JP3455471B2 - Gas insulated switchgear - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas insulated switchgear used in a power system.

[0002]

2. Description of the Related Art FIG. 6 shows, for example, Japanese Patent Laid-Open Publication No. 8-
An example of a tulip contactor of a disconnector, which is an opening / closing contactor of a conventional gas-insulated switchgear described in No. 203364, is shown. 13 is a tulip contactor, 14 is a movable contactor,
Reference numeral 14a denotes a plated layer of the movable contactor 14, 15 denotes a fixed contact piece, and a large number of fixed contact pieces 15 form a fixed contact piece. 15a is a plating layer of the fixed contact piece 15, 16
Is a conductor, 17 is a mounting bracket, 18 is a fixing bolt, 19 is a supporting bracket, and 20 is a garter spring.

Next, the operation will be described. In FIG. 6, the tulip contactor 13 arranged in a container (not shown) in which the insulating gas of the disconnector of the gas insulated switchgear is sealed.
On the sliding contact surfaces of the fixed contact piece 15 and the movable contact 14 of FIG.
5a and 14a are provided to reduce the contact resistance. The plating layers 15a and 14a plated with silver or silver composite have a thickness of 50 to 200 μm.
m. Fixed contact piece 15 of tulip contact piece 13
And the sliding contact of the movable contact 14 causes the plating layers 15a and 14a to slide, and the sliding wear causes silver abrasion powder having a thickness of the plating layer or a thickness close to the thickness of the plating layer, and the surface of the insulator or the gas insulation. Accumulates on the inner surface of the container of the switchgear, causing insulation deterioration. Further, since the silver layers of the plating layers 15a and 14a are mechanically attached to the copper ingots of the fixed contact piece 15 and the movable contact 14, they are peeled off when a large load is applied and the silver having a length of several mm is peeled off. Stripping occurs, resulting in a greater insulation loss of the disconnector.

Furthermore, when the gas-insulated switchgear is a circuit breaker, the sliding speed of the contact is much higher than that of the disconnector, and a large silver piece of about several millimeters is produced to insulate the circuit breaker of the gas-insulated switchgear. It tends to decrease. This is because the adhesion between the silver plating layer and the copper of the base metal is weak, and the thickness of the silver plating layer is large. Further, in the conventional gas-insulated switchgear, it is necessary to clean the silver-plated powder worn after the initial break-in operation, and it is also necessary to clean the silver-plated powder generated during the operation during the regular inspection after the operation for a predetermined period. However, extra work is required and the cost is increased accordingly.

[0005]

Since the conventional gas-insulated switchgear has the above-mentioned structure, abrasion powder is generated from the silver-plated layer of the switchgear, which deteriorates the insulation performance, and the initial and regular intervals. There were problems such as high inspection costs. In order to make the gas-insulated electrical equipment including the gas-insulated switchgear compact, an insulating gas such as SF6 gas, which has high insulation strength, is enclosed in the insulating space to reduce the insulating dimension. Therefore, the adverse effects of the above-mentioned abrasion powder are more remarkable than in the case of air insulation having a large insulation dimension.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a gas-insulated switchgear in which abrasion powder is less likely to be generated by the opening / closing operation of an opening / closing contact.

[0007]

