JPH11262120A - Electric field relaxing apparatus and electric apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an electric field strength and to reduce the size by changing the permittivity of an insulating layer, so as to decrease successively from one electrode side to the other electrode side. SOLUTION: The permittivity of the whole insulating layer is changed in stages so as to decrease from one-end electrode 15 side to the other-end electrode 15 side. Incidentally. the movable contact of a disconnector 4 is operated, by linking an operating board 11 to the end electrode 15 with a linking pin 12, and converting the rotating motion of the operating board 11 into horizontal motion by the linking pin 12. Potential gradation in the insulating layer becomes smaller, and an electric field strength around the end electrode 15 lowers, by changing the permittivity of the whole insulating layer in stages, so as to decrease from the one-end electrode 15 side to the other-end electrode 15 side, in an electric field relaxing apparatus. Especially on the surface of the end electrode 15, its electric field strength lowers by the influence of the insulating layer. Consequently, it becomes possible to reduce the size of the electric field relaxing apparatus itself, by suppressing the electric field strength of the end electrode 15, and the electric file strength of the insulating layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric field mitigation device for suppressing electric field strength of electrodes such as main circuit conductors used for electric equipment such as gas insulated switchgear, and more particularly to a miniaturized electric field mitigation device. It is about. In addition, the present invention relates to an electric device such as a gas-insulated switchgear, and particularly to an electric device in which storage devices are rationally arranged to reduce the size.

[0002]

2. Description of the Related Art FIG. 7 is a schematic diagram showing a configuration example of a gas insulated switchgear which is a typical electric device. In FIG. 7, a circuit breaker 2, a connection conductor 3, a disconnector 4, a connection conductor 5, a cable head 6, an insulator 7, a busbar are provided inside a sealed container 1 in which an insulating gas such as SF ₆ gas is sealed at substantially atmospheric pressure. 8
Are stored and required wiring is made.

[0003] Here, the insulating gas is an electrically negative gas, and the breakdown voltage depends on the electric field strength. That is, specifically, a structure is adopted in which the radius of curvature of the electrode is increased to eliminate the electric field concentration portion.

As an electric field relaxation for suppressing the radius of curvature, for example, there is a composite insulating structure as shown in a sectional view of a main part in FIG. For example, as disclosed in Japanese Patent Application Laid-Open No. 2-46111, the insulating layer 1 formed by molding an epoxy resin on the end electrode 9 of the movable contact of the disconnector 4 is disclosed.
0 is provided.

On the other hand, the operating plate 11 is connected to the end electrode 9 of the movable contact of the disconnector 4 by a connecting pin 12, and converts the rotational movement into a linear movement by an operating mechanism (not shown).

Here, the end electrode 9 is provided with a curved portion 9a to suppress the electric field intensity at a portion (hereinafter, referred to as a triple junction portion) 13 in contact with the insulating layer 10.
In other words, the triple junction 13 where the end electrode 9, the insulating layer 10 and the insulating gas are in contact with each other is provided with a curved portion 9 a having a structure for suppressing an electric field on the side of the end electrode 9 because the electric field strength increases. .

Further, between the ground plate 14 and the ground,
The withstand voltage is improved by actions such as electric field relaxation and electron emission suppression by the insulating layer 10. Thereby, the insulating layer 10
It has high withstand voltage characteristics with a small radius of curvature and is reduced in size.

[0008]

By the way, in such a configuration, the insulating layer 10 is molded with an epoxy resin, and the dielectric constant ε is about 5 = ε. When the dielectric constant is higher than the dielectric constant (about 1) of the insulating gas, the outer diameter of the curved portion 9a must be increased in order to suppress the electric field of the triple junction portion 13.

That is, the triple junction section 13
Is arranged so as to be covered by the curved portion 9a, the electric field strength can be largely suppressed. However, this
The diameter direction of the end electrode 9 including the curved portion 9a becomes large.

In the direction between the ground and the ground, the electric field intensity is determined by the potential sharing between the gas gap and the insulating layer 10.
For this reason, when the dielectric constant of the insulating layer 10 is large, the potential sharing of the gas gap increases, and the electric field intensity increases accordingly.

