JP2008086141A - Switchgear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve a problem, wherein a height of a switchgear becomes high when equipment constituting the switchgear is arranged superimposing above and below, in order to reduce an installation area of the switchgear. <P>SOLUTION: Among cases superposed on three stages, upper, middle and lower stages, and sealed with insulating gas airtightly, a busbar is fitted to an outside of a backface of a middle-stage case. First and second three-position disconnecting switches are held in the middle-stage case. A first breaker, connected to the busbar through the first three-position disconnecting switch, is held in the upper-stage case. A first insulating bushing is fitted to the backface of the upper-stage case to connect to the first breaker, then a first outside line cable is connected to the first insulating bushing; while a second breaker connected to the busbar through the second three-position disconnecting switch is held in the lower-stage case; and a second insulating bushing is fitted to a backface of the lower-stage case for connecting to the second breaker, then a second outside line cable is connected to the second insulating bushing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a switchgear used in power transmission / distribution and power reception facilities.

  In order to reduce the installation area of the switchgear, devices that constitute the switchgear are arranged so as to overlap each other (see, for example, Patent Document 1).

JP-A-1010305 (paragraphs 0009 to 0017, FIG. 2)

However, in the switchgear of Patent Document 1, the container for storing the equipment is divided into three stages in the height direction, and a bus bar is arranged at the center of the middle container among them, and is cut off vertically with respect to the bus bar. However, there is a problem that the height of the switch gear is increased because the devices are arranged vertically.
In some cases, it is desirable that the switchgear is installed not only in the installation area but also in a low height, and a switchgear that is remarkably higher than the conventional switchgear is not preferable from the viewpoint of the surrounding equipment.

  In the present invention, among the containers in which the insulating gases stacked in the upper, middle, and lower three stages are hermetically sealed, a bus bar is attached to the outer rear side of the middle container, and the first and second three are placed in the middle container. The position disconnector is housed, and the upper container houses the first circuit breaker connected to the bus via the first three-position disconnector, and the first insulating bushing is attached to the back surface of the upper container A first circuit breaker and a first external cable connected to the first insulation bushing, while a second container is connected to the lower container via a second three-position disconnector. The second insulating bushing is attached to the back surface of the lower container and connected to the second circuit breaker, and the second external cable is connected to the second insulating bushing.

  In order to reduce the installation area of the switchgear, the height of the switchgear can be reduced when the devices constituting the switchgear are arranged one above the other.

Embodiment 1 FIG.
1A and 1B are diagrams showing a switchgear according to Embodiment 1 of the present invention, in which FIG. 1A is a schematic sectional side view, and FIG. 1B is a schematic rear view. Containers 10a and 20b filled with an insulating gas such as SF ₆ (sulfur hexafluoride), dry air, nitrogen, carbon dioxide are stacked one above the other. In the middle container 10b, two three-position disconnectors 20 (also referred to as 3P-DS) that are in three states of on, off, and ground are accommodated and fixed to the front base 11b. The two three-position disconnectors 20 are arranged vertically symmetrically with respect to the bus 30 arranged behind the middle container 10b.

Circuit breakers 40 are accommodated in the upper and lower containers 10a, respectively, and are horizontally fixed to the front base 11a. Insulation bushings 50a and 50b are attached to the rear of the upper and lower containers 10a, respectively, and are connected to the external cables 60a and 60b, respectively. The current transformer for instrument 70 penetrates the insulating bushings 50a and 50b, respectively, and the zero-phase current transformer 80 is disposed at the retracting portion of the external cables 60a and 60b, respectively.
The upper container 10a and the lower container 10a are configured by using members having the same structure in order to share parts.

  Since it is necessary to arrange the external cable 60a so as not to interfere with the bus 30 and the external cable 60b, the insulating bushing 50a is made longer than the insulating bushing 50b. The insulation bushing 50b has such a length that the external cable 60b does not protrude behind the bus 30, and the insulation bushing 50a has a length not less than the sum of the length of the insulation bushing 50b and the thickness of the external cable 60b. It is configured to be disposed behind the bus 30 and the external cable 60b. In the configuration of FIG. 1, the length of the insulating bushing 50a is set so that the protrusion at the joint between the insulating bushing 50b and the external cable 60b does not interfere with the external cable 60a.