According to a first aspect of the present invention, there is provided a gas-insulated switchgear according to claim 1, wherein a metal of an opening / closing contact is made of copper or a copper alloy, and an outer surface of at least one of the opening / closing contact has an outer surface .
To form a surface layer having a thickness of 0.5~10μm made of the base metal and silver alloy by introducing silver component from those above closing contacts is to slide on this surface layer is there. A gas-insulated switchgear according to a second aspect of the present invention is the gas insulated switchgear according to the first aspect, wherein a protective layer made of a silver-plated layer having a thickness of 5 to 20 μm is formed on the surface layer. The gas-insulated switchgear according to claim 3 is the gas-insulated switchgear according to claim 1 or 2, wherein the opening / closing speed of the opening / closing contactor is 2 to 20 m / s.
It is what The gas-insulated switchgear according to claim 4 is the gas insulated switchgear according to any one of claims 1 to 3, wherein the component of the surface layer is such that the ratio of silver increases from the metal side toward the surface. It is a thing.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1. An embodiment of the present invention will be described below. FIG. 1 is a sectional view of a disconnector which is a gas-insulated switchgear according to the present embodiment,
FIG. 2 is a sectional view of the movable contactor. 1 and 2, 1 is a disconnector, 2 is a movable contactor, 2a is a copper alloy metal of the movable contactor 2, and 2b is a surface layer of the movable contactor 2 and a fixed contactor (described later). On the sliding surface, that is, the surface of the movable contact 2, is formed of an alloy layer of copper and silver having a thickness of 0.5 to 10 μm. 3 is a fixed contactor, 3a is a fixed contactor 3
Copper alloy base metal 3b is a surface layer of the fixed contactor 3,
On the sliding surface with the movable contact 2, that is, on the surface of the fixed contact 3, an alloy layer of copper and silver having a thickness of 0.5 to 10 μm is formed. The movable contact 2 and the fixed contact 3 can be contacted and separated from each other 2
It constitutes one open / close contact. Reference numeral 4 is a finger contact, 5 and 6 are conductor parts on the movable side and a fixed side, 7 is an insulating cylinder, 8 and 9 are metal shields, 10 is an insulating space, and the above 1 to 9 are housed in a metal container (not shown). An insulating medium such as SF6 gas is enclosed in the metal container.

The surface layers 2b and 3b of the movable contactor 2 and the fixed contactor 3 are made of copper fine particles of the bare metal 2a and 3a by an ion cluster beam method, and silver fine particles are electrically charged in a high vacuum. It is manufactured by accelerating and applying at a high speed to form an alloy layer of the copper alloy and silver on the base metal 2a, 3a.
The hardness of the alloy layers, that is, the surface layers 2b and 3b is higher than the hardness of the base metal. There is also a method using this ion cluster beam method to form a silver layer on the surface of the metal, but in this case the surface hardness is comparable to silver and high hardness cannot be obtained, so an alloy layer is formed. It is necessary to manufacture under the conditions. In addition to the ion cluster beam method, it can be manufactured by, for example, an ion implantation method, a CVD method, or the like.

Next, the operation will be described. In FIG. 1, the disconnector 1 is in an open state, the movable contactor 2 moves to the right, contacts the fixed contactor 3, and slides on the inner surface of the fixed contactor 3 at a predetermined closed state fixed position. Stop. Also, the disconnector 1
The opening operation of is the opposite. That is, the movable contact 2
In FIG. 1, it moves to the left and slides on the inner surface of the fixed contactor 3, and is separated from the fixed contactor 3 to be in an open state. The outer surface layer 2b of the movable contactor 2 and the inner surface layer 3 of the fixed contactor 3
Since b is in contact therewith and that part contains silver, the contact resistance is small and it withstands the temperature rise due to energization. The surface layers 2b and 3b, which are sliding surfaces, have a high hardness, and a thin contact grease is applied to the sliding surfaces of the movable contact 2 and the fixed contact 3 to prevent seizure due to sliding. In the above example, the metal 2a, 3a
Although a copper alloy was used, even if copper is used instead of the copper alloy, the same effect can be obtained by forming an alloy layer of copper and silver as the surface layers 2b and 3b. In either case, the composition ratio of silver in the alloy layers which are the surface layers 2b and 3b is 20 to 99%.
And If the silver component is too small, the contact resistance will increase,
On the contrary, if the amount is too large, the hardness becomes small, which is a problem.

In FIGS. 1 and 2, the disconnecting switch 1 has a high hardness of the sliding surfaces of the movable contact 2 and the fixed contact 3 even after a large number of operations, so that the movable contact 2 and the fixed contact 3 have a high hardness. The amount of abrasion powder caused by sliding is extremely small. This is because the Vickers hardness of silver is about 26, while the Vickers hardness of the alloy layers of the surface layers 2b and 3b of the movable contact 2 and the fixed contact 3 is about 100, which is significantly high. Further, it is also caused by the fact that when the silver particles are applied to the copper alloy by the ion cluster beam method, the hardness is further increased due to the surface hardening phenomenon of the copper alloy.

