JPH09294325A - Gas insulation bus bar - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-sized gas insulation bus bar capable of absorbing specified thermal shrinkage and expansion well, having a simple shunt shape, and excellent in profitability. SOLUTION: A bellows 3 for absorbing thermal shrinkage and expansion is inserted into and fitted to a part of a container 2 for a gas insulation bus bar 1. Between shunt seats 4a, 4b provided on containers 2a, 2b on both sides of the bellows 3, an in-phase shunt 10 for causing a sheath current to flow is provided. The in-phase shunt 10 is arranged in the axial direction of the containers 2a, 2b, and the shunt seats 4a, 4b and the in-phase shunt 10 are provided in the horizontal direction at the center parts on both sides of the containers 2a, 2b and the bellows 3. The shape of the cross section of the in- phase shunt 10 is a trapezoid composed of obtusely bent parts 10a, 10b at both end parts and a parallel part 10c in their center part. One end of the bellows 3 is insulated from the container 2a by an insulating ring 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated bus bar used in a power transmission and transformation system, and more particularly to a gas-insulated bus bar having a bellows that absorbs thermal expansion and contraction.

[0002]

2. Description of the Related Art A gas-insulated bus bar has a structure in which a conductor is housed in a container in which an insulating gas is sealed and the conductor is supported by an insulator with respect to the container. Since this gas-insulated bus bar is placed outdoors, the container expands and contracts due to temperature changes due to solar radiation, changes in the temperature of the outside air, heat generation of the current flowing through the conductor, and the like. Against the thermal expansion and contraction of such a container, FIG.
As shown in (C) to (C), a bellows 3 for absorbing thermal expansion and contraction is inserted in a part of the container 2 of the gas-insulated busbar 1. 9A is a front view, FIG. 9B is a side view, and FIG. 9C is a plan view. In FIG. 9, a pressure-balancing type expandable bellows is used as the bellows 3.

The container 2 of the gas-insulated bus bar 1 is generally made of aluminum, and a sheath current due to the main circuit energization flows through the container made of aluminum. On the other hand, since the bellows 3 is mainly made of stainless steel and its resistivity is higher than that of the container 3 made of aluminum, the temperature rise due to the energization of the sheath current cannot be suppressed low. From this,
As shown in FIG. 9C, the containers 2 on both sides of the bellows 3 are provided.
Shunt seats 4a and 4b are provided on a and 2b, respectively, and an in-phase shunt 5 made of copper or aluminum for passing a sheath current is provided between the shunt seats 4a and 4b. In this case, the in-phase shunt 5 is arranged in the axial direction of the containers 2a and 2b as shown in FIG. 9 (A), and the shunt seat 4 as shown in FIG. 9 (B).
The a, 4b and the in-phase shunt 5 are horizontally provided at the central portions in the vertical direction on both sides of the containers 2a, 2b and the bellows 3. Further, as shown in FIGS. 9A and 9C, one end of the bellows 3 is insulated from the container 2a by an insulating ring 6 so that a sheath current does not flow through the bellows 3. In addition, in the gas-insulated busbar 1 installed in a snowy region, as shown in FIG. 9B, a snow cover 7 is attached to the upper part of the bellows 3 to protect the bellows 3.

In the gas-insulated bus bar 1 as described above, both ends of the in-phase shunt 5 have flanges 3 a of the bellows 3.
Bent at right angles to avoid interference with
a, 5b are formed. However, as shown in the load vector diagram of FIG. 10, the load F generated in the axial direction of the in-phase shunt 5 due to the displacement Δx due to the thermal expansion and contraction of the containers 2a and 2b is such that the right-angled bent portion 5a,
5b without generating a load F1 in the direction (F1 =
0), all of them act on the right-angled bent portions 5a and 5b.
In order to reduce such stress concentration on the right-angled bent portions 5a, 5b, a U-shaped bent portion 5d is formed in the parallel portion 5c between the right-angled bent portions 5a, 5b of the in-phase shunt 5 which is parallel to the bellows 3. It is provided at one place or a plurality of places (three places in the figure) and is given a spring property. Further, the in-phase shunt 5 can absorb the thermal expansion and contraction of the containers 2a and 2b satisfactorily due to the elasticity of the U-shaped bent portion 5d.

