JPH09200916A - Gas insulated switch device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide weight reduction in a 3-phase integral GIS by improving a cable terminal tank. SOLUTION: Tanks for fitting a cable terminal part are made into branched tanks 51 to 53 of phase separated structure which is independent for each phase. The branched tanks 51 to 53 are fitted onto GIS tank 3 so that their axial direction may be disposed horizontally. A cable terminal part CHd is constituted of an L type cable terminal and fitted on the atmospheric side of the branched tanks 51 to 53. It is possible to eliminate a tank for sealing the cable terminal part CHd with the cable terminal part CHd three-phase-integrated, by using the L type cable terminal usable on the atmospheric side, providing reduction in the size and weight of GIS.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a power plant, a substation,
The present invention relates to a gas-insulated switchgear (hereinafter referred to as "GIS") for electric power used in switchyards and power receiving stations,
In particular, the present invention relates to a three-phase integrated GIS in which the components for three phases are stored in one tank.

[0002]

2. Description of the Related Art FIG. 6 is a sectional view showing one unit of a conventional three-phase collective GIS. GIS10 is a circuit breaker tank 1,
It is composed of a busbar tank 2, a lightning arrester tank 3, a cable terminal tank 4, and a front operation box 7. Each tank has
The components for three phases are stored together. Also in the cable terminal tank 4, the in-gas cable terminal portions CHd for three phases are arranged in one tank. The power cable 31 connected to the cable terminal CHd outside the tank
Is drawn to the outside through the current transformer CT housed in the frame 6 supporting the cable terminal tank 4.

The respective constituent devices of the GIS of FIG. 6 are connected as shown in the single line connection diagram of FIG. The details will be described later.

[0004]

There has been a demand for reducing the size and weight of the GIS. An object of the present invention is to reduce the weight of a three-phase GIS by improving the cable terminal tank.

[0005]

In order to achieve the above object, the present invention provides a tank for cable end portion mounting in a three-phase batch type GIS with an independent phase separation type tank for each phase. This cable end mounting tank is
It is attached to the GIS tank so that its axial direction is arranged horizontally. The cable terminal portion for connecting to the power cable is composed of an L-shaped cable terminal and is attached to the atmosphere side of the cable terminal portion mounting tank.

The above-mentioned L-shaped cable terminal is GI on the atmosphere side.
It is possible to disconnect the connection with S or to apply voltage for cable test. Therefore, according to the present invention, the cable end tank for sealing the cable end portion in the insulating gas can be omitted. Further, the cable terminal tank and the pedestal supporting the tank can be downsized.
As a result, the GIS can be made smaller and lighter.

[0007]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows one unit of a three-phase collective GIS in a cross section, and FIG. 2 shows a plan view taken along the line AA of FIG. The three-phase collective type GIS10 includes a circuit breaker CB, grounding switches ES-1 and ES-2, a line side disconnecting switch DS-L, and a circuit breaker tank 1 in which a line side grounding switch ES-L is housed, a bus BUS. , A busbar tank 2 that houses the busbar-side disconnector DS-B, a lightning arrester tank 3 that houses the lightning arrester LA, and a front operation box 7 that houses the operating mechanism of the circuit breaker CB.

In the lightning arrester tank 3, the cable end portion CHd
Three branch tanks 51, 52, 53 for mounting
Is attached. The axial direction of each branch tank is arranged horizontally. Of the three branch tanks, the intermediate-phase branch tank 52 has a shape linearly extending from the lightning arrester tank 3. The other two-phase branch tanks 51 and 53 arranged on both sides thereof are formed so as to extend from the lightning arrester tank 3 in a right-angled direction, and are then bent at a right angle to be aligned in parallel with the intermediate-phase branch tank 52. .

An L-shaped cable terminal is used as the cable terminal portion CHd. Details of the L-shaped cable terminal will be described later. This cable terminal portion CHd is attached to the atmosphere side of the branch tanks 51 to 53 of each phase,
The conductors 1 to 53 are connected to the lightning arrester LA and the like. Further, the power cable 31 is connected to the cable terminal portion CHd and led out to the outside through the current transformer CT. The current transformer CT is supported by the mounting bracket 8.

As shown in FIG. 2, the cable terminal CHd
The mounting positions on the plane of are alternately staggered. That is, the distance B from the reference position of the arrester tank 3 to the cable end portion CHd of the central phase is set to be larger than the distance C to the cable end portion CHd of both phases. This configuration is adopted when the diameter of the current transformer CT to be used is large and it is difficult to arrange the current transformer CT on a straight line.
When the diameter of the current transformer CT is small or when the distance between the branch tanks 51 to 53 can be set large, the attachment position of the cable terminal portion CHd can be arranged in a straight line on the plane.

