JPH08294209A - Gas insulated switchgear - Google Patents

Abstract

PURPOSE: To provide a gas insulated switchgear in which a current transformer can be incorporated easily in a vessel in which a circuit breaker is housed. CONSTITUTION: A current transformer conductor 19 is connected to the lower terminal 12 of a circuit breaker CB which is housed in a vessel 1 through a lower conductor 18. A plurality of current transformers CT which detect currents in the current transformer conductors of respective phases are attached to current transformer support frames 32 which are provided for the respectively phases and a current transformer assembly unit 33 is composed of the current transformer support frame 32 and the current transformer CT of each phase Openings if1 which are provided on the bottom plate 1f of the vessel 1 in order to attach enclosing terminal plates 28 which have terminal metal fittings 31 to which the secondary terminals of the current transformers CT are connected are so formed as to have dimensions large enough to insert the current transformer assembly units 33. The current transformer assembly units 33 of the respective phases are inserted into the vessel 1 through the openings 1f1 and fixed to the vessel 1.

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, and in particular, in each part of the gas-insulated switchgear, a circuit breaker and a current transformer for detecting a current of a circuit connected to the circuit breaker are provided in a common container. The present invention relates to an improvement of a portion having a configuration housed in.

[0002]

2. Description of the Related Art A gas-insulated switchgear is a circuit breaker, a disconnector, which is necessary for forming a switchgear circuit in an electric station such as a substation.
When various components such as a grounding switch and current transformer are housed in a container filled with an insulating gas such as SF ₆ gas, and the components are stored separately in multiple containers , The plurality of containers are connected in a gas-divided state via an insulating spacer. FIG. 5 shows an example of the gas-insulated switchgear, in which the equipment housed in each container is shown in a single wire connection diagram.

First, the structure of the container of this gas insulated switchgear will be explained. In FIG. 5, reference numeral 1 is a container for a circuit breaker supported on a rectangular parallelepiped operation device box 2 which also serves as a frame. The container 1 includes a cylindrical portion 1a arranged with its axis oriented in the vertical direction, and first and second cylindrical portions 1a provided so as to project from the upper and lower sides of the side surface of the cylindrical portion 1a to the same horizontal direction, respectively. Branch pipe parts 1b and 1c, and cylindrical part 1
A first and second branch pipe portions 1b and 1c, and third and fourth branch pipe portions 1d and 1e provided so as to project to the opposite side from the upper and lower portions of the side surface of A, respectively. The lower end and the upper end of the portion 1a are respectively a bottom plate 1f and a lid plate 1g.
It has been closed by.

The first to fourth branch pipe portions (also referred to as pipe base portions) 1b to 1d are well-known ones which are short pipes welded to the periphery of holes provided in the peripheral wall portion of the cylindrical portion. A flange is provided at the outer end of each branch pipe portion. The first and second branch pipe portions 1b and 1c are branch pipe portions for connecting bus lines,
First and second busbar containers 2 and 3 are connected to the branch pipe portions 1b and 1c via insulating spacers S1 and S2, respectively. The third branch pipe portion 1d is a device storage container connecting branch pipe portion that connects a container that stores a predetermined device that constitutes a circuit connected to the circuit breaker, and in this example, the cable head container 4 is connected. . The fourth branch pipe portion 1e of the circuit breaker storage container 1 is used as a handhole and is normally closed by the lid plate 5.

The cable head container 4 is a cylindrical container supported on a pedestal 6, and has an upper branch pipe portion 4a and a lower branch pipe portion 4b projecting on opposite sides from each other at the upper and lower portions of the side surface thereof. The upper branch pipe portion 4a is connected to the third branch pipe portion 1d of the circuit breaker housing container 1 via the insulating spacer S3. The lower branch pipe portion 4b of the cable head container 4 is connected to the disconnector container 7 through an insulating spacer S4.
And a surge arrester container 8 is connected to the lower end of the disconnector container 7 via an insulating spacer S5.