Accordingly, although the gas gap and the insulating thickness of the insulating layer 10 are optimized to minimize the potential sharing, the maximum electric field is located in the gas gap and the withstand voltage is determined. As described above, since the dielectric constant of the insulating layer 10 is larger than the dielectric constant of the insulating gas, there is a limit to the size for relaxing the electric field, which goes against the recent trend of miniaturization. .

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electric field moderating device capable of suppressing the electric field intensity and achieving downsizing. It is a further object of the present invention to provide an electric device capable of reducing the size by arranging storage devices rationally.

[0013]

According to a first aspect of the present invention, there is provided an electric field relaxation device provided at an end of an electrode and comprising an insulating layer for suppressing electric field strength of the electrode. The dielectric constant of the insulating layer is changed so as to gradually decrease from the electrode side to the opposite electrode side.

Here, in particular, the insulating layer is made of an epoxy resin, and the amount of the filler mixed with the epoxy resin is reduced from the electrode side to the opposite electrode side. It is preferable that the dielectric constant of the insulating layer be changed continuously or stepwise by changing the dielectric constant of the insulating layer.

Therefore, in the electric field relaxation device according to the first and second aspects of the present invention, the electric potential in the insulating layer is changed by gradually changing the dielectric constant of the insulating layer from the electrode side to the opposite electrode side. The sharing is reduced, and the electric field strength around the electrodes is reduced. In particular, at the electrode surface where the electrode is in contact with the insulating layer, the electric field strength is reduced due to the influence of the insulating layer.

Thus, the electric field intensity of the electrode and the electric field intensity of the insulating layer can be suppressed, and the size of the electric field relaxation device itself can be reduced. On the other hand, in the invention of claim 3, in the electric field relaxation device provided at the end of the electrode and suppressing the electric field strength of the electrode, a projection having a semicircular cross section is provided at the end of the electrode in the circumferential direction. A first insulating layer made of an insulating material having a predetermined dielectric constant is provided so as to cover the protruding portion and the end of the electrode, and a dielectric constant higher than the insulating material is provided on the outer periphery of the first insulating layer. A second insulating layer made of an insulating material having a small thickness.

Here, for example, it is preferable that the insulation thickness of the second insulation layer is larger than the insulation thickness of the first insulation layer. Further, for example, as set forth in claim 5, the insulation distance of the electrode is 100 m.
m, the insulating thickness of the first insulating layer is 5
mm, and the insulating thickness of the second insulating layer is preferably 40 mm.

Therefore, in the electric field relaxation device according to the third to fifth aspects of the present invention, the first insulating layer having a large dielectric constant is provided on the end of the electrode on the electrode side, and is provided on the outer periphery of the first insulating layer. ,
By providing the second insulating layer having a smaller dielectric constant than the first insulating layer, the electric field strength of the electrode and the electric field strength of the insulating layer can be suppressed, and the size of the electric field relaxation device itself can be reduced.

The potential distribution of the second insulating layer is increased by increasing the insulating thickness and decreasing the dielectric constant of the first insulating layer. Along with this, the potential allotment of the gas gap decreases, and as a result, the electric field strength of the gas gap, which affects the breakdown voltage, decreases.

As a result, the withstand voltage characteristic of the electric field relaxation device itself is improved, and the size of the electric field relaxation device itself can be further reduced. According to a sixth aspect of the present invention, in the electric field relaxation device according to any one of the third to fifth aspects, the first and second insulating layers are formed of epoxy resin. The compounding amount of the filler mixed with the epoxy resin forming the second insulating layer is smaller than the compounding amount of the filler mixed with the epoxy resin forming the insulating layer.

Therefore, in the electric field relaxation device according to the present invention, the mixing amount of the filler mixed with the epoxy resin forming the first insulating layer is more than the mixing amount of the filler mixed with the epoxy resin forming the second insulating layer. By reducing the amount of the filler to be mixed, the electric field strength of the electrode and the electric field strength of the insulating layer can be suppressed, and the size of the electric field relaxation device itself can be reduced.

According to a seventh aspect of the present invention, in the electric field relaxation device according to any one of the third to fifth aspects, the first insulating layer is formed of an epoxy resin and the second insulating layer is formed of an epoxy resin. The layer is formed of an insulating material made of Teflon resin or crosslinked polyethylene.

