JPH02285902A - Gas insulated switch - Google Patents

Abstract

PURPOSE:To conduct the insulation coordination of an electrical equipment even when an arrester is detached by setting insulation performance at the time of the separation of an electrode at a value lower than the ground insulation performance of the electrical equipment and grounding an electrode on the arrester side. CONSTITUTION:A disconnector 15 is composed of a pair of electrodes 15a, 15b, and a distance between the electrodes 15a, 15b at the time of separation is set at a distance where insulation performance at the time of the separation is lower than the ground-insulation performance of buses 10 12. When the disconnector 15 is operated under the state of turn-ON, the disconnector 15 is opened first when an accident is generated in an arrester 14. A grounding cable 17 is connected to the electrode 15b of the disconnector 15, and the disconnector 15 is brought to an open state. A gas gap is formed between the bus 10 and a ground between both electrodes 15a, 15b of the disconnector 15. The insulation performance of the gas gap is set at a value lower than the ground-insulation performance of an electrical equipment, and insulation coordination is performed. Accordingly, the electrical equipment can be protected from an abnormal surge.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a gas-insulated switchgear in which electrical equipment is housed in a grounded container filled with insulating gas.

[Conventional technology]

FIG. 5 is a block diagram of a conventional gas insulated switchgear disclosed in, for example, Japanese Unexamined Patent Publication No. 62-60408, in which a disconnector is provided. In the figure, (1) is a bushing having a conductor (la), which is connected to an aerial power transmission line (2).

(3) - (3) are grounded containers filled with insulating gas, (6
) to (8) are insulating spacers for gas division of each grounding container (3) to (5), and (9) is a pair of electrodes (sa) (sb).
The electrode (9a) is connected to the conductor (la). aQ-(2) is each grounded container (3) to (5)
The bus bar (to) is removably connected to the grounding container (3) via the insulating spacer (6), and the lightning arrester (141) is located inside the grounding container, with one end connected to the grounding container (3). It is connected to the electrode (9b) and the other end is grounded.

Next, the operation will be explained. In the figure, in a normal operating state, the disconnector (9) is in a closed state between the picture electrodes (sa) and (9b). Therefore, even if an abnormal surge intrudes from the power transmission line (2), it is protected by the lightning arrester (14), and insulation coordination between the busbars (10-4, etc.) is ensured.

If it becomes necessary to disconnect the lightning arrester α◆ due to an accident or the like, the disconnector a◆ is opened.

[Problem to be solved by the invention]

Since the conventional gas insulated switchgear is configured as described above, there is a problem in that when the disconnection is opened and the lightning arrester is disconnected, electrical equipment such as the bus bar cannot be protected against abnormal surges.

The present invention was made to solve the above-mentioned problems, and provides a gas-insulated switchgear that can coordinate the insulation of electrical equipment even when the lightning arrester is disconnected.

[Means to solve the problem]

In the gas insulated switchgear according to the present invention, the insulation performance of the pair of tC poles constituting the isolation means of the lightning arrester is set to be lower than the ground insulation performance of the electric equipment when the pair of tC electrodes are separated, and the electrode on the lightning arrester side is grounded. It is designed so that it can be grounded by other means.

[Function] In the gas-insulated switchgear of the present invention, when the lightning arrester is disconnected, the grounded disconnection means is disconnected, so the gap between the two electrodes of the disconnection mechanism acts to protect electrical equipment from abnormal surges. Protect.

[Embodiments of the invention]

An embodiment of the present invention will be described below.

In FIG. 1, (1) to (8) and 4 to G4J are the same as the conventional one. (to) is a disconnector consisting of a pair of electrodes Qsa) Qsb), and when separated, the electrodes (15a) (15b)
The distance between the busbars should be lower than the ground insulation performance of the busbars (b).

FIG. 2 is a configuration diagram showing a state in which the lightning arrester is separated.

In the figure, QlG is a grounding container connected after removing the grounding container Q4 and lightning arrester α◆ in FIG. 1, and aη is a grounding wire placed in the grounding container αQ, which grounds the electrode (1sb).

Next, the effect will be explained. In Figure 1, Shinroki (
If an accident occurs in the lightning arrester Q4 while the surge arrester Q4 is operating in the closed state, first open the disconnector Q4. Then, connect the grounding wire (17) to the disconnector OR as shown in Figure 2.
The disconnector (g) is kept open. As a result, both electric currents of the disconnector (G) are 1!
ii (15a) (A gas gap will be formed between the bus line a1 and the ground between 150 and 150. In this case, the bus mar
# ~ When the insulation performance characteristic of carbon dioxide is characteristic I in Figure 3, the insulation performance of the gas gap is characteristic 1 as characteristic l in Figure 3.
By setting it lower, insulation coordination can be maintained.

In the above embodiment, the bushing (1) is attached to the aerial power transmission line (2).
Although the explanation has been given on a case in which the bus QO is connected through a cable head, similar effects can be expected in a case where the bus QO is connected to an underground power transmission line through a cable head (to) as shown in FIG.

Further, in the above embodiment, the grounding container (6) containing the grounding wire Oη is removed from the grounding container (6) containing the lightning arrester a4.
Although we have explained what connects II, a series circuit of a disconnector and a grounding wire may be housed in a separate grounding container from the first cause grounding container (6) and installed together with the grounding container (2). .

Further, in the above embodiment, the disconnection WOW was used to disconnect the lightning arrester α◆, but other types may be used as long as a predetermined distance can be maintained when the arrester α♦ is disconnected.

〔Effect of the invention〕

As described above, according to the present invention, the surge arrester is removed and the grounding wire is connected, and the disconnecting means of the surge arrester acts as a gas gap, so that insulation coordination can be maintained even after the surge arrester is removed.

[Brief explanation of drawings]

FIGS. 1 and 2 are configuration diagrams showing an embodiment of the present invention,
FIG. 3 is an explanatory diagram showing the voltage (V)-time (1) characteristics of the gas gap. FIG. 4 is a block diagram showing another embodiment of the present invention, and FIG. 5 is a block diagram showing a conventional gas insulated switchgear. In the figure, (3) to (5) are grounding containers, (9) is a disconnector (disconnecting means), (9a) and (9b) are electrodes, and a
O~(b) is a bus bar (electrical equipment), and Qη is a grounding wire (grounding means). In each figure, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] (1) An electrical device is housed in a grounded container filled with an insulating gas, and the electrical device and the lightning arrester are connected through a disconnection means consisting of a pair of electrodes having a predetermined distance when disconnected. A gas insulated switchgear, wherein the insulation performance of the pair of electrodes when they are separated is set to be lower than the ground insulation performance of the electrical equipment, and the lightning arrester side of the pair of electrodes can be grounded by a grounding means.