuration in which only connection is required is disclosed.

FIG. 7 is a side sectional view showing a configuration of a main part of the switchgear. This switchgear has insulating S
A bushing 7 for connecting a power transmission cable that penetrates a part of a peripheral wall of a metal container 71 in which F6 gas is sealed.
2a and a bushing 76a for busbar connection penetrating a part of the peripheral wall. The first, second and third switches 73, 74, 75 and the vacuum valve 79 are provided inside the container 71.
Is arranged.

[0004] The bus-bar-side conductor 76 is provided with an on-off switch (not shown) formed inside a vacuum valve 79 and a first switch 7.
3 is connected to the intermediate conductor 70 fixedly supported by the insulating support glass 70a fixed to a part of the peripheral wall of the container 71. Each branch path branched in two directions by the intermediate conductor 70 is connected to a load conductor 72 supported by a bushing 72a via second and third switches 74 and 75.
Via this load conductor 72, it is connected to an external power transmission cable (not shown).

In this switchgear, when an arc short circuit occurs in the container 71, the SF6 gas sealed in the container 71 may become high temperature and pressure in a short time due to the arc energy and explode. For this reason, it is necessary to provide an opening valve for releasing pressure in the container 71, and it is required that the container 71 be strong enough to withstand a high pressure state until the release of pressure is completed. Therefore, there has been a problem that the structure of the container 71 is complicated and the cost of the product is increased.

Further, the use of SF6 gas is avoided due to environmental problems. For this reason, taking advantage of the high arc-extinguishing property and insulating property in a vacuum state, the main circuit switch and the ground switch are housed in a vacuum vessel. A switchgear configured as shown in FIG. 8 was developed. This switchgear includes a bus-side conductor 83 having one end connected to a bus and the other end forming a fixed electrode 83a, and a load side connected to an external transmission line in a vacuum vessel 94 held in a high vacuum. A conductor 84 and the fixed electrode 8
An operation rod 85 that supports the movable electrode 86 via the connecting member 95 so as to face the 3a, and a flexible conductor 88 that connects the fixed member 87 joined in the middle of the movable electrode 86 to the load-side conductor 84. It is provided. Bus-side conductor 83
Is penetrated through a bushing 90 at one end wall of the vacuum vessel 94, and the operation rod 85 is supported by the other end wall of the vacuum vessel 94 via a bellows 92 so as to be movable in the axial direction, and a load-side conductor 84 is provided. Is penetrated through the peripheral wall of the vacuum vessel 94 via the bushing 91. A fixed contact 81 is fixed to the end of the fixed electrode 83 a of the bus-side conductor 83, and a movable contact 82 is fixed to the end of the movable electrode 86. A grounding conductor 89 is supported on the other end wall of the vacuum vessel 94 via a bellows 93 in parallel with the operation rod 85, and a movable contact 89a is provided at a tip end thereof and faces the movable contact 89a. A fixed contact 84a is provided on the peripheral surface of the load-side conductor 84.

The outer end of the operating rod 85 is connected to an operating mechanism (not shown), and the operating rod 85 is moved in the axial direction according to the operation of the operating mechanism. The grounding conductor 89 is also moved in the axial direction by an operation mechanism (not shown). The movement of the operating rod 85 is transmitted to the movable electrode 86 via the connecting member 95, the movable contact 82 at the tip of the movable electrode 86 comes into contact with and separates from the fixed contact 81, and is between the busbar conductor 83 and the load conductor 84, that is, The current is switched between the bus and the power transmission cable to the load.
When the movable contact 82 is separated from the fixed contact 81 and the main circuit current from the bus-side conductor 83 to the load-side conductor 84 is cut off, the grounding conductor 89 is moved upward in the figure to ensure safety. Then, the movable contact 89a is brought into contact with the fixed contact 84a of the load-side conductor 84.

Since the switchgear of FIG. 8 is used in a vacuum having excellent insulation properties, the required insulation distance between the members can be made smaller than that of the switchgear of FIG. I have. Further, even when an arc short-circuit occurs inside the vacuum vessel 94, there is no gas inside the vacuum vessel 94, so there is no danger of the above-mentioned arc short-circuit explosion.

