JPH06113418A - Gas-insulated switchgear - Google Patents

Abstract

PURPOSE:To provide a gas-insulated switchgear wherein it is small-sized, its degree of freedom in a designing operation is large and it is optimum for a UHV system by improving the arrangement and connection constitution of at least two lightning arresters which are situated on the side of the breaker of a conduit-line bus. CONSTITUTION:A gas-insulated switchgear which is provided with a breaker 22, with a line-side bushing 24 and with a bushing-connecting conduit-line bus 15 which connects the breaker 22 to the bushing 24 is installed on the ground on which an open channel K1 has been formed. A conduit-line bus 15 is passed inside the open channel K1, and three lightning arresters 10, 11, 12 are connected to the conduit-line bus 15. Two 10, 11 out of the three lightning arresters 10, 11, 12 are installed in the neighborhood of rise parts 13, 14 where the conduit- line bus 15 comes in and out from the open channel K1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a gas insulated switchgear for a trunk system such as UHV, and more particularly to an improved arrangement of gas insulated electrical equipment.

[0002]

2. Description of the Related Art UHV power transmission improves system stability associated with long-distance large-capacity power transmission, high-power power transmission such as a trunk outer ring system, solves technical problems such as increase in system short-circuit current, and transmits power line routes. As an effective power transmission method that can reduce the number and reduce transmission loss, its development and practical use are being promoted in Japan and other countries. In such a UHV system, as will be described below, the arrangement configuration of the lightning arrester that suppresses the overvoltage generated in the system is an extremely important element for realizing the downsizing of the equipment.

That is, at a high voltage such as UHV, the charging current between the wires and between the wires and the ground surface increases, so that a phenomenon that is relatively insignificant in the system of 550 kV or less becomes apparent and affects the equipment. It will be. For example, in the conventional 275 kV and 500 kV system, one lightning arrester for each phase is installed at the line entrance and the transformer end in order to protect devices such as circuit breakers and transformers from lightning surges.

However, in the 1000 kV system, the layout of the substation equipment becomes large and the distance between the line entrance and the circuit breaker increases. Therefore, 1000k
In the V system, in order to protect the circuit breaker from a lightning surge that enters when the circuit breaker is released, it is necessary to provide two line-side lightning arresters for each phase on the pipeline bus on the line side of the circuit breaker.

Further, for the following reason, there may be a case where it is necessary to install three line-side lightning arresters for each phase on the pipeline bus. That is, the transmission line of the 1000 kV system has a longer distance than that of the lower system because it functions as a means of transporting electric power from a power source in a remote place. For example, in a 550kV system, the maximum length of the transmission line is 100k.
Although it is about m, the maximum is 250 km in the 1000 kV system.
Also reaches. Further, the 1000 kV transmission line has a large conductor configuration in order to reduce corona noise.
For example, in the 500 kV system, a maximum of 6 conductors constitutes one phase conductor, but in the 1000 kV system, 8 conductors constitute 1 phase conductor.
It constitutes a phase conductor for each phase. As a result, 1000 kV
In the system, the charging capacity of the line is significantly larger than that in the 500 kV system.

Therefore, the level of the persistent overvoltage due to load shedding is 1.5 pu in the 500 kV system, while it reaches 1.7 to 1.8 pu in the 1000 kV system. Therefore, the line-side arrester is required to have extremely severe energy duty. For example, 500k
The energy duty, which was 3 MJ for the V system arrester, reaches 100 MJ or more for the 1000 kV system arrester.

In order to withstand such a severe energy duty, it is sufficient to connect the arrester elements in multiple parallels.
There is a manufacturing limit to the number of parallels that can be stored in one lightning arrester.
From this, there arises a case where it is necessary to add a third lightning arrester to the two lightning arresters and to install a total of three line-side lightning arresters in the pipeline bus.

By the way, in such a lightning arrester for a 1000 kV system, four lightning arrester elements are provided per lightning arrester in order to reduce the limiting voltage and increase the duty of switching surge.
It is considered to connect them in parallel. In this case,
The lightning arrester itself becomes large and becomes the same size as or larger than the circuit breaker, and it becomes the largest of the devices constituting the gas insulated switchgear. For this reason, the installation / connection configuration of the lightning arrestor has a great influence on the arrangement / connection configuration of the entire gas-insulated switchgear.