[0005]

However, in the conventional gas-insulated bus bar 1 configured as described above, the container 2
As a and 2b become longer and the amount of expansion and contraction thereof increases, the U-shaped bent portion 5d of the parallel portion 5c of the in-phase shunt 5 increases.
The number of Therefore, the in-phase shunt 5 has a complicated shape, and the gas-insulated busbar 1 is not only large in size, but also disadvantageous in terms of material, processing, and the like in terms of cost.

Further, in the case where the bellows 3 itself has a long length, such as a pressure-balancing type expandable bellows as shown in FIG. 9, a device such as a switch disposed around the gas-insulated bus bar 1 is used. Although the in-phase shunt 5 vibrates during operation, the parallel portion 5c of the in-phase shunt 5 has a U-shaped bent portion 5d, which makes it difficult to support the shunt in the parallel portion 5c.

Further, as shown in FIG. 9, when the snow cover 7 is attached to the upper portion of the bellows 3, the U-shaped bent portion 5d of the in-phase shunt 5 is housed inside the snow cover 7, so that the snow cover 7 is housed. 7 has a large size, and as a result, the entire gas-insulated bus bar 1 has a large size.

The present invention has been proposed in order to solve the above-mentioned problems of the prior art, and its purpose is to:
An object of the present invention is to provide a small-sized gas-insulated busbar that can absorb predetermined thermal expansion and contraction, has a simple shunt shape, and is excellent in economy.

[0009]

According to a first aspect of the present invention, a conductor is housed in a container in which an insulating gas is sealed.
In a gas-insulated busbar having a bellows provided in a part of the container to absorb thermal expansion and contraction, and a common-phase shunt that connects the containers on both sides of the bellows and flows a sheath current,
The cross-sectional shape of the in-phase shunt is characterized by a trapezoidal shape having obtuse-angled bent portions at both ends thereof.

According to the invention described in claim 1 having the above-mentioned structure, the cross-sectional shape of the in-phase shunt is formed into a trapezoidal shape having obtuse-angled bent portions at both ends, so that the container is displaced by thermal expansion and contraction. The load generated in the in-phase shunt can be shared by both the obtuse-angled bent portions at both ends and the parallel portion therebetween. Therefore, it is possible to reduce the stress concentration at the bending portion of the in-phase shunt, and it is possible to favorably absorb the predetermined thermal expansion and contraction. Moreover, since it is not necessary to provide a U-shaped bent portion in the parallel portion of the in-phase shunt, it is possible to simplify the shape of the in-phase shunt and downsize the entire gas-insulated busbar.

The invention described in claim 2 is characterized in that, in the gas-insulated bus bar according to claim 1, the following intermediate support portion is provided. That is, the intermediate support portion is provided between a part of a parallel portion parallel to the bellows in a central portion of the in-phase shunt and a part of a central portion of the bellows facing the same, and the intermediate support portion is the same as the bellows. It is configured to support an interphase shunt. The intermediate support portion has an insulating member that electrically insulates between the sheath of the bellows and the in-phase shunt.

According to the second aspect of the present invention having the above-described structure, a part of the parallel portion of the central portion of the in-phase shunt is supported by the intermediate support portion against the bellows, so that the gas-insulated bus bar is formed. Since it is possible to suppress vibrations during operation of a switch or the like arranged around the switch and to reduce radial displacement of the in-phase shunt, it is possible to reduce the size of the entire gas-insulated bus bar. By electrically insulating the sheath of the bellows and the in-phase shunt with an insulating member, a sheath current does not flow in the bellows, so that the sheath current-carrying performance of the in-phase shunt is not impaired.