The connection of the GIS of FIGS. 1 and 2 will be described with reference to FIG. The busbar BUS in the busbar tank 2 is connected to the busbar side terminal of the circuit breaker CB in the circuit breaker tank 1 through the busbar side disconnector DS-B. The line side terminal of the circuit breaker CB is connected to the cable terminal CH through the line arrester tank 3 and the branch tanks 51 to 53 via the line side disconnector DS-L.
connected with d. The power cable 31 connected to the cable terminal portion CHd is guided to the outside through the current transformer CT.

Grounding switches ES-1 and ES-2 are respectively connected to the busbar side and the line side of the circuit breaker CB, and the line side grounding switch ES-L and the lightning arrester LA are connected to the line side of the line side disconnector DS-L. Are connected. The detailed structure of the cable terminal portion CHd is shown in FIG. The cable terminal portion CHd has a bushing 11 made of epoxy resin. The bushing 11 is horizontally provided with a first inner conductor 12 for connecting to a conductor in the lightning arrester tank 3. Also, power cable 3
A second inner conductor 13 for connecting to 1 is provided in the vertical direction.

The first inner conductor 12 and the second inner conductor 13
And are connected by a connection conductor 16. The connection conductor 16 is removable, and the lid 21 and the premolded insulator 19 are removed to perform connection or removal work. The bushing 11 is attached to the arrester tank 3 by the attachment flange 14 and the attachment ring 15. The tank is hermetically sealed by an O-ring 28 provided between the mounting flange 14 and the tank 3.

The power cable 31 is inserted from below the bushing 11 and is provided at the tip of the cable terminal 2.
2 is brought into contact with a contact 17 attached to the second inner conductor 13. The protective fitting 26 of the power cable 31 utilizes the intermediate flange 24 to make the bushing 1
It is attached to 1. The cable terminal portion CHd of FIG. 4 described above shows a state during normal operation of the GIS 10. FIG. 5 shows a state when the DC withstand voltage is applied to the power cable 31.

When the power cable 31 is tested, the lid 21, the premolded insulator 19 and the connecting conductor 16 are removed in order to apply a DC withstand voltage. Then, the disconnection insulating plug 32 is inserted between the first inner conductor 12 and the second inner conductor 13, and the pressure resistant lead cable 33 is inserted.
Are connected to the second inner conductor 13. This allows
At the time of DC withstand voltage, the DC test voltage is applied to the power cable 31 through the path of the withstand voltage lead cable 33-second inner conductor 13-power cable 31.

Since the L-shaped cable end described above can be used in the atmosphere and does not need to be placed in the insulating gas, the cable end tank for sealing the three phases together with the insulating gas, which is conventionally required, is omitted. be able to. And GIS
Branch tank 5 for connecting L-shaped cable end to 10
Since 1 to 53 can be phase-separated tanks that store only conductors, the size can be reduced. Further, even when a mount for fixing the branch tanks 51 to 53 is installed, the mount may be small. Therefore, the GIS can be reduced in size and weight.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a GIS of the present invention.

FIG. 2 is a plan view seen from the line AA in FIG.

FIG. 3 is a single wire connection diagram in the present invention and the conventional GIS.

4 is a side sectional view showing an example of a cable terminal portion used in the GIS of FIG.

FIG. 5 is a side sectional view showing a different usage state of the cable end portion of FIG.

FIG. 6 is a side sectional view of a conventional three-phase package type GIS.

[Explanation of symbols]

 1 ... Circuit breaker tank 2 ... Bus bar tank 3 ... Lightning arrester tank 4 ... Cable end tank 7 ... Front operation box 8 ... Mounting bracket 10 ... GIS 31 ... Power cable 51-53 ... Branch tank CHd ... Cable end part CT ... Current change vessel

Claims (2)

[Claims] 1. A three-phase batch type gas-insulated switchgear,
The cable terminal installation tank has an independent phase separation type structure for each phase, and is installed in the tank of the gas insulated switchgear with its axial direction arranged horizontally to connect to the power cable. Is an L-shaped cable end, and the L-shaped cable end is attached to the atmosphere side of the tank for attaching the cable end portion. 2. The cable end portion mounting tank for each phase is arranged such that the axial portions of the cable end portion mounting portions are arranged in parallel, and the three-phase cable end portion mounting positions are arranged on a plane. The gas-insulated switchgear according to claim 1, wherein the gas-insulated switchgear is arranged in a staggered manner.