In the circuit breaker storage container 1, there is a three-phase circuit breaker C.
B, a three-phase current transformer CT, a current transformer conductor (primary conductor) on which the current transformer is mounted, and circuit breaker inspection ground switches ES11 and ES12 are housed. The arrangement of devices in the circuit breaker container 1 is as shown in FIG. The circuit breaker CB is
The breaker is housed in a cylindrical container 10 whose axis is oriented in the vertical direction, and upper terminals (terminals connected to fixed contacts) are respectively provided at the upper end and the lower end of the circuit breaker CB. ) 11 and a lower terminal (terminal connected to the movable contactor) 12. Circuit breaker CB for each phase
Is arranged with its axis oriented in the vertical direction and is supported on the bottom plate 1f of the container 1 via a support base 13. The movable contactor that constitutes the blocking portion is arranged in the operator box 2. It is connected to an operating device (not shown) via an insulating operating rod. One end of a first busbar-side upper conductor 14 extending in the horizontal direction is connected to the upper terminal 11 of the circuit breaker CB of each phase, and the other end of the conductor 14 of each phase is connected via a second busbar-side upper conductor 15. It is connected to the through conductor of each phase of the insulating spacer S1.
The upper ends of the upper and lower connecting conductors 16 are connected to the other end of the first busbar-side upper conductor 14 of each phase, and the lower end of the connecting conductor 16 of each phase is connected to each phase of the insulating spacer S2 through the busbar-side lower conductor 17. Connected to the through conductor. Further, a first circuit breaker checking ground switch ES11 is provided between the lower end of the upper and lower connecting conductors 16 of each phase and the ground potential portion.

One end of a line-side lower conductor 18 extending in the horizontal direction is connected to the lower terminal 12 of the circuit breaker CB of each phase,
The other end of the lower conductor 18 is connected to the lower end of a current transformer conductor 19 which is arranged with its axis parallel to the circuit breaker CB. The upper end of the current transformer conductor 19 of each phase is the line-side upper conductor 20.
, And the other end of the upper conductor 20 of each phase is connected to the penetrating conductor of each phase of the insulating spacer S3. A second circuit breaker inspection ground switch ES12 is provided between the line-side upper conductor 20 and the ground potential portion. A plurality of (five in the illustrated example) current transformers CT are attached to the current transformer conductor 19 of each phase in a state of being stacked in the axial direction.

The first busbar BUS is provided in the first busbar container 2.
The three-phase conductors forming 1 and the three-phase first busbar side disconnectors DS11 are housed, and the conductors of each phase forming the first busbar BUS1 are the first busbar-side disconnector DS11 and the insulating spacer. S
It is connected to the line-side upper conductor 15 connected to the upper terminal of the circuit breaker CB through the through conductor of each phase of 1. In addition, the second busbar BUS2 is formed in the second busbar container 3
The phase conductor and the second busbar-side disconnector DS12 are housed,
The conductors of each phase forming the second busbar BUS2 are connected to the line-side lower conductor 17 connected to the upper terminal of the circuit breaker CB through the second busbar-side disconnector DS12 and the through conductor of each phase of the insulating spacer S2. There is.

In the cable head container 4, the line-side disconnector DS2, the cable head CHD, and the line-side grounding switch E
S2 and 3 phases are stored. Line side disconnector D for each phase
One end of S2 is connected to the through conductor of each phase of the insulating spacer S3, and the other end is connected to the terminal of the cable head CHD. A line side grounding switch ES2 is provided between the terminal of the cable head and the ground.

A disconnector D for connecting a lightning arrester is provided in the disconnector container 7.
S3 is stored for 3 phases. One end of the disconnector DS3 of each phase is connected to the terminal of the cable head CHD in the cable head container 4 through the through conductor of each phase of the insulating spacer S4 and a predetermined connecting conductor, and the other end of the disconnector DS3 of each phase is connected. The end is connected to the through conductor of each phase of the insulating spacer S5.