[0009]

The switchgear shown in FIG. 8 is constructed as described above. However, the vacuum vessel is grounded to ensure safety, and the bus conductor 83 or the load conductor 84 is connected to the vacuum. If insulation breakdown occurs with the container 94, a ground fault will occur, so it is essential to ensure withstand voltage performance. The bus-side conductor 83 and the load-side conductor 84 are usually made of copper or a copper alloy, and have a low dielectric strength with respect to the vacuum vessel 94. Therefore, a sufficient insulation distance is required. Become something. Since the flexible conductor 88 is also made of a conductive foil or a thin wire, the electric field is easily concentrated, a sufficient insulation distance is required to ensure the withstand voltage, and the vacuum container 94 becomes large. .

The present invention has been made in view of such circumstances, and has as its object to provide a switchgear which is excellent in withstand voltage, ensures safety, and can be downsized.

[0011]

A switchgear according to a first aspect of the present invention includes a bus conductor and a load conductor in a vacuum vessel, and the bus conductor and the load conductor are covered with a stainless steel cover. It is characterized by having. The bus-side conductor and the load-side conductor are made of copper or a copper alloy.In this switchgear, since the conductor is covered with a stainless steel cover having a lower conductivity than copper, the conductor between the conductor and the vacuum vessel is The withstand voltage is improved, and the insulation distance can be shortened.

A switchgear according to a second aspect of the present invention supports a bus-side conductor having a fixed electrode provided at a distal end thereof, a load-side conductor, and a movable electrode in a vacuum vessel, and attaches the movable electrode to the fixed electrode. An operating member to be brought into contact with and separated from the movable electrode, and a flexible conductor connecting the movable electrode and the load-side conductor are provided, and the flexible conductor is covered with a stainless steel cover.
Since the flexible conductor is made of conductive foil or fine wire,
The electric field tends to concentrate, but in this switchgear, the flexible conductor is covered with a stainless steel cover, so the electric field is reduced, the withstand voltage between the flexible conductor and the vacuum vessel is improved, and the insulation is improved. The distance can be shortened.

The switchgear according to a third aspect of the present invention is the switchgear according to the first or second aspect, wherein at least a part or all of an outer surface of the cover or an inner surface of the vacuum vessel facing the outer surface of the cover is provided.
It is characterized by being covered with a substance having lower conductivity than stainless steel. In this switchgear, the withstand voltage is further improved, so that the insulation distance can be shortened.

According to a fourth aspect of the present invention, there is provided a switchgear including a bus-side conductor and a load-side conductor in a vacuum vessel, wherein an outer surface of the bus-side conductor and the load-side conductor, or an inner surface of the vacuum vessel facing the same. It is characterized in that at least one part or the whole is covered with a lower conductivity than copper. In this switchgear, the bus-side conductor and the load-side conductor, or the inner surface of the vacuum vessel opposed thereto, are directly covered with a substance having low conductivity, so that the withstand voltage between the conductor and the vacuum vessel is improved, and the insulation is improved. The distance can be shortened.

According to a fifth aspect of the present invention, there is provided a switchgear for supporting a bus-side conductor provided with a fixed electrode at a distal end, a load-side conductor, and a movable electrode in a vacuum vessel, and attaching the movable electrode to the fixed electrode. An operating member to be brought into contact with and separated from the movable electrode, a flexible conductor for connecting the movable electrode and the load-side conductor, and at least a part or at least one of an outer surface of the flexible conductor, or an inner surface of the vacuum vessel opposed thereto The entirety is covered with a substance having lower conductivity than copper. In this switchgear, since the outer surface of the flexible conductor or the inner surface of the vacuum vessel facing the flexible conductor is directly covered with a substance having low conductivity, the withstand voltage between the flexible conductor and the vacuum vessel is improved, and the insulation is improved. The distance can be shortened.

The switchgear according to the sixth invention is the switchgear according to the third invention, the fourth invention or the fifth invention, wherein the substance having low conductivity is Ti, Cr, Ni, Mo, Ta, W, or a carbide or nitride thereof. It is characterized by being a thing. In this switchgear, the withstand voltage is further improved, and the insulation distance can be shortened.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, the present invention will be specifically described with reference to the drawings showing the embodiments.
FIG. 1 is a side sectional view showing a configuration of a main part of a switchgear according to a first embodiment of the present invention. This switchgear is
A main circuit switch that performs an opening / closing operation between the bus-side conductor 3 and the load-side conductor 4 is configured inside a stainless steel vacuum vessel 14 maintained at a high vacuum. A bus-bar-side conductor 3 made of copper or copper alloy is used to cover one end wall of the vacuum vessel 14 with a bushing 10.
, And the outer end is connected to a bus (not shown). An inner end of the bus-side conductor 3 forms a fixed electrode 3a, and a fixed contact 1 is fixed to a tip of the fixed electrode 3a. The busbar-side conductor 3 is a stainless steel cover 1 extending from the end face of the bushing 10 toward the fixed contact 1.
8 covered. The end of the cover 18 is in contact with the end surface of the bushing 10 in a state where the busbar-side conductor 3 passes through a hole provided at the center thereof. The load-side conductor 4 made of copper or copper alloy penetrates through the load-side conductor introduction portion 14b provided on the peripheral wall of the vacuum vessel 14 via the bushing 11, and its outer end is connected to a power transmission cable to a load (not shown). Have been. Similarly to the bus-side conductor 3, the load-side conductor 4 has an end abutting on the end face of the bushing 11 and is covered by a stainless steel cover 19 extending toward the tip of the load-side conductor 4.