According to a third aspect of the present invention, in the gas-insulated bus bar according to the second aspect, the intermediate supporting portion has a supporting member, a long hole, and a bolt as described below. That is, the support member is configured to be attached to the bellows to support the in-phase shunt. The elongated hole is provided in the parallel portion of the in-phase shunt so as to extend in the axial direction. The bolt is provided so as to pass through the elongated hole of the in-phase shunt, and radially supports the in-phase shunt so that the in-phase shunt can move in the axial direction with respect to the support member. .

According to the third aspect of the present invention having the above-mentioned structure, by the elongated hole provided in the parallel portion of the in-phase shunt and the bolt penetrating the elongated hole to support the in-phase shunt. The in-phase shunt can be supported in the radial direction while being slidable in the axial direction with respect to the bellows. Therefore, it is possible to reduce the stress concentration at the bolt fastening portion between the in-phase shunt and the intermediate support portion, and it is possible to favorably absorb the predetermined thermal expansion and contraction.

According to a fourth aspect of the invention, in the gas-insulated bus bar according to the third aspect, the support seat surface of the bolt of the intermediate support portion is spherical. According to a fifth aspect of the invention, in the gas-insulated bus bar according to the third aspect, a washer for supporting the in-phase shunt is attached to the bolt of the intermediate support portion, and a support seat surface of the washer is a spherical surface. It is characterized by its shape.

According to the inventions of claims 4 and 5 having the above-mentioned structure, the supporting seat surface for supporting the in-phase shunt is formed into a spherical shape, so that the in-phase shunt and the intermediate support portion are formed. Since the stress concentration in the bolt fastening portion can be further reduced and the relative movement between the elongated hole and the bolt or washer can be performed more smoothly, it is possible to better absorb the predetermined thermal expansion and contraction.

According to a sixth aspect of the invention, in the gas-insulated bus bar according to any one of the first to fifth aspects, the in-phase shunt is arranged below the bellows. According to the sixth aspect of the present invention having the above-described configuration, the in-phase shunt is arranged at the lower part of the bellows, so that when the snow cover is attached to the upper part of the bellows, the in-phase shunt is placed inside the snow cover. Since it is not necessary to store the snow cover in a small size,
As a result, the entire gas-insulated bus bar can be downsized.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A plurality of embodiments of a gas insulated bus bar according to the present invention will be specifically described below with reference to FIGS. The same parts as those of the conventional example shown in FIGS. 9 and 10 are designated by the same reference numerals, and the description thereof will be omitted.

[1. First Embodiment] FIGS. 1 and 2
FIG. 1 is a diagram showing, as a first embodiment of the present invention, one embodiment to which the invention described in claim 1 is applied. (A) of FIG. 1 is a front view and (B) of FIG. Side view,
(C) is a plan view. Further, FIG. 2 is a load vector diagram of the shunt mounting portion.

As shown in FIGS. 1 (A) and 1 (C), in this embodiment, as the bellows 3, a pressure-balance type expandable bellows is used, and the containers 2a on both sides of the bellows 3 are used. An in-phase shunt 10 made of copper or aluminum for passing a sheath current is provided between the shunt seats 4a and 4b provided at 2b. In this case, the in-phase shunt 10 is provided in the container 2 as shown in FIG.
The shunt seats 4a and 4b and the in-phase shunt 10 are arranged in the axial direction of a and 2b, and as shown in FIG. , Is installed horizontally.

Then, as shown in FIG. 1C, obtuse angle bent portions 10a and 10b are formed at both ends of the in-phase shunt 10 instead of the right angle bent portions as shown in FIG. . That is, the cross-sectional shape of the in-phase shunt 10 is
It has a trapezoidal shape composed of obtuse angled bent portions 10a and 10b at both ends and a parallel portion 10c at the center thereof. as a result,
As shown in FIG. 2, the parallel portion 10c of the in-phase shunt 10
Of the obtuse angle bending parts 10a and 10b with respect to the axial direction of
Is 0 ° <θ <90 °. The parts other than the in-phase shunt 10 are configured in exactly the same manner as the conventional example shown in FIG.