A three-phase lightning arrester LA is housed in the lightning arrester container 8, and the non-grounded terminal of the lightning arrester LA of each phase is connected to the other end of the disconnector DS3 through the through conductor of each phase of the insulating spacer S5. .

In the conventional gas-insulated switchgear of this type, the three-phase current transformer was assembled as shown in FIGS. 7 and 8 and housed in the container 1 as shown in FIG. Figure 7
In addition, in FIG. 8, in order to distinguish the U, V, and W3 phase constituent parts, the suffixes u, v, and w are added to the reference numerals indicating the U, V, and W3 phase constituent parts, respectively.

In FIGS. 7 and 8, 21 and 23 are an upper holding plate and a lower holding plate, respectively, and 22 is an upper holding plate 2.
Intermediate presser plate arranged between 1 and lower presser plate 23, 2
4u to 24w are cylindrical shields, CTu to
CTw is a current transformer formed by winding a secondary coil around an annular iron core, 25u to 25w are spacers formed in an annular shape, 26
Is a total screw stud bolt (a bolt provided with a screw over the entire length).

In this example, each of the holding plates 21 to 23 is provided with three holes for fitting the shields 24u to 24w, and between the holding plates 21 and 22 and between the holding plates 22 and 23. A predetermined number of three-phase current transformers CTu to CTw, which are laminated in a predetermined number respectively, are arranged so as to be aligned with the holes provided in the respective holding plates. Spacers 25u to 25w are inserted between the stacked current transformers, and three holes provided in each of the pressing plates 21 to 23 and a predetermined number of current transformers CTu to be stacked between these pressing plates. Shield 24 through the inner circumference of CTw
u to 24w are provided. Shield 24u ~ 24w
The flanges provided at the upper ends of the
, And a nut screwed to these stud bolts, and a plurality of stud bolts 26, 26, ...
1 to 23 are fastened and the three-phase current transformer is integrated.

The current transformer assembly 27 assembled as described above is housed in the container 1 from above and mounted on the current transformer conductor 19, and at least a part of the holding plate, for example, the lower holding plate. 23 is bolted to a fixing member welded to the inner surface of the container 1.

In the illustrated example, three current transformers of each phase are stacked between the upper pressing plate 21 and the intermediate pressing plate 22.
Two current transformers of each phase are stacked and arranged between the intermediate presser plate 22 and the lower presser plate 23.
Illustration of the current transformer arranged between the upper pressing plate 21 and the intermediate pressing plate 22 is omitted.

In the above gas insulated switchgear, the container 1
When assembling the device inside, the current transformer assembly 27 is lifted by a crane, and the lid 1g and the bottom plate 1f are removed from the container 1
Inside, the current transformer assembly 27 is hung and fixed to the container 1. The upper conductor 20 is connected to the through conductor of the insulating spacer S3, and the ground switch ES12 is attached to the upper conductor 20.

On the other hand, a circuit breaker CB is attached to the bottom plate 1f, and a lower conductor 18 and a current transformer conductor 19 are attached to the lower terminal 12 of the circuit breaker CB. In this state, the container 1 is lifted up to combine the cylindrical portion 1a and the bottom plate 1f, and the three-phase current transformer conductor 19 serves as the shield 24u of the current transformer assembly 27.
The upper end of the current transformer conductor 19 of each phase is connected to the upper conductor 20 of each phase with the inside of ~ 24w being penetrated. Further, a ground switch ES12 is attached to the upper conductor 20. The secondary terminal of the current transformer of each phase is connected to a predetermined terminal fitting of a sealed terminal plate 28 attached so as to close a hole formed in the bottom plate 1f of the container 1 via a lead wire. Further, the upper conductor 15 is connected to the upper terminal 11 of the circuit breaker CB via the bus-side upper conductor 14.
After mounting the upper and lower connecting conductors 16 and the lower conductors 17, SF ₆ gas is sealed in the container 1 at a predetermined pressure and the assembling work is completed.

