JPS592362B2 - Lightning arrester - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lightning arrester, particularly to a lightning arrester for a compact substation.

Lightning arresters used in compact substations and the like installed in narrow sites are required to be downsized, and gas-insulated type devices using SF6 gas or the like are usually used.

As shown in Figure 1, lightning arresters that use silicon carbide (SiC) elements as the non-linear characteristic element, which is the main element, have a grounding container 2 concentrically surrounding a bus bar 1, which is the central conductor, and SF6 in the insulation space 3 inside the grounding container 2
A grounding tank 2a also filled with SF6 gas is connected to the grounding container 2 in the middle of the electric line filled with gas, and the lightning arrester element 4 is housed inside this, and it is connected between the bus bar 1 and the grounding tank 2a. It is normal to do so.

This lightning arrester element 4 has a lightning discharge gap 5 and a nonlinear characteristic element 6.
A plurality of these are connected in series and used depending on the bus voltage, that is, the system voltage used.

As a result, when the operating system voltage becomes high, the lightning arrester element 4 becomes large, and the grounding tank 2a needs to be enlarged, which has the drawback that it is difficult to downsize the lightning arrester element 4.

Recently, the silicon carbide element mentioned above has been replaced by zinc oxide type (ZnO) which has the ability to follow and break during discharge and does not require a discharge gap.
With the development of nonlinear characteristic elements, it has become possible to realize lightning arresters that are even more suitable for reduced size.

Figure 2 shows a lightning arrester using this. In this device, a part of the grounding container 2 is enlarged, and a plurality of nonlinear characteristic elements 7 are installed in this part according to the system voltage used. 1 and a grounded container 2.

Note that 8 is an insulating support for supporting the nonlinear characteristic element.

Compared to the above-mentioned one, this type has no discharge gap, so there is no need to provide a grounding tank just by increasing the size of the grounding container 2, which has the advantage of simplifying the structure, but as the system voltage increases, the non-linearity required Since the number of the characteristic characteristic elements 7 increases, the grounding container 2 in this part becomes large, which has the disadvantage that it is difficult to downsize it.

In view of the above-mentioned drawbacks, it is an object of the present invention to provide a compact lightning arrester suitable for downsized substations, etc. by considering the arrangement method of nonlinear characteristic elements.

FIG. 3 shows an embodiment of the present invention. In the figure, 7 is a non-linear characteristic element made of zinc oxide, and 8 is a non-linear characteristic element provided between the bus bar 1 and the grounding vessel 2 to support the non-linear characteristic element γ. The conical insulating support 9 is a connecting line connecting the non-linear characteristic element 7 between the bus bar 1 and the grounding container 2.

FIG. 4 is a sectional view taken in the direction of the arrow from the A-A section in FIG. 2 is connected in series.

With this configuration, even if the system voltage is high and it becomes necessary to connect a large number of nonlinear characteristic elements 7 in series, the grounding container 2 can have a much smaller diameter than the conventional one, and the lightning arrester can be made smaller. can be measured.

FIG. 5 shows another embodiment of the present invention, in which four nonlinear characteristic elements 7 are stacked in one block and connected in series, and are arranged in a spiral shape on an insulating support 8 as in the previous example. This is installed by winding it and connecting it with the connecting wire 9 between the bus bar 1 and the grounding container 2. Even with high system voltages, it can be realized with a smaller grounding container than the previous example, and it also has non-linear characteristics at low voltage. It has the advantage of being able to use elements.

FIG. 6 is a diagram showing still another embodiment, which is applied when the discharge current of the lightning arrester is large. There are queues.

In the figure, the nonlinear characteristic element 7 is replaced by a conical insulating support 8.
Although an example of linear connection is shown above, the nonlinear characteristic element 7 can also be provided on the back surface of the insulating support 8 to further increase the current capacity.

As explained above, according to the present invention, by considering the spatial arrangement of nonlinear characteristic elements, it is possible to downsize a lightning arrester used in a downsized substation or the like.

This brings about advantages such as simplifying the structure of the downsized substation, reducing the site area, and reducing the amount of gas used.

[Brief explanation of the drawing]

Figure 1 is a schematic cross-sectional view of a conventional grounded tank type lightning arrester used in a compact substation, etc., which uses a silicon carbide element as a nonlinear characteristic element, and Figure 2 shows a similar nonlinear characteristic element using a zinc oxide element. Schematic cross-sectional view of what was used, Figure 3.
FIG. 4 is a schematic side sectional view and a sectional front view of one embodiment of a lightning arrester according to the present invention, and FIGS. 5 and 6 are schematic sectional views of a lightning arrester according to other embodiments of the invention. In the figure, 1 is the bus bar, 2 is the grounding container, 3 is the insulation space, and 6
, 7 are nonlinear characteristic elements, and 8 is an insulating support. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A bus bar and a grounding container disposed concentrically surrounding the bus bar, which is wound in a spiral shape in an insulating space within the grounding container, or provided at an angle with respect to the grounding container. and a plurality of nonlinear characteristic elements connected between the bus bar and the grounding container. 2. The lightning arrester according to claim 1, wherein the nonlinear characteristic element is arranged on a conical insulating support provided between the bus bar and the grounding container. 3. The lightning arrester according to claim 1 or 2, wherein a plurality of non-linear elements connected between the bus bar and the grounding container are connected in series and arranged in parallel in multiple rows. Device.