On the other hand, the third lightning arrester is, as described above,
In particular, it is installed for alternating persistent overvoltage. Therefore, unlike a lightning arrester installed against a lightning surge, if it is electrically connected to the line side of the circuit breaker,
The effect can be exerted regardless of the position of the arrangement / connection on any part of the line. In addition, since there are almost no examples in which three lightning arresters are provided in one line as described above, no particular standard regarding the layout design is known at this stage.

That is, the arrangement / connection configuration of the lightning arresters in the case of three lightning arresters has a great influence on the arrangement / connection configuration of the entire gas-insulated switchgear, but has a high degree of freedom in the arrangement design. Therefore, regarding the three arresters, it is desired to realize a layout / connection configuration that is as rational as possible and that is convenient for downsizing the entire gas-insulated switchgear.

FIG. 6 is a plan view showing the arrangement of an example of a conventional gas insulated switchgear used in such a UHV system and in which three arresters of each phase are arranged. In this example, a third lightning arrester is added to a gas-insulated switchgear having two arresters for each phase, which was considered before the analysis of the UHV system proceeded. The gas insulated switchgear of this conventional example is provided on the ground where the open conduit K1 is formed, and the main bus bar 2
0 and the line side bushing 24 are connected.

In this conventional example, two main lines of two phases and three phases of two main lines are used.
0s are arranged close to each other and in parallel. From these main buses 20, transmission line circuits 30A and 30B are drawn out at right angles to the main buses 20 via respective bus-side disconnectors 21, and are connected to one end of a circuit breaker 22. The other end of each breaker 22 is connected to a bushing 24 via a line-side disconnector 23 and a bushing-connecting pipeline bus 15.

Further, a breaker 22 of each of the bus lines 15 is provided.
From the vicinity, a lightning arrester connecting bus bar 17 branches at a right angle, and further, a circuit breaker side lightning arrester 10 is connected to the lightning arrester connecting bus bar 17 at a right angle. On the other hand, the bushing side lightning arrester 11 is connected near the bushing 24 of each pipeline bus 15. Further, the third lightning arrester 12 is further connected to the lightning arrester connection bus 17 branching from each pipe bus 15 in such a manner that it is branched at a right angle.

[0014]

However, the conventional gas-insulated switchgear having the above-mentioned structure has the following problems. That is, in the conventional gas-insulated switchgear, each of the two arresters for each phase is arranged so as to be branched from a single arrester connecting busbar that is branched at a right angle from the pipeline busbar. Therefore, as shown in FIG.
The two arresters connected to each arrester connecting bus bar were arranged in series in the axial direction of the main bus bar, and largely protruded in the axial direction of the main bus bar from the circuit breaker and the conduit bus bar. Such protrusion of the lightning arrester has a great influence on the arrangement of the adjacent wirings, and in particular, as shown in FIG.
When the adjacent lines are drawn out in the same direction as in this conventional example shown in FIG. 3, the distance L between the lines in the axial direction of the main bus line becomes long, and as a result, the gas insulated switchgear becomes large in size. It was happening.

The present invention has been proposed in order to solve the problems of the prior art as described above, and its object is to dispose at least two lightning arresters on the breaker side of the pipeline bus.
An object of the present invention is to provide a gas insulated switchgear which is small in size and has a high degree of freedom in design and which is optimal for a UHV system by improving a connection configuration.

[0016]

In order to achieve the above object, a gas-insulated switchgear of the present invention is provided on the ground where an open conduit is formed, and has a circuit breaker, a line side bushing, the circuit breaker and the bushing. And a bushing connection pipe busbar for connecting with, the pipe busbar passes through the open conduit, a gas insulated switchgear in which a plurality of lightning arresters are connected to the pipe busbar, in the plurality of lightning arresters At least two of the lightning arresters are installed in the vicinity of a rising portion where the pipe busbar goes in and out of the open conduit.