[0019]

In the gas-insulated switchgear described above, when it is necessary to add or replace the current transformer, the gas in the container 1 for accommodating the circuit breaker is recovered, and then the cover plate 1 is removed.
g, and the grounding switch ES12 and the upper conductor 20 are removed. Further, the cover plate 5 is removed from the branch pipe portion 1e forming the handhole, and the current transformer conductor 19 is removed by performing work through the inside of the branch pipe portion. In this way, after securing a space above the current transformer assembly 27, the current transformer assembly 27 is lifted by a crane and removed from the container 1.

After adding and replacing the current transformer to assemble a new current transformer assembly 27, the assembly is incorporated into the container 1, the current transformer conductor 19 is connected, and then the upper conductor 20 is connected. And attach the grounding switch ES12. At this time, ground switch E
Re-adjustment work for the fixed contact side and the movable contact side of S12 is required. Then attach the lid plate 1g,
Gas is sealed in the container 1.

As described above, in the conventional gas-insulated switchgear, it is necessary to remove the upper conductor 20 and the grounding switch ES12 when the current transformer is incorporated in the breaker housing container 1. However, there is a problem that the number of assembling steps increases.

In addition, when adding a current transformer to the existing gas-insulated switchgear or replacing the current transformer, it is necessary to reassemble the grounding switch ES12. At that time, the grounding switch ES12 must be reassembled. However, there is a problem in that the time required for the assembling work becomes long because the centering adjusting work of the above is required.

Further, in the conventional gas insulated switchgear,
Since the three-phase current transformers have been integrated into the container all at once, there is also a problem that a heavy machine such as a crane is required.

In addition, in the conventional gas-insulated switchgear, it is necessary to remove the cover plate 1g of the container 1 when adding or replacing the current transformer, so that when the gas-insulated switchgear is installed outdoors, The work was troublesome because consideration was required to prevent the infiltration of rainwater into the container 1.

An object of the present invention is to provide a gas-insulated switchgear which solves the above-mentioned problems by allowing the current transformer to be installed and removed through a handhole provided in the bottom plate of the circuit breaker housing container. To provide.

[0026]

According to the present invention, there is provided a container having a cylindrical portion arranged with its axis oriented in the vertical direction, and the lower end and the upper end of the cylindrical portion are closed by a bottom plate and a lid plate, respectively, and an upper end. For the three-phase circuit breaker and the lower terminal of the three-phase circuit breaker, which have a lower terminal and an upper terminal in the portion near the bottom and the portion near the lower end, respectively, and are housed in the container with their axes oriented vertically. A three-phase lower conductor whose one end is connected to each other, and a three-phase current transformer which is arranged with its axis lines parallel to the three-phase circuit breaker and whose lower end is connected to the other end of the three-phase lower conductor. A conductor, a sealed terminal plate attached so as to hermetically close an opening provided in the bottom plate of the container, and a grounding for grounding the three-phase current transformer conductor at the upper end side of the three-phase current transformer conductor. A current transformer that includes a switch and detects the current flowing through the current transformer conductor of each phase. At least one is provided, the secondary terminals of the current transformer are those related to the gas insulated switchgear which is connected to the terminal fittings provided in the sealed terminal plate.

In the present invention, the current transformer of each phase is collectively attached to the current transformer support frame provided for each phase to form a current transformer assembly, and the current transformer set of each phase is formed. Support the solid against the container. The opening provided in the bottom plate of the container is formed in such a size that the current transformer assembly of each phase can be inserted therein.

The current transformer support frame is arranged, for example, in parallel with the support member having a cylindrical portion surrounding the current transformer conductor and a flange formed at one end of the cylindrical portion, and in parallel with the flange of the support member. At least one holding plate,
The holding plate and the flange of the support member can be configured by through bolts. In this case, the current transformer is fitted in the outer periphery of the cylindrical portion of the support member and is attached in a state of being sandwiched between the holding plate and the flange of the support member. Further, in this case, a fixing plate is attached to the inner surface of the container, and the flange of the supporting member of the current transformer supporting frame is fixed to the fixing plate.

