JPS6223206Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a partially gas-insulated switchgear which can be applied to high-voltage switchyards and has the main bus bar etc. of the switchyard insulated with air and other parts gas-insulated.

In recent years, as the demand for electricity has increased, the application of SF gas insulated switchgear has also expanded. However, high voltage, for example, 500KV switching equipment is often installed in outer ring systems in cities, and therefore, rather than insulating all equipment with SF gas to reduce space, the main busbars of switchyards etc. are Insulating the parts and gas insulating the other parts, combining advantages such as comparatively low land cost due to the suburbs, high reliability of gas insulated equipment, and ease of maintenance, making it overall economical. Gas insulated switchgear, ie, composite gas insulated switchgear, has come into use. This device is often used in high-voltage switchyards, and due to its equipment configuration, it is single-phase and connected to the aerial busbar and service line through terminal bushings. These are placed in parallel for each phase, but because of the high voltage, the insulation distance between the terminal bushings of each phase is long, approximately 8 m in the 500KV class.

Figure 1 shows a single connection diagram of a partially insulated switchyard with double busbars. The A bus and the B bus are connected via bus connection switch/disconnect switches DSA and DSB. From the connection point of both disconnectors DSA and DSB, the overall code is 9.
The partially gas insulated switchgear shown within the two-dot chain line is connected to the power transmission line L. Switching device 9
It is composed of a terminal bushing 1, an instrument current transformer 2, a shield breaker 3, a grounding device 4, a grounding device 5 with induced current switching capability, a disconnector 6, a lightning arrester 7, and an instrument transformer 8. However, a conventional partial gas insulated switchgear 9 of this kind constituting a single connection as shown in FIG.
is formed as shown in FIG. That is, a bushing 1 is installed at the top of one end of a horizontal grounded tank type gas shield breaker 3 via a current transformer 2, and a disconnect switch 6 is installed at the other end in the longitudinal direction via an instrument current transformer 2. A bushing 1 supported by a support frame 11 is installed on the disconnector 6. Terminal bushing 1 through which the main circuit current always flows, instrument current transformer 2,
The shield disconnector 3 and the disconnector 6 form a U-shaped circuit. On the other hand, as shown in Figure 2a, the disconnector 6 disconnects the part where the main circuit current does not normally flow, which is an integral structure of the grounding device 5 with induced current switching ability, the voltage transformer 8, and the lightning arrester 7. It is connected in a straight line in the longitudinal direction of the vessel 3. The single-phase partially gas-insulated switchgear 9 constructed in this way is formed as a switchyard as shown in FIG. 3. U _A , V _A , and W _A placed between the steel towers 12 represent each phase of bus A in Fig. 1, and U _B , V _B , and W _B represent each phase of bus B, and bus A (wA) is Switching disconnector for busbar connection
What is shown is supported by a support member 13 and connected to bus bar B (wB) via DSA and DSB. The connection point of the disconnectors DSA, DSB is connected to the partially gas insulated switchgear 9 via the connection bus 14. In such a configuration, the overall length becomes long, and in particular, the parts where the main circuit current does not always flow, that is, the unit parts of the grounding device 5, the voltage transformer 8, and the lightning arrester 7, are separated from the tower by the dimension indicated by the symbol l. The disadvantage is that the pop-up space cannot be used effectively.
On the other hand, the lightning arrester 7 must be replaced as necessary depending on the number of lightning strikes, but if we also take into consideration the operational space during this replacement, the protrusion dimension from the tower becomes even longer, which is a disadvantage that the land cannot be used effectively. There is.

The present invention was developed in view of the above points, and aims to reduce the space in the switchyard, as well as to inspect lightning arresters,
The purpose of this invention is to obtain a partially gas insulated switchgear that can secure space for work such as replacement.

An embodiment of the present invention will be described below with reference to FIG. In the device of the present invention, the U-shaped circuit formed by the parts through which the main circuit current always flows, that is, the terminal bushing 1, the instrument current transformer 2, the grounded tank type gas insulation disconnector 3, and the gas insulation disconnector 6 is the This is the same as the two-figure configuration. Note that 4 is a grounding device. The elements 1, 2, 3, 4, and 6 thus far constitute a gas-insulated equipment unit, and in this configuration, the main circuit current is constantly flowing through the parts, so they are gas-insulated. The difference in the configuration of the present invention is that the part where the main circuit current does not always flow, that is, the integral unit part consisting of the grounding device 5 with induced current switching ability, the voltage transformer 8, and the lightning arrester 7, is installed differently. . Elements 5, 7, and 8 up to this point constitute an air insulation unit,
In this configuration, the main circuit current does not constantly flow, so it is air-insulated. This unit part is arranged parallel to the longitudinal direction of the disconnector 3, and the grounding device 5 of this unit is mounted perpendicularly to the outlet end of the disconnector 6 to the terminal bushing 1 and connected to each other. Therefore, when the switchgear 10 of the present invention is viewed from above, as is clear from FIG. 4a, the parts where the main circuit current always flows and the parts where the main circuit current does not flow are connected in a U-shape.

When the switchgear 10 configured as described above is installed in a switchyard, the distance between the terminal bushings of each phase is sufficiently long, so that the main circuit current always flows in the space between the adjacent phases, as shown in Figure 5a. You can place units that are not available. On the other hand, in the switchgear 10 according to the present invention, all the equipment can be placed within the space of the steel tower 12, reducing the space of the entire switchyard, as shown in FIG. It is possible to provide a partially gas-insulated switchgear that can perform the inspection and replacement work of the lightning arrester 7 and secure space within the steel tower 12.

[Brief explanation of the drawing]

Figure 1 is a single connection diagram of a double busbar type single connection system, Figures 2a and b are a plan view and front view of a partially gas insulated switchgear applied to the conventional double busbar type, and Figure 3 2 is a block diagram of a switchyard using the switchgear of FIG. 2, FIGS. 4a and b are plan and front views showing an embodiment of the partially gas insulated switchgear of the present invention, and FIGS. 5a and b 1 is a plan view and a front view showing the configuration of a switchyard using the switchgear of the present invention. 1...Terminal bushing, 2...Measurement current transformer,
3...Grounded tank type gas shield disconnector, 4...Grounding device, 5...Grounding device with induced current switching ability, 6...
... Gas insulated disconnector, 7 ... Lightning arrester, 8 ... Instrument transformer, 10 ... Partially gas insulated switchgear, 12
...A steel tower.

Claims (1)

[Scope of utility model registration request] A grounded tank type gas insulation disconnector, a gas insulated disconnector connected in series with the insulation disconnector at least one longitudinal end of the insulation disconnector, and a terminal installed on the disconnector. A gas insulated equipment unit consisting of a bushing through which a main circuit current always flows, and at least a grounding device and a lightning arrester, connected to the disconnector, and arranged in a U-shape on a plane with the gas insulated equipment unit. A partially gas-insulated switchgear comprising an air-insulated equipment unit through which no main circuit current flows at all times.