Therefore, in the electric field relaxation device according to the present invention, the first insulating layer is formed of an epoxy resin having a large dielectric constant, and the second insulating layer has a smaller dielectric constant than the first insulating layer. By using Teflon resin or cross-linked polyethylene, the electric field strength of the electrode and the electric field strength of the insulating layer can be suppressed, and the size of the electric field relaxation device itself can be reduced.

According to the invention of claim 8, in the above-mentioned claim 3,
8. The electric field relaxation device according to claim 1, wherein a male screw is formed on one of the first insulating layer and the second insulating layer and the other is screwed with the male screw. Is formed.

Therefore, in the electric field relaxation device according to the present invention, a male screw is formed on one of the first insulating layer and the second insulating layer, and a female screw screwed with the male screw is formed on the other. By forming, even the second insulating layer made of an insulating material having poor adhesion to the first insulating layer can be easily attached and fixed, so that stable mechanical characteristics can be obtained. .

Further, according to a ninth aspect of the present invention, in the electric field relaxation device according to any one of the third to seventh aspects, a male or female member is provided on one of the first insulating layer and the second insulating layer. In addition to forming a screw, a female screw to be screwed with a male screw is formed on the other, and a silicone grease layer is provided at an interface between the first insulating layer and the second insulating layer.

Therefore, in the electric field relaxation device according to the ninth aspect of the present invention, a male screw is formed on one of the first insulating layer and the second insulating layer, and a female screw screwed with the male screw is formed on the other. By forming and further providing a silicone grease layer at an interface between the first insulating layer and the second insulating layer, the first insulating layer and the second insulating layer can be combined with each other. Since the interface gap is filled with a thin film of silicone grease,
Stable insulation characteristics can be obtained.

On the other hand, according to the invention of claim 10, the first conductor provided with an insulating layer serving as an electric field relaxation layer at the end is housed in a closed container filled with an insulating gas such as SF ₆ gas. In the configured electric device, a stepped opening hole for conductor connection is provided substantially at right angles to the axial direction of the first conductor,
A second conductor having a step corresponding to the opening is connected to the opening of the first conductor.

Therefore, in the electric device according to the tenth aspect of the present invention, the first conductor provided with the insulating layer is provided with a stepped opening for connecting the conductor substantially at right angles to the axial direction. By connecting the second conductor to the hole, it is possible to arrange the second conductor substantially at a right angle. Therefore, the conductor can be arranged rationally and the overall shape of the electric device can be reduced.

According to the eleventh aspect of the present invention, the first conductor provided with an insulating layer serving as an electric field relaxation layer at an end is housed in a closed container filled with an insulating gas such as SF ₆ gas. In the configured electric device, a stepped opening hole for conductor connection is provided substantially at right angles to the axial direction of the first conductor,
A center conductor (second conductor) of the bushing is passed through the opening of the first conductor to the step of the opening.

Here, for example, as described in claim 12, it is preferable that the bushing is a gas-air bushing, and a conductor connecting portion is provided on the gas-side central conductor (second conductor).

Preferably, a third conductor from another direction is connected to the first conductor, for example. Therefore, Claim 11 to Claim 1
In the electric device according to the third aspect of the present invention, a stepped opening for conductor connection is provided substantially perpendicularly to the axial direction in the first conductor provided with the insulating layer, and the center conductor ( By penetrating the second conductor), it is possible to arrange the conductor at a substantially right angle with the shortest bending radius from the end of the bushing. Can be planned.

According to a fourteenth aspect of the present invention, in the electric device according to any one of the tenth to thirteenth aspects, the dielectric constant of the insulating layer provided at the end of the first conductor is set to It is changed so as to become smaller sequentially from the first conductor side to the anti-first conductor side.

Therefore, in the electric device according to the present invention, the dielectric constant of the insulating layer provided at the end of the first conductor is gradually reduced from the first conductor side to the anti-first conductor side. , The potential distribution in the insulating layer is reduced, and the electric field strength around the first conductor is reduced. In particular, on the surface of the first conductor where the first conductor is in contact with the insulating layer, the electric field strength is reduced due to the influence of the insulating layer.

Thus, the electric field strength of the first conductor and the electric field strength of the insulating layer can be suppressed, and the overall shape of the electric device can be further reduced. Furthermore, in the invention according to claim 15, a disconnector having a movable contact that changes the rotational movement of the operation plate into a horizontal movement by a connecting pin is provided by SF
_{(6) In an} electric device configured to be housed inside a closed container filled with an insulating gas such as a gas, the electrode end on the operation plate side of the movable contact of the disconnector has a predetermined dielectric constant. A first insulating layer made of an insulating material is provided, and a second insulating layer made of an insulating material having a smaller dielectric constant than the insulating material is provided around the first insulating layer.