[0017]

In the present invention having the above construction,
At least two lightning arresters of the plurality of lightning arresters can be distributed and arranged in empty spaces on both sides of each rising portion where the pipeline bus goes in and out of the open conduit. Therefore, in the vicinity of the circuit breaker, it is not necessary to arrange the two lightning arresters in series in parallel with the axial direction of the main busbar. Therefore, the arrester does not significantly project in the axial direction of the main busbar, and the lightning arrester It is possible to minimize the influence of the protrusion on the arrangement of adjacent lines. Particularly, according to the present invention, when the adjacent wirings are drawn out in the same direction, the distance between the lines in the axial direction of the main bus bar can be shortened, and the entire gas insulated switchgear can be downsized.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A plurality of embodiments of the present invention will be specifically described below with reference to the drawings. The same members as those in the conventional example shown in FIG. 6 are designated by the same reference numerals, and the description thereof will be omitted.

A. First Embodiment (1) Configuration of the First Embodiment ... FIGS. 1 to 3 This embodiment is a typical embodiment of the gas insulated switchgear of the present invention, and FIG. 1 shows the gas of the present embodiment. FIG. 2 is a plan view showing the arrangement configuration of the insulating switchgear, FIG. 2 is a side view of the same, and FIG.
FIG. 3 is a single-line connection diagram showing an example of a UHV system line circuit corresponding to the same device. The gas-insulated switchgear of this embodiment is
As shown in FIGS. 1 and 2, as in the conventional example, the open channel K
1 is provided on the formed ground. Further, in the present embodiment, as in the above-mentioned conventional example, the main bus 20 having two phases and three phases each.
Are arranged close to each other and parallel to each other. From these main buses 20, transmission line circuits 31A and 31B are drawn out at right angles to the main buses 20 via respective bus-side disconnectors 21, and are connected to one end of a circuit breaker 22. The other end of each breaker 22 is connected to a bushing 24 via a line-side disconnector 23 and a bushing-connecting pipeline bus 15.

In the present embodiment, the pipeline bus 15 passes through the open channel K1 and the road R is above the open channel (FIG. 2). In the vicinity of each circuit breaker 22 of this pipeline bus 15,
The staggering part 13 to the open channel K1 is provided in zigzag (FIG. 1). That is, each pipeline bus 1 of the power transmission line 31A
5, the two external phase start-up parts 13 are connected to the main bus 20
The riser 13 of the inner phase is located equidistant from the starter 13 of the inner phase and is closer to the bushing 24 than the riser 13 of the outer phase. In addition, of each pipeline bus 15 of the power transmission line 31B,
The two-phase start-up section 13 near the power transmission line 31A is located equidistant from the main bus 20 and has the remaining one-phase start-up section 13.
Are closer to the main bus 20 side than the rising portions 13 of these two phases.

A lightning arrester connection bus bar 37 branches off from the upper part of the rising portion 13 (FIG. 2), and this arrester connection bus bar 3
A lightning arrester 10 is connected to 7 (FIG. 1). These lightning arresters 10 are provided in the vicinity of the rising portion 13, specifically, in the empty space on both sides of the open conduit K1 near the main bus 20.

On the other hand, the rising portions 14 to the outside of the open channel K1 are provided in a staggered manner near the bushing 24 in the open channel K1 of the pipeline bus 15. That is, the start-up unit 14 of each pipeline bus 15 of the power transmission line 31A is connected to the power transmission line 31B.
From the side, it is installed so as to approach the main bus 20 side in sequence,
The rising portion 14 of each pipeline bus 15 of the power transmission line 31B is provided symmetrically with this.

A lightning arrester connecting bus bar 38 branches off from the upper part of these rising portions 14 (FIG. 2), and this arrester connecting bus bar 3
A lightning arrester 11 is connected to 8 (FIG. 1). These lightning arresters 11 are provided in the vicinity of the start-up section 14, specifically, in the empty spaces on both sides of the open conduit K1 near the bushing 24.

A lightning arrester 12 is connected to each of the bus lines 15 near the bushing 24.

(2) Operation and effect of the first embodiment As described above, according to the gas insulated switchgear of this embodiment,
Three arresters 10, 11, 1 for each pipeline bus 15
Two of the lightning arresters 10 and 11 out of 2 are arranged parallel to the pipeline bus 15 in the empty space on both sides of the rising portions 13 and 14 where the pipeline bus 15 goes in and out of the open conduit K1. The three lightning arresters 10, 11 do not project in the direction of the adjacent line in series with the axial direction of the main bus 20. Therefore, by reducing the space for installing the lightning arrestor to be secured on the side of the pipeline bus 15, the distance in the axial direction of the main bus 20 between the respective transmission line circuits 31A and 31B drawn in the same direction is shortened. The entire gas-insulated switchgear can be downsized.