In addition, although FIG. 1 demonstrated the case where both the outside line cables 60a and 60b were drawn from the downward direction, you may draw both the outside line cables 60a and 60b from the top, and in that case, the insulation bushing 50b is made longer than the insulation bushing 50a. It ’s fine.
Moreover, as shown in FIG. 3, instead of lengthening the insulating bushing 50a, the external cable 60a is drawn from above rather than downward, so that interference between the bus 30 and the external cable 60b can be avoided.

Although the bus bar 30 is not housed in the middle container 10b as in the configuration of the first embodiment, the height of the middle container 10b can be reduced, and as a result, the effect of reducing the height of the switch gear can be obtained. Since the bus bar 30 is made of solid insulation, the space around the bus bar 30 can be reduced, so that the depth of the installation place can be shortened, and there is no need to perform gas treatment in connection work and maintenance work of the bus bar 30. Furthermore, it is obtained.
Further, since the middle container 20b can be reduced in size by providing the bus bar 30 outside the container, the load applied to the container at the time of pressurizing and sealing with an insulating gas such as SF ₆ gas, dry air, nitrogen, carbon dioxide can be reduced. Thereby, there exists an effect that the thickness of each part which comprises a container can be made thin, or a reinforcement member can be reduced.

In the configuration of FIG. 1, in consideration of workability from the back to the connecting portion of the bus 30 and the external cable 60b, the external cable 60a is arranged not to pass behind the connecting portion of the bus 30 and the external cable 60b. Yes.
As the zero-phase current transformer 80, a track-type one is applied as shown in FIG. The external phase cables 80a and 60b are passed through the zero-phase current transformer 80, but when a circular zero-phase current transformer is applied, the external cables 60a and 60b are bundled into three phases and passed through the zero-phase current transformer. However, by applying the track-type zero-phase current transformer 80, the external cables 60a and 60b can be drawn straight, and the configuration shown in FIG. improves.

FIG. 4 is a diagram showing another configuration of the switchgear according to Embodiment 1 of the present invention. Compared to the configuration of FIG. The structure where the transformer 100 was further accommodated is shown.
The two inspection separation devices 90 are fixed to the front base 11a of the upper and lower containers 10a, respectively. The inspection disconnecting device 90 for the upper container 10a connects and disconnects the instrument transformer 100 to the conductor in a state where voltage is applied to the conductor connecting the circuit breaker 40 and the insulating bushing 50a. Similarly, the instrument transformer 100 of the lower container 10b is connected to and disconnected from the conductor connecting the circuit breaker 40 and the insulating bushing 50b by using the inspection disconnecting device 90.

FIG. 5 is a diagram showing still another configuration, in which the circuit breakers 40 housed in the upper and lower containers 10a are removed from the configuration of FIG. In this configuration, the conductor connected to the three-position disconnector 20 in the middle container 10b is directly connected to the insulating bushing 50a and the insulating bushing 50b in the upper and lower containers 10a.
As described above, it is conceivable that the devices housed in each container differ depending on the configuration of the switch gear. However, since the bus bar 30 is connected across a plurality of switch gears, the same position regardless of the configuration of the switch gear. Placed in.

Further, not only a vertically symmetric configuration around the bus bar 30 but also an asymmetrical configuration is conceivable. FIG. 6 shows a configuration in which a three-position disconnector 20 is further accommodated in the upper container 10a with respect to the configuration of FIG. The three-position disconnector 20 of the upper container 10a is fixed to the front base 11a and connected between the circuit breaker 40 and the insulating bushing 50b.
In the configuration of FIG. 6, since there are many devices stored in the upper container 10 c, the shape of the container is changed to a shape that protrudes to the rear. Since the upper container 10c has a shape projecting to the rear, an upper cable 10c having the same length as the insulating bushing 50b connected to the lower container 10b is connected to the outer cable 10c. 60a can be configured not to interfere with the bus 30 and the external cable 60b.