In the present embodiment having the above-mentioned structure, as shown in the load vector diagram of FIG.
A part of the load F generated in the axial direction of the in-phase shunt 10 due to the displacement Δx due to the thermal expansion and contraction of a and 2b is equal to the load F1 (F1 = Fcos θ) in the direction along the obtuse angle bending portions 10a and 10b of the in-phase shunt 10. This obtuse angle bending part 10
a, 10b, and the parallel part 1 of the in-phase shunt 10
An axial load F2 (F2 = Fcos ² θ) is generated at 0c. Here, the value of the angle θ is determined in consideration of the flange outer diameter of the bellows 3 and the outer diameters of the containers 2a and 2b. For example, when the angle θ is set to about 45 °, the same phase About 5 of the load F at the parallel part 10c of the shunt 10.
You will have to pay 0%.

Therefore, it is possible to reduce the stress concentration in the obtuse angle bending portions 10a and 10b of the in-phase shunt 10, and it is not necessary to provide the U-shaped bending portion 5d as shown in FIG. It is possible to satisfactorily absorb the predetermined thermal expansion and contraction equivalent to the conventional technique. In this case, since the in-phase shunt 10 has a simple shape, the entire gas-insulated bus bar 1 can be downsized, and it is advantageous in terms of material, processing, and the like in terms of cost.

[2. Second Embodiment] FIGS. 3 and 4
FIG. 4 is a diagram showing, as a second embodiment of the present invention, one embodiment to which the invention described in claim 2 is applied. FIG. 3 is a plan view and FIG. 3 is a detailed view of an A portion of FIG. 3, (B) is a front view of (A). Since the present embodiment basically has the same configuration as that of the first embodiment, only the parts different from the first embodiment will be described below.

As shown in FIG. 3, in the present embodiment, an intermediate support portion 20 is provided between a part of the parallel part 10c of the in-phase shunt 10 and a part of the bellows 3 facing the parallel part 10c. The in-phase shunt 10 is supported with respect to the bellows 3. As shown in FIG. 4A, the intermediate support portion 20 has an L-shaped support member 21 and is configured as follows. That is, as shown in FIG. 4A, one end of the support member 21 is attached to the flange tightening stud 3b of the bellows 3 through the insulating washer 22 by using the nut 23, the spring loupe 24, and the flat loupe 25. It is fixed. Further, the other end of the support member 21 is fixed to the parallel portion 10c of the in-phase shunt 10 by using a bolt 26, a nut 27, a spring blade 28, and a flat blade 29. The other parts are constructed in exactly the same manner as in the first embodiment.

In the present embodiment having the above-described structure, the intermediate support portion 20 can easily and reliably support a part of the parallel portion 10c of the in-phase shunt 10 with respect to the bellows 3. As a result, it is possible to suppress vibration during operation of a switch or the like arranged around the gas-insulated bus bar 1. Further, since the radial displacement of the in-phase shunt 10 can be reduced, the size of the gas insulated busbar 1 as a whole can be reduced. Further, since the intermediate support portion 20 has a simple structure using the L-shaped support member 21, the bolt 26 and the nut 27, it is also advantageous in terms of cost. Since the sheath of the bellows 3 and the in-phase shunt 10 are electrically insulated by the insulating washer 22 of the intermediate support portion 20, no sheath current flows through the bellows 3, and therefore the in-phase shunt 10 is not provided. It does not impair the energizing performance of the sheath.

[3. Third Embodiment] FIGS. 5 and 6
FIG. 6 is a diagram showing, as a third embodiment of the present invention, one embodiment to which the invention described in claims 3 and 5 is applied. FIG. 5 is a plan view and FIG. FIG. 6 is a detailed view of an A portion of FIG. 5, and (B) is a front view of (A). Since this embodiment has basically the same configuration as that of the second embodiment, only portions different from the second embodiment will be described below.

