JPS62189903A - Gas insulated equipment - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Objective of the Invention 1 (Field of Industrial Application) The present invention relates to insulated equipment, and in particular, to the prevention of metal foreign matter (especially wire metal , @) in order to prevent a drop in withstand voltage by providing a capture means.

(Prior Art) Generally, a load switching device has an insulating slag (generally SF6 scum) sealed inside a case, and is provided with a fixed boar contact and a movable contact. The SF6 gas sealed in the case is normally stable, but it decomposes when exposed to high-temperature arcs when the load current is switched on and off. When this heat is removed, if there is no substance in the atmosphere that can bond with the dispersed acid, it will recombine and return to the original SF6 gas. However, if the metal evaporates, the components of the decomposition gas and metal oxides combine to form metal fluoride powder. This powder increases with the number of times the current is switched on and off, and is deposited on the surfaces of the grounding case, insulating spacer, etc.

In addition, there is a possibility that metal foreign objects may be mixed in when assembling the load switching device. If these metal foreign objects are inside the switchgear, it will cause a drop in withstand voltage.

On the other hand, since the load current does not switch or close on the busbar, metal foreign objects are not generated during operation. However, since pressure is applied during busbar assembly on-site, there is a possibility that metal foreign matter may be mixed in during assembly, leading to a drop in withstand voltage, as in the case of load switching devices.

Hereinafter, these problems will be explained in detail with reference to the drawings.

FIG. 4 shows a gas circuit breaker, which is one of the conventional switching devices for gas insulated equipment.

A fixed side electrode 2 and a movable side electrode 3 are facing each other in a cylindrical ground case 1 which is arranged almost horizontally and filled with an insulating gas such as SF6 gas, and the movable side electrode 3 has a buffer ¥4 inside it. The opening/closing machine leap 7 in the operating machine 6 is connected by the insulating rod 5.
Drive or transmission from.

The fixed electrode 2 and the movable electrode 3 are insulated from the ground case 1 by an insulating tube 8. The high pressure shield 9 is
It is installed to alleviate the electric field of the buffer to 4. When used as a single gas circuit breaker, insulating spacer 1
A bushing can be installed on the 0.

FIG. 5 shows the busbar of a conventional gas insulated device. A high-voltage conductor 11 is disposed in a coaxial cylinder within the grounding case 1, and the high-voltage conductor 11 is supported by an insulating support 12 while being insulated from the grounding case 1. The high voltage conductor 11 is connected with a contact 13 in the middle. The high voltage shield 9 is attached to reduce the electric field at the contactor 13 portion.

In the insulated equipment shown in FIGS. 4 and 5, the high voltage shield 9 has a diameter larger than the high voltage part of the current carrying part.

FIG. 6 is a diagram illustrating the movement of the foreign metal object 14 when the foreign object 14 is present near the high voltage shield 9. As shown in FIG.

As can be seen from FIG. 6, the metal foreign object 14 moves around in the space between the high voltage shield 9 and the ground case 1 due to the combined force F of the electrostatic force FL and the gravity FCI. First of all, metal foreign objects 14 outside the installation range of the high voltage shield 9 receive a force within the installation range of the high voltage shield 9, so all metal foreign objects near the high voltage shield 9 are placed between the high voltage shield 9 and the grounding case 1. Metal foreign matter 14 is collected in the space and moves up and down in that space, and once it enters the installation range of the high voltage shield 9, it does not go out of the installation range of the high voltage shield 9. Among the metal foreign substances 14, this tendency is particularly remarkable for linear metals.

If the metallic foreign matter is in a floating state in this way, the withstand voltage performance of the gap will be significantly reduced. Therefore, if overvoltage, such as a surge, enters the insulated equipment operating in this state, there is a risk of dielectric breakdown. In order to suppress such low withstand voltage performance, it is conceivable to increase the distance between the charging part and the grounded tank 1, but in this case, the grounded tank 1 becomes larger. Furthermore, in circuit breakers and the like, there is a problem in that as current interruptions are repeated, the amount of metal foreign matter 14 generated from the contacts 13 increases, and the life of the contacts 13 is shortened.

(Problems to be Solved by the Invention) As mentioned above, in conventional gas-insulated equipment, metal foreign matter collects and floats between the high-voltage shield and the grounding case, resulting in a decrease in withstand voltage performance between the high-voltage shield and the grounding case. There was a problem of storage.

The present invention was proposed to solve the above-mentioned drawbacks of the conventional technology, and its purpose is to remove metal foreign matter generated or mixed into gas-insulated equipment between the high-voltage shield and the ground case. It is an object of the present invention to provide gas insulated equipment with improved withstand voltage performance by capturing the gas in a position where there is no problem in terms of insulation without causing it to float.

[Configuration 1 of the Invention (Means for Solving the Problems) The gas insulated equipment of the present invention includes a pocket for capturing metal foreign matter that protrudes to the outside in a part of the grounding case facing the high voltage shield, and It is characterized by having an auxiliary electrode or pole for mitigating the electric field.