  In general, in order to prioritize the use of a smaller container as a standard, the configuration of FIG. 6 is increased when the number of devices stored in the container is increased based on the container used for the upper container 10a in the configuration of FIG. It is conceivable to use a large container as the upper container 10c. However, if priority is given to the common structure of the upper container, it can be unified with the container 10c used in FIG. 6 instead of the container 10a used in FIG. In this case, it is not necessary to prepare insulating bushings having different lengths, and it is possible to use insulating bushings 50b having the same length.

  FIG. 7 shows a configuration in which the equipment stored in the lower container 10b is changed from the configuration of FIG. In the configuration of FIG. 7, the lower container 10a houses the instrument transformer 100 and the zero-phase voltage detector 110, and is connected to a conductor connected to the three-position disconnector 20 in the middle container 10b. Yes.

It is also conceivable that there is no container in the upper stage or the lower stage. FIG. 8 shows a configuration in which one of the three-position disconnector 20 in the lower container 10c and the middle container 10b is removed from the configuration in FIG. 7, and FIG. 9 shows the upper container 10a and the middle container 10b in the configuration in FIG. This is a configuration excluding one of the three-position disconnectors 20.
In any configuration, since the connection is made to the common bus 30 with the adjacent container, the position of the bus 30 is the same as the configuration from FIGS. 1 to 7.

Alternatively, a composite current transformer 120 in which an instrument current transformer and a track-type zero-phase current transformer are integrally cast as shown in FIG. 10 may be used. 10A is a schematic top view, and FIG. 10B is a schematic side sectional view. The composite current transformer 120 includes a core 122 of an instrument current transformer around a through-hole 121 through which a bushing of each phase passes. The track type zero-phase current transformer core 123 is integrally cast, and has both functions of an instrument current transformer and a zero-phase current transformer.
By using this composite current transformer 120, each phase of the insulation bushings 50a, 60b is passed through the instrument current transformer 70 as in the configuration of FIG. 1, and the external cable 60a, The operation of penetrating 70b is not necessary, and it is only necessary to pass each phase of the insulating bushings 50a, 60b through the through-hole 121 of the composite current transformer 120. The operation of penetrating the flow device 80 is not necessary, and the restrictions on the arrangement of the external cable are reduced, and the workability is further improved.

It is the schematic side sectional view and schematic back view which show the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic top view which shows the structure of a zero phase current transformer. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is a schematic sectional side view which shows the structure of the switchgear of Embodiment 1 of this invention. It is the schematic top view and schematic sectional side view which show the structure of a composite type current transformer.

Explanation of symbols

10a, 10b, 10c Container 20 3-position disconnector 30 Busbar 40 Circuit breaker 50a, 50b Insulating bushing 60a, 60b External cable 70 Current transformer for instrument 80 Zero-phase current transformer 120 Compound current transformer

Claims (8)

A container in which insulating gases stacked in three stages, upper, middle, and lower, are hermetically sealed;
A busbar attached to the back outside of the middle container;
A first circuit breaker connected to the bus bar via a first three-position disconnector housed in the middle container, and housed in the upper container;
A first insulating bushing connected to the first circuit breaker and attached to the back outer side of the upper container;
A first external cable connected to the first insulating bushing;
Connected to the busbar via a second three-position disconnector housed in the middle container, a second circuit breaker housed in the lower container, connected to the second circuit breaker, A second insulating bushing attached to the back outside of the lower container;
A switchgear comprising a second external cable connected to the second insulating bushing.   2. The switchgear according to claim 1, wherein the first external cable and the second external cable are drawn from below, and the first insulating bushing is longer than the second insulating bushing.   2. The switchgear according to claim 1, wherein the first external cable and the second external cable are drawn from above, and the second insulating bushing is longer than the first insulating bushing.   2. The switchgear according to claim 1, wherein the first external line cable is drawn from above and the second external line cable is drawn from below.   2. The switchgear according to claim 1, wherein the bus bar is made of solid insulation.   2. The switchgear according to claim 1, wherein the upper container is projected rearward from the lower container.   2. The switchgear according to claim 1, wherein a track-type zero-phase current transformer is attached to one or both of the first external line cable and the second external line cable.   A combined current transformer in which an instrument current transformer and a track-type zero-phase current transformer are integrally cast is attached to one or both of the first insulating bushing and the second insulating bushing. The switchgear according to claim 1.

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