Therefore, in the electric device according to the fifteenth aspect of the present invention, the movable contact of the disconnector has an electrode end on the operation plate side.
A first insulating layer having a higher dielectric constant is provided on the electrode side, and a second insulating layer having a lower dielectric constant than the first insulating layer is provided around the first insulating layer.
By providing the insulating layer, the electric field strength of the electrode and the electric field strength of the insulating layer can be suppressed, and the size of the electric field relaxation device itself can be reduced.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to an electric field relaxation device provided at an end of an electrode and comprising an insulating layer for suppressing the electric field strength of the electrode, wherein the dielectric constant of the insulating layer is changed from the electrode side to the opposite electrode side. It is changed so as to become smaller sequentially.

Hereinafter, embodiments of the present invention based on the above concept will be described in detail with reference to the drawings. (First Embodiment) FIG. 1 is a cross-sectional view of an essential part showing a configuration example of an electric field relaxation device at a main circuit conductor end according to the present embodiment, and the same parts as those in FIG. The description thereof will be omitted, and only different portions will be described here.

That is, in the electric field relaxation device of the present embodiment, as shown in FIG. 1, the end electrode 15 is provided with a ring portion 15a having a semicircular cross section in the circumferential direction. First portion so as to cover the portion 15a and the end electrode 15
And the second insulating layer 17 is provided on the outer periphery of the first insulating layer 16.

Here, the first insulating layer 16 is made of an insulating material having a large dielectric constant, and is formed by molding with an epoxy resin, for example. When the insulation distance T of the end electrode 15 is 100 mm or more, the first insulation layer 16 is formed with an insulation thickness of, for example, about 5 mm.

The second insulating layer 17 is made of an insulating material having a lower dielectric constant than the insulating material of the first insulating layer 16. For example, a large amount of filler is mixed to suppress the dielectric constant.
It is made of epoxy resin, Teflon resin, cross-linked polyethylene, or the like.

When the insulation distance T of the end electrode 15 is 100 mm or more, the second insulation layer 17
The insulating layer 16 is formed with an insulating thickness of about 40 mm, which is larger than the insulating thickness of the insulating layer 16 and is about half of the gas gap length.

In this case, in the epoxy resin, for example, by filling a large amount of silica powder as a filler,
The size of the dielectric constant can be set to 4 or less, and for example, by filling a milled fiber as a filler,
The magnitude of the dielectric constant can be 5 or more.

As described above, the dielectric constant of the entire insulating layer is changed stepwise so as to decrease from the end electrode 15 side to the opposite end electrode 15 side. In addition, the operation plate 11 is connected to the end electrode 15 by the connection pin 12 and
The movable contact of the disconnector 4 is operated by changing the rotational movement of the disconnector 4 into a horizontal movement by the connecting pin 12.

Next, in the electric field relaxation device of the present embodiment configured as described above, the dielectric constant of the entire insulating layer is reduced stepwise from the end electrode 15 side to the opposite end electrode 15 side. In this case, the potential distribution in the insulating layer is reduced, and the electric field intensity around the end electrode 15 is reduced.

In particular, on the surface of the end electrode 15 where the end electrode 15 is in contact with the insulating layer, the electric field strength is reduced due to the influence of the insulating layer. Thereby, the electric field strength of the end electrode 15,
In addition, the electric field intensity of the insulating layer can be suppressed, and the electric field relaxation device itself can be reduced in size.

Further, the second insulating layer 17 has a larger insulating thickness and a lower dielectric constant than the first insulating layer 16, so that the potential sharing is increased. Along with this, the potential allotment of the gas gap decreases, and as a result, the electric field strength of the gas gap, which affects the breakdown voltage, decreases.

Thus, the withstand voltage characteristic of the electric field relaxation device itself is improved, and the electric field relaxation device itself can be further reduced in size. FIG. 2 is a characteristic diagram showing an electric field intensity distribution of the electric field relaxation device when the insulating thickness of the first insulating layer 16 is changed.