(Function) By virtue of the present invention having the above-described configuration, foreign metal objects that are once collected in the installation range of the high-voltage shield fall into the pocket and are captured. In this case, the electric field is low within the pocket, and the electric field is alleviated by providing an auxiliary electric current (snow), so the metallic foreign object is hardly moved and does not float again.Therefore, the high-pressure seal) Collected in the space between ~ and the grounding case! = Gold, almost all of the intestines and stomach substances are captured in the bulge 1, and this state is maintained, so the withstand voltage can be improved.

(Example) An actual example of the gas insulated equipment according to the present invention as described above will be specifically described with reference to the drawings. Note that the same parts as those of the conventional example shown in FIGS. 4 to 6 are designated by the same reference numerals, and the explanation thereof will be omitted.

First of all, Figure 1 is a cross-sectional view of the cass breaker, and Figure 2 is a cross-sectional view of the bus bar. There are 15 cylindrical pockets I for capturing metal foreign objects. A snack 16 is provided at the bottom of each of the pockets 15 for capturing metal foreign matter.

FIG. 3 is an enlarged cross-sectional view showing the vicinity of the pocket 15 for capturing metal foreign objects shown in FIGS. An auxiliary electrode 17 consisting of a portion 17b is also provided. The inclined portion 17b of the auxiliary electrode 17 is curved so as to swell toward the same side as the high-voltage conductor, covers the space between the pocket 15 and the cylindrical portion 17a, and protrudes inside the cylindrical portion to extend the diameter of the cylindrical portion 17a. It forms a smaller diameter capture opening.

The operation of this embodiment having the above configuration is as follows.

u [J, money collected in high pressure shield 9, foreign matter 1
4 receives a downward force at the curvature of the entrance of the pocket 15 for capturing metal foreign matter, falls into the pocket, and is collected on the lid 16. In this case, the metal foreign object trapping pocket 15 is captured by a low electric field, and the electric field is further relaxed by the auxiliary electrode 17, so that the metal foreign object 14 hardly moves and does not float again. Therefore, gold and foreign objects 14 can be effectively captured and retained in the pocket 15, thereby improving the withstand voltage, and even if overvoltage such as a surge enters, it still has the initial dielectric strength and will not cause dielectric breakdown. Never. In general, according to this embodiment, there is no need to increase the distance between the grounding tank 1 and the live parts, so it can contribute to the miniaturization of gas insulation equipment. can improve the lifespan of

In particular, in this embodiment, since the curvature of the pockets 1 to 15 in the inclined portion 17b of the auxiliary electrode 17 is reduced, a higher electric field relaxation effect can be obtained. In addition, if metal foreign object 1
Even if the metal foreign object 4 floats up, the tip of the inclined portion 17b of the auxiliary electrode 17 protrudes into the cylindrical portion 17a, which prevents the metal foreign object 14 from flying out from the pocket 15.

[Effects of the Invention] As explained above, according to the present invention, metal foreign matter mixed in before operation and gold and debris generated during operation are collected between the high-pressure shield and the grounded tank. Rear capture pou 1
Since it can be collected in ~ and maintained in this state, it is possible to provide a cass insulation device with the same withstanding voltage performance.

[Brief explanation of drawings]

-〇- Figures 1 and 2 are cross-sectional views of a gas circuit breaker and a bus bar, respectively, which are an embodiment of the gas insulation device according to the present invention.
The figure is a sectional view showing the main part of the embodiment shown in Figs. 1 and 2, Figs. 4 and 5 are sectional views showing the gas circuit breaker and bus bar of conventional gas insulation equipment, respectively, and Fig. 6 is a sectional view of the conventional FIG. 3 is a cross-sectional view showing the movement of metal foreign matter inside the cass insulation device. DESCRIPTION OF SYMBOLS 1... Grounding case, 2... Fixed side electrode, 3... Movable side electrode, 4... Buffer to, 5... Insulating rod,
6... Operating device, 7... Opening/closing mechanism, 8... Insulating cylinder,
9...High voltage shield,]O...Insulating space→ノ,1
1... High voltage conductor, 12... Insulating support, 13...
Contactor, 14... Metal foreign object, 15... Capture pocket, 16... Lid, 17... Auxiliary electrode, 17a...
Cylindrical part of auxiliary electrode, 17b... Inclined part of auxiliary electrode. = 10- Figure 6 □One □

Claims (2)

[Claims] (1) A gas consisting of a high-voltage conductor placed in a cylindrical grounding case placed almost horizontally and filled with an insulating gas such as SF_6 gas, and a high-voltage shield placed coaxially around the high-voltage conductor. Gas insulated equipment, characterized in that a pocket for trapping metal foreign matter protruding to the outside is provided in a part of the grounding case facing the high voltage shield, and an auxiliary electrode for mitigating the electric field is provided in this pocket. . (2) A cylindrical pocket is used as a pocket for capturing metal foreign matter, and a cylindrical part is provided coaxially with the pocket as an auxiliary electrode for electric field relaxation, and a cylindrical part is provided on the high voltage conductor side of this cylindrical part on the same side. An auxiliary electrode is used, which has a bulging curve, covers the space between the pocket and the cylindrical part, and has a sloped part that protrudes inside the cylindrical part to form a capture port with a smaller diameter than the diameter of the cylindrical part. A gas insulated device according to claim 1, which is a gas insulated device.