[0029]

As described above, by collectively mounting the current transformers of each phase on the current transformer support frame provided for each phase,
When the current transformer assembly is configured for each phase, the current transformer assembly for each phase can be configured sufficiently smaller than the assembly in which the current transformers for three phases are collectively incorporated. It can be inserted into the container through an opening provided in the bottom plate of the container for attaching a sealed terminal plate connecting the secondary terminals of the sink. Therefore, it is possible to attach and detach the current transformer of each phase without removing the lid plate on the upper part of the container and without removing the grounding switch arranged on the upper part of the container. There is no need to disassemble or reassemble the grounding switch when replacing or replacing. Therefore, the work for adding or replacing the current transformer can be simplified, and the work time can be shortened.

Further, since a heavy machine such as a crane is not required to handle the current transformer assembly of each phase, the equipment required when adding or replacing the current transformer can be simplified.

Further, with the above construction, it is not necessary to remove the cover plate of the container when adding or replacing the current transformer, so that when the gas insulated switchgear is installed outdoors,
Since it is not necessary to consider to prevent rainwater from entering the container 1, the work can be facilitated.

[0032]

FIG. 1 shows an essential part of an embodiment of the present invention. In this embodiment, points other than the current transformer mounting structure are the same as those shown in FIGS. 1 in FIG.
Is a container for accommodating a circuit breaker similar to that shown in FIG. 5, and this container 1 comprises a cylindrical portion 1a with its axis oriented in the vertical direction, and a branch pipe portion provided so as to project from the side surface of the cylindrical portion. 1b
.About.1e (only the branch pipe portion 1e is shown in FIG. 1). The opening at the lower end and the opening at the upper end of the container 1 are closed by a bottom plate 1f and a lid plate 1g (not shown in FIG. 1), respectively, and a three-phase cutoff is provided on the bottom plate 1f via a mount 13. The vessel CB is supported. One end of the lower conductor 18 is connected to the lower terminal of the circuit breaker CB of each phase,
The other end of the lower conductor 18 is connected to the lower end of a current transformer conductor 19 which is arranged with the axis line parallel to the circuit breaker CB. In this embodiment, a circular opening 1f1 is provided in the bottom plate 1f, located directly below the current transformer conductor 19 of each phase, and a sealed terminal plate 28 is attached so as to close the opening 1f1. . In the illustrated example, an adapter flange 30 is fixed to the sealed terminal plate 28, and the adapter flange 30 is hermetically connected to the peripheral portion of the opening 1f1. A large number of terminal fittings 31 to which the secondary terminals of the current transformers of each phase are connected are attached to the sealed terminal plate 28.

In this embodiment, the opening 1f1 is used when the current transformer assembly is inserted into the container. Therefore, the opening 1f1 is formed in such a size that the current transformer assembly described later can be inserted therein.

The current transformers CT of the respective phases mounted on the current transformer conductors 19 are collectively attached to the current transformer support frame 32 provided for the respective phases so as to form the current transformers CT of the respective phases. A current transformer assembly 33 is configured by the current transformer support frame 32. More specifically, the current transformer support frame 32
Is a support member 34 (FIG. 2A) integrally including a cylindrical portion 34a surrounding the current transformer conductor 19 and a flange 34b formed at one end of the cylindrical portion, and a first holding plate 35 (FIG. 2B).
The second holding plate 36 (FIG. 2C), and the holding plates 35 and 3
6 and the flange 34b of the supporting member, and through bolts 37 for fastening each other.