In FIG. 2, a curve E ₁ (solid line) represents the electric field intensity at the point A on the end electrode 15 side of the triple junction, and a curve E ₂ (dotted line) represents the electric field intensity of the outer second insulating layer 17. This is the electric field intensity at point B on the side where the maximum electric field intensity changes under the influence of the inner first insulating layer 16 on the surface.

The condition used here is that the dielectric constant of the first insulating layer 16 is 5.9 and the second insulating layer 1
7, the magnitude of the dielectric constant is 2.7, and the insulation thickness is constant at 45 mm.

From the characteristic curve shown in FIG. 2, at the point where the insulation thickness is about 5 mm, the electric field strength on the surface of the end electrode 15 and the electric field strength on the surface of the second insulating layer 17 intersect. From this, it can be seen that this is the condition in which the electric field intensity is most suppressed.

That is, under such conditions, the withstand voltage characteristic of the electric field relaxation device is most improved, and the overall shape of the electrode can be reduced. (Second Embodiment) FIG. 3 is a cross-sectional view of a main part showing an example of a configuration example of an electric field relaxation device at a main circuit conductor end according to the present embodiment (in a case where insulating layers are separately manufactured and attached). .

That is, in the electric field relaxation device of this embodiment, as shown in FIG. 3, the end electrode 18 is provided with a ring portion 18a having a semicircular cross section in the circumferential direction. A first insulating layer 19 made of an insulating material having a large dielectric constant is provided by molding so as to cover the portion 18 a and the end electrode 18, and a first insulating layer 19 is formed on the outer periphery of the first insulating layer 19. The second insulating layer 21 made of an insulating material having a smaller dielectric constant than the insulating material described above is provided by molding.

In this case, a male screw is formed on one side of either the first insulating layer 19 or the second insulating layer 21, and a female screw is formed on the other side to be screwed with the male screw. In advance, the male screw (or female screw) of the first insulating layer 19
Then, by screwing a female screw (or a male screw) of the second insulating layer 21, the second insulating layer 21 is attached to the first insulating layer 19.
Is fixed.

Further, at the interface between the first insulating layer 19 and the second insulating layer 21, a silicone grease layer 23 is provided to improve the adhesion. FIG. 4 is a cross-sectional view of a main part showing another configuration example of the electric field relaxation device at the end of the main circuit conductor according to the present embodiment (in the case where the insulating layers are separately manufactured and attached). Are denoted by the same reference numerals.

That is, in the electric field relaxation device of the present embodiment, as shown in FIG. 4, a ring portion 18a having a semicircular cross section is provided in the end electrode 18 in the circumferential direction. A first insulating layer 20 made of an insulating material having a large dielectric constant is molded and provided so as to cover the portion 18 a and the end electrode 18, and a first insulating layer 20 is formed around the outer periphery of the first insulating layer 20. And a second insulating layer 22 made of an insulating material having a smaller dielectric constant than the insulating material described above.

In this case, a male screw is formed at the bottom of one of the first insulating layer 20 and the second insulating layer 22, and a female screw is formed at the other bottom to be screwed with the male screw. And the male screw (or female screw) of the first insulating layer 20
Then, a female screw (or a male screw) of the second insulating layer 22 is screwed into the first insulating layer 20 so that the second insulating layer 22
Is fixed.

Further, at the interface between the first insulating layer 20 and the second insulating layer 22, a silicone grease layer 23 is provided to improve the adhesion. In FIG. 4, the first
Although the screw portion of the first insulating layer 20 is a convex portion, even if the screw portion of the first insulating layer 20 is a concave portion,
Any shape can be used as long as it can be closely fitted and fixed.

Next, in the electric field relaxation device according to the present embodiment shown in FIGS.
The first insulating layer 19 is formed by forming a male screw on one of the insulating layers 19 and 20 and the second insulating layer 21 and 22 and forming a female screw for screwing with the male screw on the other. ,
Even with the second insulating layer made of an insulating material having poor adhesion to the second insulating layer 20, stable mechanical characteristics can be obtained because the second insulating layer can be easily attached and fixed.

Further, since the silicone grease layer 23 is provided at the interface between the first insulating layers 19 and 20 and the second insulating layers 21 and 22, the first insulating layers 19 and 20 and the second
The gap at the interface with the insulating layers 21 and 22 is filled with a thin film of silicone grease, so that stable insulating characteristics can be obtained.