As shown in FIG. 5, in the present embodiment, in-phase shunt 1 is provided as in the second embodiment.
The intermediate support portion 20 is provided between a part of the parallel part 10c of 0 and a part of the bellows 3 facing the parallel part 10c.
Against the in-phase shunt 10. As shown in FIG. 6A, this intermediate support portion 20 basically has
It has the same configuration as that of the second embodiment, but the configuration of the fixing portion between the support member 21 and the parallel portion 10c of the in-phase shunt 10 is different. That is, as shown in FIG. 6B, the parallel portion 10c of the in-phase shunt 10 is provided with the elongated hole 31 extending in the axial direction, and as shown in FIG. 6A, the bolt 26 is It is provided so as to penetrate the elongated hole 31. Then, on the support seat surface of the bolt 26,
Instead of the flathead 29, a spherical washer 32 having a spherical support seat surface is provided. This spherical washer 3
2 is attached to the bolt 26 so as to maintain a gap L between the parallel portion 10c of the in-phase shunt 10 and the parallel portion 10c. Further, on the tip side of the bolt 26, a nut 27 and a spring countersunk 28 are provided, as in the second embodiment. The other parts are constructed in exactly the same manner as in the second embodiment.

In the present embodiment having the above-described structure, the long hole 31 provided in the parallel portion 10c of the in-phase shunt 10 and the in-phase shunt 10 penetrating the long hole 31.
The in-phase shunt 10 can be slidably moved in the axial direction with respect to the bellows 3 by a bolt 26 and a spherical washer 32 that support the diametrically supported diametrically.

Therefore, it is possible to reduce the stress concentration at the bolt fastening portion between the in-phase shunt 10 and the intermediate support portion, and it is possible to satisfactorily absorb predetermined thermal expansion and contraction. Especially,
Since the in-phase shunt 10 is supported by the spherical washer 32, the stress concentration at the bolt fastening portion can be further reduced, and the relative movement between the elongated hole 31 and the spherical washer 32 can be performed more smoothly. The predetermined thermal expansion and contraction can be better absorbed.

As a modified example of the present embodiment, it is conceivable to apply the invention of claim 4 to make the seat surface of the bolt 26 spherical. Even in the case of such a configuration, similar operational effects can be obtained.

[4. Fourth Embodiment] FIG. 7 is a diagram showing one embodiment to which the invention according to claim 6 is applied, as a fourth embodiment of the present invention.
(A) is a front view and (B) is a side view. Since the present embodiment basically has the same configuration as that of the first embodiment, only the parts different from the first embodiment will be described below.

As shown in FIG. 7, in the present embodiment, the shunt seats 4a and 4b and the in-phase shunt 10 are provided.
Is arranged diagonally downward at the lower part of the containers 2a, 2b and the bellows 3 in the vertical direction. A snow cover 7 is attached to the upper part of the bellows 3. The other parts are constructed in exactly the same manner as in the first embodiment.

According to the present embodiment having the above-described structure, since the in-phase shunt 10 is arranged below the bellows 3, it is not necessary to store the in-phase shunt 10 inside the snow cover 7. As compared with the case where the in-phase shunt 5 is housed inside the snow cover 7 as in the conventional example shown in FIG. 9, the snow cover 7 can be downsized, and as a result, the entire gas-insulated busbar 1 can be downsized. .

As a modified example of this embodiment, as shown in FIGS. 8A and 8B, the in-phase shunt 10 is provided.
It is conceivable that the bellows 3 is arranged directly below the bellows 3 so as to face downward. Similar effects can be obtained even in the case of such a configuration.

[5. Other Embodiments] The present invention is not limited to the above-mentioned respective embodiments, and various other forms can be implemented. For example, the bending angle of the obtuse angle bending portion of the in-phase shunt can be freely set. The material of the in-phase shunt can be freely selected. Further, the specific configuration of the intermediate support portion for supporting the in-phase shunt can be freely designed. Furthermore, in each of the above-described embodiments, the case where the pressure-balancing type expansion bellows is used as the bellows has been described, but the present invention is similar to the gas-insulated bus bar using various bellows for thermal expansion absorption. Is applicable to.