The first pressing plate 35 has an annular plate-shaped portion 35a having the same contour shape as the flange 34b of the support member 34 and arranged in parallel with the flange 34b, and the plate-shaped portion 35a.
And a semi-cylindrical shield wall 35b provided so as to extend in the axial direction from the outer peripheral portion of the plate-shaped portion 35a, the inner peripheral portion of the plate-shaped portion 35a is brought into contact with the upper end of the cylindrical portion 34a of the support member 34, The lower end of the shield wall 35b is placed in contact with the outer peripheral portion of the flange 34b of the support member 34. The second pressing plate 36 is an annular plate having the same contour shape as the flange 34b of the support member 34, and is fitted to the outer periphery of the cylindrical portion 34a of the support member 34. In this embodiment, two current transformers CT are fitted to the cylindrical portion 34a of the support member, and these current transformers are connected to the flange 34 of the support member.
It is arranged between b and the second holding plate 36.

Supporting member 34 is formed with holes 35c and 36c penetrating through the portions of the first pressing plate 35 near the outer circumference and the portions of the plate-like portion 36a of the second pressing plate 36 near the outer circumference, respectively. A screw hole 34c is formed by penetrating a portion of the flange 34b near the outer periphery of the flange 34b so as to be aligned with the holes 35c and 36c. Through bolts 37 penetrating holes 35c and 36c provided in the first and second pressing plates 35 and 36, respectively, are screwed into screw holes 34c of the flange of the support member 34. In addition, a nut 38 is screwed into the through bolt 37 at a desired position, so that the through bolt 37 and the nut 3
, 38, ... fasten the first and second pressing plates 35 and 36 to the flange portion 34a of the support member 34,
Due to this fastening, an appropriate tightening force is applied to the current transformers CT arranged in layers.

A fixing plate 39 for fixing the flange 34b of the support member of the current transformer support frame 32 is welded to the inner surface of the container 1 for accommodating the circuit breaker, and the flange 34 of the support member 34 is welded.
The lower end of the through bolt 37 protruding downward from b is provided in a state of penetrating a hole provided in the fixed plate 39.
Then, the nut 40 is screwed into the end of the through bolt 37 penetrating the hole of the fixed plate 39, and the support member 34 is fastened to the fixed plate 39 by tightening the nut 40, so that the current transformer assembly 33 is stored in the container. Supported against 1.

The flange 34b of the support member 34 is fixed to the fixing plate 3
In order to facilitate the contact between the flange 34b and the fixed plate 39 when fastening to 9, the outer peripheral portion of the flange 34b of the support member 34, the outer peripheral portion of the plate-like portion 35a of the holding plate 35 and the outer periphery of the holding plate 36. Cutouts 34d, 35d, and 36d each having a size capable of penetrating the fixing plate 39 are formed in the respective portions.

In this embodiment, the support member 34 is provided to shield the current transformer CT from the current transformer conductor 19,
The shield wall 35b is provided to shield the current transformer CT from the charging part of the circuit breaker CB. Other points are shown in Figure 5.
And the conventional gas insulated switchgear shown in FIG.

In this embodiment, when the current transformer assembly 33 is incorporated into the container 1, the adapter flange 30 is removed and the opening 1f1 is opened to connect to the lower end of the current transformer conductor 19. Remove the lower conductor 18. In this state, the separately assembled current transformer assembly 33 is inserted into the container 1 through the opening 1f1, and the cutouts 34d, 35d and 36d are aligned with the fixing plate 39, and the current transformer is assembled. The transformer assembly is inserted into the container along the current transformer conductor 19 so that the inside of the cylindrical portion 34a of the support member 34 is inside the current transformer conductor 1.
9 should be penetrated. Flange 34 of support member 34
When the cutout portion 34d of b reaches a position above the fixed plate 39, the current transformer assembly 33 is rotated to fit the lower end of the through bolt 37 into the hole of the fixed plate 39, and the flange 34b. Is brought into contact with the upper surface of the fixing plate 39, a nut 40 is screwed onto the lower end of the through bolt 37, and the nut is tightened.