Further, by separately molding the first insulating layers 19 and 20 and the second insulating layers 21 and 22, compared to the case where the molding is performed a plurality of times,
Opportunities to create defects specific to the mold, such as voids and peeling, can be reduced. Thus, an insulating layer with few defects can be formed, and productivity can be improved.

(Third Embodiment) FIG. 5 shows a configuration example of a main circuit conductor end of a gas insulated switchgear which is an electric device according to the present embodiment (when conductors are connected at substantially right angles). It is principal part sectional drawing.

That is, in the gas insulated switchgear of this embodiment, as shown in FIG. 5, the first conductor 24 which is an electrode provided with an insulating layer serving as an electric field alleviating layer at the end is made of SF ₆ gas or the like. In an electric device configured to be housed inside a sealed container in which the insulating gas is sealed, a ring portion 24a having a semicircular cross section is provided at an end of the first conductor 24 in a circumferential direction. The ring portion 24a and the first conductor 24
A first insulating layer 25 made of an insulating material having a large dielectric constant is molded and provided so as to cover the end portion, and is further provided around the outer periphery of the first insulating layer 25 than the insulating material of the first insulating layer 25. A second insulating layer 26 made of an insulating material having a small dielectric constant is provided, and an electric field relaxation device is provided.

Further, a stepped opening hole 24b for connecting a conductor is provided substantially at right angles to the axial direction of the first conductor 24. On the other hand, the second conductor 27 is provided with a stepped portion corresponding to the opening hole 24b to form a stepped portion, and a contact 28 made of, for example, a multi-band is provided. By doing so, the second conductor 27 is connected to the opening 24 b of the first conductor 24.

Next, in the electric device of the present embodiment configured as described above, a stepped opening hole 24b for connecting a conductor is provided in the first conductor 24 substantially at right angles to the axial direction. Since the second conductor 27 is connected to the opening hole 24b, the second conductor 27 can be arranged substantially at a right angle. The size can be reduced.

That is, even if the conductors are arranged at substantially right angles,
The electric field strength at the bent portion can be suppressed by the first insulating layer 25 and the second insulating layer 26. For this reason, conventionally, when a conductor was bent at a right angle, the radius of curvature of the bent portion had to be larger than the mechanical characteristics and insulating characteristics. Since the conductors can be arranged at right angles, rational arrangement can be performed, and accordingly, the overall shape of the electric device can be reduced.

Further, the dielectric constant of the insulating layer provided at the end of the first conductor 24 is changed from the first conductor 24 side to the anti-first conductor 24 side by forming the insulating layers into two layers 25 and 26. , The potential distribution in the insulating layer is reduced, and the first conductor 24
The surrounding electric field strength decreases. In particular, on the surface of the first conductor 24 where the first conductor 24 is in contact with the insulating layer, the electric field strength is reduced due to the influence of the insulating layer.

As a result, the electric field strength of the first conductor 24,
In addition, the electric field strength of the insulating layer is suppressed, so that the overall shape of the electric device can be further reduced. (Fourth Embodiment) FIG. 6 is a cross-sectional view of an essential part showing a configuration example of a main circuit conductor end of a gas insulated switchgear which is an electric device according to the present embodiment (when a conductor is attached to a bushing at a right angle). It is a figure and the same code | symbol is attached | subjected and shown to the same element as FIG.

That is, in the gas insulated switchgear of this embodiment, as shown in FIG. 6, the first conductor 33 which is an electrode provided with an insulating layer serving as an electric field relaxation layer at the end is made of SF ₆ gas or the like. In an electric device configured to be housed inside a sealed container filled with an insulating gas, a ring portion 33a having a semicircular cross section is provided at an end of the first conductor 33 in a circumferential direction. The ring portion 33a and the first conductor 33
A first insulating layer 25 made of an insulating material having a large dielectric constant is molded and provided so as to cover the end portion, and is further provided around the outer periphery of the first insulating layer 25 than the insulating material of the first insulating layer 25. A second insulating layer 26 made of an insulating material having a small dielectric constant is provided, and an electric field relaxation device is provided.