FIG. 3 is a graph showing the relationship between the contact opening / closing speed and the contact wear amount. The curve A shows the case of silver plating (thickness 50 μm) as in the conventional case, and the curve B shows an example of an alloy of silver and copper. The amount of wear per 100 times of closing and closing is compared. The unit PU on the vertical axis means that the former amount of wear at low speed is expressed as 1.
As can be seen from FIG. 3, when the sliding speed of the contact exceeds 2 m / s, the amount of wear tends to increase significantly with silver plating, and the amount of wear tends to change little with alloys of silver and copper. This is because, in the case of silver-plated contacts having a high sliding speed, the silver plating is peeled off due to the load when the contacts hit each other. On the other hand, in the case of a silver-copper alloy contactor having a high sliding speed, peeling and abrasion are less likely to occur due to the hardness of the alloy layer and the high adhesion strength with the base metal.

In FIG. 1, the surface layer 2b of the movable contact 2 is shown.
Is formed by the ion cluster beam method, but it is the most suitable method for forming a thin alloy layer on the surface of a processed copper alloy, and other methods form a silver-copper alloy layer with good surface accuracy. Is difficult to do. The formation of a silver-copper alloy layer with good surface accuracy is a particularly excellent effect of the ion cluster beam method in which silver ionized in a high vacuum is applied to the copper alloy surface at high speed.

In FIG. 1, a disconnector is shown as an example of the gas-insulated switchgear, but it can also be applied to a circuit breaker. Circuit breaker
Although it is used at a switching speed of 2 to 20 m / s, in the case of a circuit breaker with a significantly higher switching speed, as shown in FIG.
As shown in (1), the amount of abrasion powder generated is greatly reduced compared to the conventional one, and it becomes more effective in terms of improving the insulation reliability of the gas-insulated switchgear and reducing the maintenance cost. The same effect can be obtained in the case of other gas-insulated switchgear such as a gas-insulated ground switch.

In FIG. 2, the thickness of the surface layers 2b and 3b is as thin as 0.5 to 10 μm, but since the amount of wear is small, the bare metals 2a and 3a are exposed even after a large number of operations, for example, several thousand times or more. The low contact resistance due to the silver component can be maintained for a long period of time. Even if the surface layers 2b and 3b shown in FIG. 2 are partially thickened, the same effect can be obtained without any trouble. In addition, although the surface layer is formed on both the movable contact 2 and the fixed contact 3 in the structure shown in FIG. 1, even if one side has a slightly increased amount of wear, a similar effect equivalent to that of one side can be obtained. . Further, the surface layers 2b, 3b may be made to be a graded alloy layer so that the components of the surface layers 2b, 3b increase the ratio of silver from the side of the metal 2a, 3a toward the surface.
As a result, the degree of adhesion between the surface layers 2b and 3b and the base metals 2a and 3a is increased.

Embodiment 2. Hereinafter, another embodiment of the present invention will be described. FIG. 4 is a cross-sectional view of the movable contactor of the disconnector which is the gas-insulated switchgear according to the present embodiment. In the figure, 2c is a silver plating layer which is a protective layer formed on the surface layer 2b and has a thickness of 5 to 20 μm. Others are the same as in the case of the first embodiment, and therefore description thereof will be omitted.

The manufacturing method of the movable contactor 2 shown in FIG.
As in the case of FIG. 2, fine silver particles are electrically accelerated in a high vacuum and applied at high speed to the surface of the copper alloy ingot 2a by the ion cluster beam method, and the alloy of the ingot 2a and silver is applied to the surface. A layer having a thickness of 0.5 to 10 μm is formed as a surface layer 2b, and a silver plating layer 2c similar to the conventional one is formed on the surface layer 2b.
Is as thin as 5 to 20 μm. The surface layer 2b made of an alloy of the metal 2a and silver having a thickness of 10 μm or less is slightly scratched depending on the handling, and the metal 2a is partially exposed on the surface. When stored for a long time in the air, a copper oxide or a copper sulfide may be generated to increase the contact resistance. In order to prevent this oxidation or sulfidation, a thin silver plating layer 2c for protecting the surface is provided. Has been. This silver plating layer 2c is
Compared with the conventional film thickness of the silver plating layer of 50 to 200 μm, 5
Since the thickness is as thin as ˜20 μm, even if abrasion or peeling occurs due to a large number of operations, it becomes fine silver powder of 20 μm or less, and does not affect the insulation of the gas insulated switchgear so much. After the silver plating layer 2c is worn, it operates in the same manner as in the first embodiment. Therefore, by applying thin silver plating, it is effective in improving the long-term reliability of gas-insulated electrical equipment. The thickness of the protective layer 2c is set to 5 to 20 μm because if it is too thick, the silver abrasion powder becomes large and adversely affects the insulation performance, and if it is too thin, it cannot serve as a protective layer. Although the silver plating layer 2c is formed on the surface layer 2b of the movable contact 2 in the above, it may be formed on the surface layer of the fixed contact or on both of them.