After that, the lower conductor 18 is attached to each current transformer C.
The secondary terminal of T is connected to the terminal fitting 31 of the sealed terminal plate 28 via a lead wire (not shown). After that, the sealed terminal board 28
The adapter flange 30 to which is attached is connected to the peripheral portion of the opening 1f1, and the assembling of the current transformer is completed.

As described above, when the current transformers of the respective phases are collectively attached to the current transformer support frame provided for the respective phases, the current transformer assemblies are constructed for the respective phases. Since the phase current transformer assembly can be configured sufficiently smaller than the current transformer assembly in which the current transformers for three phases are collectively incorporated,
It can be inserted into the container through an opening provided in the bottom plate of the container for attaching a sealed terminal plate for connecting the secondary terminal of the current transformer. Therefore, the current transformer of each phase can be attached / detached without removing the lid plate on the upper part of the container and without removing the grounding switch ES12 arranged on the upper part of the container. There is no need to disassemble or reassemble the grounding switch when replacing or replacing. Therefore, it is possible to simplify the work when adding or replacing the current transformer,
Working time can be shortened.

If the current transformer assembly is constructed for each phase as described above, a heavy machine such as a crane is not required to handle the current transformer assembly for each phase, and therefore a current transformer is added or The equipment required for replacement can be simplified.

Further, as described above, if the current transformer assembly is configured to be inserted into the container through the opening provided in the bottom plate of the container, the lid plate of the container is added when the current transformer is added or replaced. Since there is no need to remove it, it is not necessary to take precautions to prevent rainwater from entering the container 1 when the gas insulated switchgear is installed outdoors, and the work can be facilitated.

FIGS. 3 and 4 show a modified example of the current transformer assembly used in the present invention. In this example, the first holding plate 35 is an annular plate similar to the second holding plate 36. The shield wall is omitted from the first pressing plate 35. In this example, the second pressing plate 36 and the flange 34b of the support member
The two current transformers CT are stacked between the first pressing plate 35 and the second pressing plate 36, and the current transformer CT is further arranged between the first pressing plate 35 and the second pressing plate 36. Further, in this example, the outer peripheral portion of the flange 34b of the support member 34, the first and second pressing plates 35 and 36.
Projecting pieces 3 projecting radially outward from the outer peripheral portion of the
4e, 35e and 36e are provided. The projecting pieces 35e and 36e provided on the first and second pressing plates 35 and 36 are provided with holes for penetrating the through bolts 37, and the projecting piece 34e provided on the flange 34b of the support member 34 is provided on the projecting piece 34e. A screw hole for screwing the through bolt 37 is formed. Other points are the same as those of the embodiment shown in FIGS. 33u in FIGS.
.About.33w show three-phase current transformer assemblies of U to W phases, respectively.

In the above embodiment, the current transformer support frame 3
2, the support member 34 and the first and second pressing plates 35 and 3
However, when the number of current transformers provided in each phase is small, the second holding plate can be omitted.

FIGS. 5 and 6 show an example of the structure of the gas-insulated switchgear to which the present invention is directed. The structure of the container connected to the circuit breaker storage container and the structure of the container housed in each container. The device to be used is not necessarily limited to the illustrated example.

[0048]

As described above, according to the present invention, the current transformer of each phase is collectively attached to the current transformer support frame provided for each phase, and the current transformer assembly for each phase is provided. Since the current transformer assembly is inserted into the container through the opening provided in the bottom plate of the container for attaching the sealed terminal plate for connecting the secondary terminal of the current transformer, the upper part of the container It is possible to attach and detach the current transformer of each phase without removing the lid plate of the and without removing the grounding switch placed on the upper part of the container, and when adding or replacing the current transformer. There is no need to disassemble or reassemble the ground switch. Therefore, the work for adding or replacing the current transformer can be simplified and the work time can be shortened.

Further, according to the present invention, since the current transformer assembly is constructed for each phase, a heavy machine such as a crane is not required to handle the current transformer assembly of each phase, and a current transformer is added. It is possible to simplify the equipment required when performing the replacement.