An operation rod 5 is supported by an operation rod introduction portion 14 a provided on the other end wall of the vacuum vessel 14 via a bellows 12 so as to be movable in the axial direction, and extends inside the vacuum vessel 14. The movable electrode 6 is connected to the end of the operation rod 5 via a connecting member 15 with its distal end substantially coaxially butted with the fixed electrode 3a. The movable contact 2 is fixed to the tip of the movable electrode 6, and the inner end of the load-side conductor 4 is connected to the fixed member 7 joined in the middle of the movable electrode 6 via the flexible conductor 8. ing.

On the peripheral wall of the load-side conductor introduction portion 14b, a grounding conductor introduction portion 14c is provided in parallel with the operation rod introduction portion 14a.
The grounding conductor 9 is supported by the grounding conductor introduction portion 14c via the bellows 13 so as to be movable in the axial direction. A movable contact 9 is provided at the tip of the grounding conductor 9.
The fixed contact 4a is fixed to the peripheral surface of the load-side conductor 4 so as to face the movable contact 9a.
The outer end of the grounding conductor 9 is grounded.

The outer end of the operating rod 5 is connected to an operating mechanism (not shown), and the operating rod 5 is moved in the axial direction according to the operation of the operating mechanism. The grounding conductor 9 is also moved in the axial direction by an operation mechanism (not shown).

By moving the operating rod 5 upward from the state shown in FIG. 1, the movable contact 2 is pressed through the connecting member 15 and the movable electrode 6 to come into contact with the fixed contact 1 to close the circuit. Is obtained. At this time, the fixed contact 4a of the load side conductor 4 and the movable contact 9a of the grounding conductor 9 are separated from each other. The main circuit current from a bus (not shown)
It flows to the movable electrode 6 via the busbar-side conductor 3, the fixed contact 1 and the movable contact 2, and is further sent to a power transmission cable (not shown) via the fixed member 7, the flexible conductor 8 and the load-side conductor 4. On the other hand, in this closed state, the operating rod 5
Is moved, the movable contact 2 is separated from the fixed contact 1, an open circuit state is obtained, and the main circuit current from the bus-side conductor 3 to the load-side conductor 4 is cut off. At this time, by moving the grounding conductor 9 in the upward direction in the figure, the movable contact 9a is brought into contact with the fixed contact 4a of the load-side conductor 4 to ensure safety.

In the switchgear of the first embodiment, the copper- or copper-alloy bus-side conductor 3 and the load-side conductor 4 are made of stainless steel covers 18 and 1 having a lower conductivity than copper.
9, the withstand voltage between the bus-side conductor 3, the load-side conductor 4 and the vacuum vessel 14 is improved. Therefore, dielectric breakdown is prevented and the insulation distance can be shortened, so that the vacuum vessel 14 can be downsized.

Embodiment 2 FIG. FIG. 2 is a side sectional view showing a configuration of a main part of a second embodiment of the switchgear according to the present invention. In the figure, the same parts as those of the switchgear of FIG. 1 are denoted by the same reference numerals. In this switchgear, the cover 18 is joined to the bus-side conductor 3 without any gap by brazing or the like, and the cover 19 is joined to the load-side conductor 4 without any gap by brazing or the like. Therefore, the mechanical strength of the bus-side conductor 3 and the load-side conductor 4 is improved, so that the diameter of these conductors can be reduced, and the vacuum vessel 14 can be further downsized.