Further, a stepped opening hole 33b for connecting a conductor is provided substantially at right angles to the axial direction of the first conductor 33. On the other hand, a gas-air bushing 31 is air-tightly fixed to the board wall 30, and the central conductor (the second conductor) of the gas-air bushing 31 is inserted into the opening 33 b of the first conductor 33.
Of the gas-in-air bushing 31 in the opening hole 33b of the first conductor 33 by passing the conductor 32 through the stepped portion of the opening hole 33b to the stepped portion of the opening hole 33b and then fixing it with a bolt 29 via a contact 28. The conductor 32 is connected at a substantially right angle on the gas side.

Next, in the electric device of the present embodiment configured as described above, the first conductor 33 is provided with the stepped opening hole 33b for connecting the conductor substantially at right angles to the axial direction. The gas-air bushing 31 is inserted into the opening 33b.
Of the center conductor 32 of the bushing 31, it is possible to arrange the first conductor 33 almost at a right angle with the shortest bending radius from the end of the bushing 31. The overall shape can be reduced.

Further, the electric field relaxation device at the end of the first conductor 33 is formed of the second insulating layer 26 having a small dielectric constant also on the surface of the gas-air bushing 31 along the insulating layer. An increase in strength can be suppressed.

Therefore, the gas-air bushing 31 can be reduced in size as compared with the case where a metal shield is used in the electric field relaxation device, and the overall shape of the electric equipment can be further reduced. be able to.

(Other Embodiments) As another embodiment other than the above, not only the connection of the conductors in two directions as described in the third or fourth embodiment but also the connection in three directions, etc. Even when connecting conductors from multiple directions, the above-mentioned insulating layer is formed at the ends of the conductors, and by providing the connection portions, the conductors are similarly arranged rationally and the overall shape of the electric device is reduced. Can be achieved.

[0075]

As described above, according to the first to ninth aspects of the present invention, there is provided an electric field relaxation device including an insulating layer provided at an end of an electrode and suppressing the electric field strength of the electrode. Since the dielectric constant of the layer is changed so as to gradually decrease from the electrode side to the opposite electrode side, an electric field relaxation device capable of suppressing the electric field strength of the electrode and the electric field strength of the insulating layer to achieve a reduction in size is provided. Can be provided.

Further, according to the tenth to fifteenth aspects of the present invention, the first structure in which an insulating layer serving as an electric field relaxation layer is provided at an end portion.
Is provided with a stepped opening hole for connecting the conductor substantially at right angles to the axial direction of the first conductor in an electric device configured to house the conductor in an airtight container filled with an insulating gas. Since the conductors from other directions are inserted and connected to the opening holes, it is possible to provide an electric device capable of arranging the storage devices rationally and reducing the size.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a first embodiment of an electric field relaxation device for a main circuit conductor end according to the present invention.

FIG. 2 is a characteristic diagram showing an electric field intensity distribution when an insulating thickness of a first insulating layer is changed in the electric field relaxation device according to the first embodiment.

FIG. 3 is a cross-sectional view of a main part showing a second embodiment of the electric field relaxation device at the end of the main circuit conductor according to the present invention.

FIG. 4 is an essential part cross-sectional view showing a second embodiment of an electric field relaxation device for a main circuit conductor end according to the present invention.

FIG. 5 is an essential part cross-sectional view showing a third embodiment of a main circuit conductor end of an electric device (gas insulated switchgear) according to the present invention.

FIG. 6 is an essential part cross-sectional view showing a fourth embodiment of a main circuit conductor end of an electric device (gas insulated switchgear) according to the present invention.

FIG. 7 is a schematic diagram showing a configuration example of a gas insulated switchgear which is a typical electric device.

FIG. 8 is a cross-sectional view of a main part showing a configuration example of an electric field relaxation device at a main circuit conductor end according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Closed container, 2 ... Circuit breaker, 3 ... Connection conductor, 4 ... Disconnector, 5 ... Connection conductor, 6 ... Cable head, 7 ... Insulator, 8 ... Busbar, 9, 15, 18 ... End electrode, 10 ... Insulating layer, 11: operation plate, 12: connecting pin, 13: triple junction portion, 14: ground plate, 16, 19, 20, 25: first insulating layer, 17, 21, 22, 26: second insulation 23, silicone grease layer, 24, 33 ... first conductor, 27 ... second conductor, 28 ... contact, 29 ... bolt, 30 ... board wall, 31 ... gas-air bushing, 32 ... gas- Central conductor of air bushing 31.