In particular, according to this embodiment, the arresters 10, 1
Lightning arrester connection busbars 37, 38 for connecting 1 to the pipeline busbar 15
Are branched from the upper portions of the rising portions 13 and 14, respectively. Therefore, it is not necessary to newly provide the branch portions of the arrester connection buses 37 and 38 on the pipeline bus 15, and the configuration of the entire gas insulated switchgear can be simplified. B. Second Embodiment ... Fig. 4 In the present invention, the lightning arrester arranged in the vicinity of the open conduit can be arranged only on one side of the pipeline bus for each transmission line circuit (second embodiment). That is, FIG. 4 is a plan view showing the arrangement and connection configuration of the vicinity of the open conduit part of the conduit bus line in the second embodiment of the present invention, but in the second embodiment,
The two lightning arresters 10 and 11 of each phase are both pipe busbars 15.
It is arranged only on one side, and the open conduit K2 is formed in a substantially rhombic shape when viewed from above in accordance with the arrangement of the respective rising portions 13 and 14. The second embodiment has an advantage that the flow line of the worker moving at the time of maintenance and inspection is shortened and simplified, and the maintenance and inspection is facilitated.

C. Third Embodiment FIG. 5 In the present invention, each lightning arrester can be arranged with its longitudinal direction horizontal (third embodiment). That is, FIG. 5 is a plan view showing the arrangement and connection configuration of the portion near the bushing in the third embodiment of the present invention. The third embodiment has an advantage that it is excellent in earthquake resistance because the center of gravity of the arrester 12 is lowered.

D. Other Embodiments The present invention is not limited to the above-described embodiments, and specific device configurations and connection / arrangement configurations of respective parts can be appropriately changed. For example, the arrangement of two arresters for each phase in the vicinity of the start-up portion is not limited to that illustrated in the first embodiment or the second embodiment, and each arrester is installed on either side of the pipeline bus. It is up to you to do it. Also, regarding the staggered arrangement of the rising portions of each phase, it is arbitrary which phase of the rising portions is arranged closer to the main bus.

[0029]

As described above, according to the present invention, by improving the arrangement of the arrester, which greatly affects the arrangement of the adjacent wirings, the size is reduced and the degree of freedom in design is increased.
It is possible to provide an optimal gas-insulated switchgear for a UHV system.

[Brief description of drawings]

FIG. 1 is a plan view showing an arrangement configuration of a gas insulated switchgear according to a first embodiment of the present invention.

FIG. 2 is a side view of the device.

FIG. 3 is a single wire connection diagram showing an example of a UHV system line circuit corresponding to the same device.

FIG. 4 is a plan view showing an arrangement / connection configuration of pipeline bus bars in a portion near an open conduit part of one power transmission line circuit according to a second embodiment of the present invention.

FIG. 5 is a plan view showing the arrangement and connection configuration of a portion near a bushing in one power transmission line according to the third embodiment of the present invention.

FIG. 6 is a plan view showing an arrangement configuration of an example of a conventional gas insulated switchgear.

[Explanation of symbols]

 10, 11, 12: Lightning arrester 13, 14: Start-up section 15: Pipe busbar for bushing connection. 17, 18, 37, 38: Lightning arrester connection bus bar 20: Main bus line 21: Bus line side disconnector 22: Circuit breaker 23: Line side disconnector 24: Bushing 30, 31: Transmission line circuit

Claims (1)

[Claims] 1. A breaker, a line-side bushing, and a bushing-connecting pipe busbar connecting the breaker and the bushing, which are provided on the ground where an open conduit is formed, and which connect the circuit breaker and the bushing. In a gas-insulated switchgear in which a plurality of lightning arresters are connected to the pipeline bus via the inside of the open conduit, at least two lightning arresters of the plurality of lightning arresters are arranged so that the pipeline bus goes in and out of the open conduit. A gas-insulated switchgear that is installed near the lifting part.