Embodiment 3 FIG. FIG. 3 is a side sectional view showing a configuration of a main part of a third embodiment of the switchgear according to the present invention. In the figure, the same parts as those of the switchgear of FIG. 1 are denoted by the same reference numerals. In this switchgear, an end of the load-side conductor 4 is fitted into the end, and a stainless steel cover 16 covering the flexible conductor 8 for a predetermined length;
It has a larger diameter, and has a stainless steel cover 17 that covers the flexible conductor 8 and a part of the cover 16 by fitting the peripheral surface of the fixing member 7 into the end. Since the flexible conductor 8 is made of a conductive foil or a thin wire, the electric field is easily concentrated. However, the electric field is reduced by being covered with the covers 16 and 17, and the withstand voltage is improved. Therefore, the insulation distance can be shortened, and the vacuum vessel 14 can be downsized.

Embodiment 4 FIG. 4 is a side sectional view showing a configuration of a main part of a fourth embodiment of the switchgear according to the present invention. In the figure, the same parts as those of the switchgear of FIG. 1 are denoted by the same reference numerals. In this switchgear, the outer surface of the cover 18 and the inner surface of the vacuum vessel 14 opposed thereto,
And the outer surface of the cover 19 and the vacuum vessel 1 opposed thereto
4, a high withstand voltage material layer 20 is provided. The high withstand voltage material layer 20 is provided on the outer surface of the cover 18 and the inner surface of the vacuum vessel 14 with T.sub.
It can be obtained by plating or spraying i, Cr, Ni, Mo, Ta, W, or a carbide or nitride thereof. As compared with the switchgear according to the first embodiment, the withstand voltage between busbar-side conductor 3, load-side conductor 4 and vacuum vessel 14 is further improved, so that the insulation distance can be further shortened, and the vacuum The size of the container 14 can be reduced.

Embodiment 5 FIG. 5 is a side sectional view showing a configuration of a main part of a fifth embodiment of the switchgear according to the present invention. In the figure, the same parts as those of the switchgear of FIG. 1 are denoted by the same reference numerals. In this switchgear, the outer surfaces of the covers 16 and 17 and the
Is provided with a high withstand voltage material layer 20 on the inner surface thereof. The high withstand voltage material layer 20 is formed on the outer surfaces of the covers 16 and 17 and the inner surface of the vacuum vessel 14 facing the covers 16 and 17 by using Ti, Cr, Ni, Mo, Ta, W, or a carbide thereof having a lower conductivity than stainless steel. Alternatively, it can be obtained by plating or spraying a nitride or the like. Since the withstand voltage between the flexible conductor 8 and the vacuum container 14 is further improved as compared with the switch gear according to Embodiment 3, the vacuum container 14 can be further downsized.

Embodiment 6 FIG. FIG. 6 is a side sectional view showing a configuration of a main part of a sixth embodiment of the switchgear according to the present invention. In the figure, the same parts as those of the switchgear of FIG. 1 are denoted by the same reference numerals. In this switchgear, the high withstand voltage material layer 2 is formed on the peripheral surfaces of the busbar-side conductor 3, the load-side conductor 4, and the flexible conductor 8 and the inner surface of the vacuum vessel 14 facing these.
Is 1 provided? The high withstand voltage material layer 21 is formed on the peripheral surface and the inner surface with Ti, C having a lower conductivity than copper.
It can be obtained by plating or spraying r, Ni, Mo, Ta, W, or a carbide or nitride thereof.
By providing the high withstand voltage material layer 21, the withstand voltage between the busbar-side conductor 3, the load-side conductor 4, the flexible conductor 8 and the vacuum vessel 14 is improved, so that the insulation distance can be shortened. The size of the vacuum container 14 can be reduced.

In the fourth, fifth and sixth embodiments, Ti, Cr, Ni, Mo, T
Although a case where a, W, or a carbide or nitride thereof is used has been described, the present invention is not limited to this, and another material may be used. However, it is preferable to use the above-mentioned substance in consideration of the withstand voltage.

[0029]

As described in detail above, according to the switchgear of the first invention, the bus-side conductor and the load-side conductor made of copper or copper alloy are covered with a stainless steel cover having a lower conductivity than copper. Therefore, the withstand voltage between the conductor and the vacuum container is improved. Therefore, insulation breakdown is prevented and safety is ensured, so that the insulation distance can be shortened, the vacuum vessel can be downsized, and the switchgear can be made compact.

According to the switchgear according to the second aspect of the present invention, since the flexible conductor made of conductive foil or fine wire is covered with the stainless steel cover, the electric field is alleviated, and the flexible conductor and the vacuum container are reduced. Withstand voltage between them is improved. Therefore,
The insulation distance can be shortened, and the size of the switchgear can be reduced.