[0037]

As described above, according to the present invention, the cross-sectional shape of the in-phase shunt that connects the vessels on both sides of the bellows and allows the sheath current to flow is a trapezoidal shape having obtuse angle bends at both ends. By doing so, the load generated in the in-phase shunt due to the displacement due to the thermal expansion and contraction of the container can be shared by both the obtuse-angled bent portions at both ends and the parallel portion therebetween. Therefore, it is possible to provide a small-sized gas-insulated busbar that can absorb a predetermined amount of thermal expansion and contraction, has a simple shunt shape, and is highly economical.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a gas-insulated bus bar according to the present invention, in which (A) is a front view and (B) is a side view.
(C) is a plan view.

FIG. 2 is a load vector diagram of the shunt mounting portion in FIG.

FIG. 3 is a plan view showing a second embodiment of a gas-insulated bus bar according to the present invention.

4A is a detailed view of a portion A of FIG. 3, and FIG. 4B is a front view of FIG.

FIG. 5 is a plan view showing a third embodiment of the gas insulated bus bar according to the present invention.

6A is a detailed view of a portion A of FIG. 5, and FIG. 6B is a front view of FIG.

FIG. 7 is a diagram showing a fourth embodiment of a gas insulated bus bar according to the present invention, (A) is a front view and (B) is a side view.

8 is a diagram showing a modification of the gas-insulated bus bar of FIG. 7,
(A) is a front view, (B) is a side view.

9A and 9B are views showing a conventional example of a gas-insulated bus bar having a bellows, in which FIG. 9A is a front view, FIG. 9B is a side view, and FIG. 9C is a plan view.

FIG. 10 is a load vector diagram of the shunt mounting portion of FIG.

[Explanation of symbols]

 1: Gas-insulated busbars 2, 2a, 2b: Container 3: Bellows 3a: Flange 3b: Flange tightening stud 4a, 4b: Shunt seat 5: In-phase shunt 5a, 5b: Right angle bent portion 5c: Parallel portion 5d: U-shaped Bent part 6: Insulation ring 7: Snow cover 10: In-phase shunt 10a, 10b: Obtuse angle bent part 10c: Parallel part 20: Intermediate support part 21: Supporting member 22: Insulation washer 23: Nut 24: Spring gutter 25: Flat gutter 26: Bolt 27: Nut 28: Spring blade 29: Flat blade 31: Long hole 32: Spherical washer

Front Page Continuation (72) Inventor Shinichi Sudo 2-1, Ukishimacho, Kawasaki-ku, Kawasaki-shi, Kanagawa Toshiba Toshiba Substation Equipment Technology Co., Ltd.

Claims (6)

[Claims] 1. A sheath current in which a conductor is housed in a container in which an insulating gas is sealed and which is provided in a part of the container to absorb thermal expansion and contraction, and containers on both sides of the bellows are connected to each other. A gas-insulated bus bar having an in-phase shunt for flowing a gas, wherein the cross-sectional shape of the in-phase shunt is a trapezoidal shape having obtuse angle bends at both ends thereof. 2. An in-phase shunt is supported on the bellows between a part of a parallel part parallel to the bellows in a central part of the in-phase shunt and a part of a central part of the bellows facing the parallel part. The gas-insulated bus bar according to claim 1, wherein an intermediate support portion is provided, and the intermediate support portion includes an insulating member that electrically insulates between the sheath of the bellows and the in-phase shunt. 3. The intermediate support portion is a support member attached to the bellows to support the in-phase shunt, and an elongated hole provided in the parallel portion of the in-phase shunt so as to extend in the axial direction. A bolt that is provided so as to pass through the elongated hole of the in-phase shunt and radially supports the in-phase shunt so that the in-phase shunt can move in the axial direction with respect to the support member. The gas-insulated bus bar according to claim 2, which is characterized in that. 4. The gas-insulated bus bar according to claim 3, wherein a support seat surface of the bolt of the intermediate support portion has a spherical shape. 5. The gas insulation according to claim 3, wherein a washer for supporting the in-phase shunt is attached to the bolt of the intermediate support portion, and a support seat surface of the washer has a spherical shape. Busbar. 6. The gas-insulated bus bar according to claim 1, wherein the in-phase shunt is arranged in a lower portion of the bellows.