Claims (15)

[Claims] 1. An electric field relaxation device provided at an end of an electrode and comprising an insulating layer for suppressing the electric field strength of the electrode, wherein the dielectric constant of the insulating layer decreases gradually from the electrode side to the opposite electrode side. An electric field relaxation device characterized by being changed to: 2. The electric field relaxation device according to claim 1, wherein the insulating layer is formed of an epoxy resin, and a compounding amount of a filler mixed with the epoxy resin is reduced from the electrode side to the opposite electrode side. By changing to become
An electric field relaxation device wherein the dielectric constant of the insulating layer is changed continuously or stepwise. 3. An electric field relaxation device provided at an end of an electrode for suppressing an electric field intensity of the electrode, wherein a protrusion having a semicircular cross section is provided at an end of the electrode in a circumferential direction. A first insulating layer made of an insulating material having a predetermined dielectric constant so as to cover the portion and the end of the electrode; An electric field relaxation device comprising a second insulating layer made of an insulating material having a low rate. 4. The electric field relaxation device according to claim 3, wherein the insulation thickness of the second insulation layer is larger than the insulation thickness of the first insulation layer. . 5. The electric field relaxation device according to claim 4, wherein when the insulation distance of the electrode is 100 mm or more, the insulation thickness of the first insulation layer is 5 mm, and the insulation thickness of the second insulation layer is 5 mm. An electric field relaxation device characterized in that the insulation thickness of the device is 40 mm. 6. The method according to claim 3, wherein
The electric field relaxation device according to claim, wherein the first and second insulating layers are formed of an epoxy resin, and the amount of the filler mixed with the epoxy resin forming the first insulating layer is more than the compounding amount of the filler. An electric field relaxation device characterized in that the amount of a filler mixed with an epoxy resin for forming a second insulating layer is reduced. 7. The method according to claim 3, wherein
The electric field relaxation device according to claim 1, wherein the first insulation layer is formed of an epoxy resin, and the second insulation layer is formed of an insulation material made of Teflon resin or crosslinked polyethylene. . 8. The method according to claim 3, wherein
The electric field relaxation device according to claim, wherein a male screw is formed in one of the first insulating layer and the second insulating layer, and a female screw that is screwed with the male screw is formed in the other. Electric field relaxation device. 9. The method according to claim 3, wherein
The electric field relaxation device according to claim, wherein a male screw is formed on one of the first insulating layer and the second insulating layer, and a female screw that is screwed with the male screw is formed on the other. An electric field relaxation device, wherein a silicone grease layer is provided at an interface between the first insulating layer and the second insulating layer. 10. An electric apparatus comprising: a first conductor provided with an insulating layer serving as an electric field relaxation layer at an end thereof, in a closed container in which an insulating gas such as SF ₆ gas is sealed. An opening having a step is provided substantially at right angles to the axial direction of the first conductor, and a second conductor having a step portion corresponding to the opening is connected to the opening of the first conductor. An electrical device characterized by comprising: 11. An electric apparatus comprising: a first conductor provided with an insulating layer serving as an electric field relaxation layer at an end thereof, in a sealed container in which an insulating gas such as SF ₆ gas is sealed. A stepped opening hole is provided substantially at right angles to the axial direction of the first conductor, and a center conductor (second conductor) of a bushing is inserted in the opening hole of the first conductor to a step portion of the opening hole. An electric device characterized by being penetrated. 12. The electric device according to claim 11, wherein the bushing is a gas-air bushing, and a conductor connection portion is provided on a center conductor (second conductor) on the gas side. Electrical equipment. 13. The electric device according to claim 11, wherein the first conductor is connected to a third conductor from another direction. 14. The electric device according to claim 10, wherein a dielectric constant of an insulating layer provided at an end of the first conductor is:
An electric field relaxation device characterized by being changed so as to become smaller sequentially from the first conductor side to the anti-first conductor side. 15. A disconnector having a movable contact for changing the rotational movement of the operation plate into a horizontal movement by a connecting pin is provided by SF ₆
In an electric device configured to be housed in a sealed container filled with an insulating gas such as a gas, the movable contact of the disconnector has an electrode end on a side of an operation plate of a movable contact having a predetermined dielectric constant. A first insulating layer made of an insulating material is provided, and a second insulating layer made of an insulating material having a smaller dielectric constant than the insulating material is provided around the first insulating layer. Electrical equipment.