According to the switchgear according to the third invention, in the first invention or the second invention, at least one part or all of the outer surface of the cover or the inner surface of the vacuum vessel opposed to the cover is made of stainless steel. Since it is covered with a substance having low conductivity, the withstand voltage is further improved. Therefore, the insulation distance can be further reduced, and the size of the switchgear can be further reduced.

According to the switchgear of the fourth aspect, at least one of the bus-side conductor and the load-side conductor, or at least one of the inner surfaces of the vacuum vessel opposed thereto, is directly covered with a substance having low conductivity, so that the withstand voltage is improved. I do. Therefore, the insulation distance can be shortened, and the size of the switchgear can be reduced.

According to the switchgear according to the fifth aspect, at least one of the outer surface of the flexible conductor or the inner surface of the vacuum container facing the flexible conductor is directly covered with a material having low conductivity, so that the withstand voltage is improved. Therefore, the insulation distance can be shortened, and the size of the switchgear can be reduced.

According to the switchgear according to the sixth aspect, the substance having low conductivity is composed of Ti, Cr, Ni, Mo, Ta,
W, or a carbide or nitride thereof, further improves the withstand voltage property. Therefore, the insulation distance can be further reduced, and the size of the switchgear can be further reduced.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a configuration of a main part of a first embodiment of a switchgear according to the present invention.

FIG. 2 is a side sectional view illustrating a configuration of a main part of a second embodiment of the switchgear according to the present invention.

FIG. 3 is a side sectional view showing a configuration of a main part of a third embodiment of the switchgear according to the present invention.

FIG. 4 is a side sectional view showing a configuration of a main part of a fourth embodiment of the switchgear according to the present invention.

FIG. 5 is a side sectional view showing a configuration of a main part of a fifth embodiment of the switchgear according to the present invention.

FIG. 6 is a side sectional view showing a configuration of a main part of a sixth embodiment of the switchgear according to the present invention.

FIG. 7 is a side sectional view showing a configuration of a main part of a conventional switchgear.

FIG. 8 is a side sectional view showing a configuration of a main part of a conventional switchgear.

[Explanation of symbols]

3 busbar side conductor, 4 load side conductor, 5 operation rod, 6
Movable electrode, 8 flexible conductor, 9 grounding conductor, 14 vacuum vessel, 18, 19 cover, 20, 21 high withstand voltage material layer.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Minoru Maruyama 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Toshifumi Sato 2-3-2 Marunouchi, Chiyoda-ku, Tokyo 3 Rishi Electric Co., Ltd. (72) Inventor Minoru Kobayashi 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Tomotaka Yano 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric F term in reference (reference) 5G017 AA21 BB01 BB03 BB07 5G026 EA01 EB02

Claims (6)

[Claims] 1. A switchgear comprising a bus conductor and a load conductor in a vacuum vessel, wherein the bus conductor and the load conductor are covered with a stainless steel cover. 2. An operation member for supporting a bus-side conductor provided with a fixed electrode at a distal end thereof, a load-side conductor, and a movable electrode in a vacuum vessel, and bringing the movable electrode into and out of contact with the fixed electrode, A switch gear, comprising: a flexible conductor that connects the movable electrode and the load-side conductor; and the flexible conductor is covered with a stainless steel cover. 3. The method according to claim 1, wherein at least a part or the whole of the outer surface of the cover or the inner surface of the vacuum vessel facing the cover is covered with a substance having a lower conductivity than stainless steel. Switchgear. 4. A vacuum vessel includes a bus-side conductor and a load-side conductor, and a part or all of at least one of the outer surfaces of the bus-side conductor and the load-side conductor, or at least one of the inner surfaces of the vacuum vessel facing these. Characterized by being covered with a substance having lower conductivity than copper. 5. An operating member for supporting a bus-side conductor provided with a fixed electrode at a distal end thereof, a load-side conductor, and a movable electrode in a vacuum vessel, and bringing the movable electrode into and out of contact with the fixed electrode, A flexible conductor for connecting the movable electrode and the load-side conductor, wherein at least a part or all of the outer surface of the flexible conductor, or at least one of the inner surfaces of the vacuum vessel opposed thereto, has a conductivity higher than that of copper. A switchgear characterized by being covered with a low-substance substance. 6. The low-conductivity substance is Ti, Cr,
6. The switchgear according to claim 3, wherein the switchgear is Ni, Mo, Ta, W, or a carbide or nitride thereof.