Further, according to the present invention, since the current transformer assembly is inserted into the container through the opening provided in the bottom plate of the container, the lid of the container is added when the current transformer is added or replaced. No need to remove the board. Therefore, when the gas-insulated switchgear is installed outdoors, it is not necessary to take care to prevent rainwater from entering the container, and the work can be facilitated.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 2A is a plan view of a support member that constitutes a current transformer support frame used in an embodiment of the present invention, FIG. 2B is a bottom view of a first holding plate that constitutes the support frame, and FIG. 8B] is a plan view of a second holding plate that constitutes the same support frame. [FIG.

FIG. 3 is a configuration diagram showing a configuration of a main part of another embodiment of the present invention.

FIG. 4 is a perspective view showing a main part of the embodiment shown in FIG.

FIG. 5 is a configuration diagram showing an example of the configuration of a gas-insulated switchgear to which the present invention is directed.

6 is a cross-sectional view showing the arrangement of devices in a circuit breaker storage container of the gas insulated switchgear of FIG.

FIG. 7 is an exploded perspective view of a current transformer assembly used in a conventional gas insulated switchgear.

FIG. 8 is a perspective view of a conventional current transformer assembly.

9 is a perspective view schematically showing a state in which the current transformer assembly of FIG. 8 is housed in a container.

[Explanation of reference numerals] 1 breaker housing container 1a cylindrical portion 1b to 1e branch pipe portion 1f bottom plate 1f1 opening 1g lid plate 18 line-side lower conductor 19 current transformer conductor 20 line-side upper conductor 28 sealed terminal plate 30 adapter flange 32 Current Transformer Support Frame 33 Current Transformer Assembly 34 Support Member 35 First Holding Plate 36 Second Holding Plate 37 Through Bolt 38, 40 Nut 39 Fixing Plate CT Current Transformer CB Circuit Breaker ES11, ES12 Circuit Breaker Inspection Grounding switch

Claims (2)

[Claims] 1. A container having a cylindrical portion arranged with its axis oriented in the vertical direction, the lower end and the upper end of the cylindrical portion being closed by a bottom plate and a lid plate, respectively, and a portion near the upper end and a portion near the lower end. 3 each of which has a lower terminal and an upper terminal and is housed in the container with the axis line oriented vertically.
A three-phase circuit breaker, a three-phase lower conductor whose one end is connected to a lower terminal of the three-phase circuit breaker, and three-phase circuit breakers arranged with their axes parallel to each other. A three-phase current transformer conductor whose lower end is connected to the other end of the lower conductor, a sealed terminal plate attached so as to hermetically close the opening provided in the bottom plate of the container, and the three-phase transformer. A grounding switch for grounding the three-phase current transformer conductors on the upper end side of the current transformer conductor, and at least one current transformer for detecting a current flowing through the current transformer conductor for each phase is provided; In the gas-insulated switchgear in which the secondary terminal of the current transformer is connected to the terminal provided on the sealed terminal plate, the current transformers of each phase are grouped together on the current transformer support frame provided for each phase. Attached to each phase and composed of a current transformer of each phase and a current transformer support frame A gas-insulated switchgear in which a solid body is supported with respect to the container, and an opening provided in a bottom plate of the container has a size capable of inserting the current transformer assembly of each phase. . 2. The current transformer support frame is arranged side by side in parallel with a support member having a cylindrical portion surrounding the current transformer conductor and a flange formed at one end of the cylindrical portion, and a flange of the support member. At least one pressure plate,
A through bolt for mutually fastening the holding plate and the flange of the support member, wherein the current transformer is fitted to the outer periphery of the cylindrical portion of the support member and is provided between the holding plate and the flange of the support member. The gas-insulated switchgear according to claim 1, wherein the gas-insulated switchgear is mounted in a sandwiched state, and a fixing plate that fixes a flange of a support member of the current transformer support frame is attached to an inner surface of the container.