Embodiment 3. Hereinafter, still another embodiment of the present invention will be described. FIG. 5 is a cross-sectional view of the movable contactor of the disconnector which is the gas-insulated switchgear according to the present embodiment. The surface layer 2b is formed only on the front end portion of the movable contactor 2 and a part of the surface subsequent thereto. Others are the same as in the case of the first embodiment, and therefore description thereof will be omitted. In the case of the movable contactor 2 of FIG. 5, the surface layer 2b is partially formed by the ion cluster beam method.
Since the area of b is significantly smaller than that in the case of FIG. 2, the manufacturing cost can be greatly reduced and the economical efficiency can be improved as compared with the movable contactor 2 of FIG.

[0019]

As described above, according to the gas-insulated switchgear according to claim 1 of the present invention, the surface layer made of an alloy of metal and silver is formed on the surface of the metal of the switching contact. Further, the hardness of the surface of the switching contact becomes high, and abrasion powder due to the sliding of both contacts is less likely to occur, which improves the insulation reliability of the gas-insulated switchgear and reduces the maintenance cost.

Further, according to the gas-insulated switchgear according to the second aspect, since the protective layer formed by silver plating is formed on the surface layer of the switching contact, the surface is protected during storage and copper is not oxidized or sulfurized. To prevent. Further, according to the gas-insulated switchgear according to the third aspect, since it is applied to a high-speed switch having an opening / closing speed of 2 to 20 m / s, the wear amount of the opening / closing contact can be significantly reduced as compared with the conventional one. Further, according to the gas-insulated switchgear according to claim 4, since the component of the surface layer is such that the ratio of silver increases from the metal side toward the surface, the degree of adhesion between the surface layer and the metal is high. Become.

[Brief description of drawings]

FIG. 1 is a sectional view of a disconnector according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a movable contactor of the disconnector of FIG.

FIG. 3 is a graph showing the relationship between the amount of wear and the opening / closing speed of the movable contact of the gas insulated switchgear according to the present invention.

FIG. 4 is a sectional view of a movable contactor of a disconnector according to Embodiment 2 of the present invention.

FIG. 5 is a sectional view of a movable contactor of a disconnector according to a third embodiment of the present invention.

FIG. 6 is a sectional view showing an opening / closing contact of a conventional opening / closing device.

[Explanation of symbols]

2 movable contactor, 2a ingot of movable contactor, 2b surface layer of movable contactor, 3 fixed contactor, 3a ingot of fixed contactor, 3b surface layer of fixed contactor, 2c silver plating layer.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01H 1/02 H01H 1/38 H02B 13/02

Claims (4)

(57) [Claims] 1. A gas-insulated switchgear in which two opening / closing contacts which can be slidably contacted and separated from each other are mounted in a metal container, and an insulating gas is enclosed in the metal container. By forming an alloy and introducing a silver component from the outside onto the surface of at least one of the open and closed contacts
To form a surface layer having a thickness of 0.5~10μm made of the base metal and silver alloy, gas insulated switchgear, characterized in that the opening and closing contacts in the surface layer was made to slide. 2. A protective layer made of a silver-plated layer having a thickness of 5 to 20 μm is formed on the surface layer.
Gas-insulated switchgear described. 3. The opening / closing speed of the opening / closing contactor is 2 to 20 m / s.
The gas-insulated switchgear according to claim 1 or 2, wherein 4. The gas-insulated switchgear according to claim 1, wherein the component of the surface layer is such that the proportion of silver increases from the metal side toward the surface. .