JPS58119189A - Arrester - 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 The present invention is directed to modifying the mounting structure of a lightning arrester housed in a grounding tank.

Generally, the current from the overhead wire is introduced into the train's power circuit through the pantograph. The source circuit passes the current from the pantograph through the vacuum breaker, transformer, and drive motor in that order. By opening and closing the vacuum breaker, the current flowing through the power circuit can be controlled. Therefore, if an accident occurs in the overhead line and a fault current flows, the fault current can be cut off by vacuuming the line and opening the interrupter.

In addition, abnormal voltages caused by lightning or chartering caused by pantographs are absorbed by lightning arresters installed on the grounding wire that branches between the vacuum breaker and the transformer to prevent damage from spreading to other electrical machines. ing.

By the way, since vacuum breakers and lightning arresters installed on trains are air-insulated, they have the disadvantage of increasing their overall volume. Therefore, the inventors thought that if the vacuum breaker and lightning arrester were housed in a grounded tank containing an insulating gas, for example 8Fm gas, the dielectric strength would be improved by the insulating gas, and this would have the advantage of reducing the overall volume. .

However, if the lightning arrester cannot absorb the abnormal voltage, an accident such as a flash fault inside the arrester may occur, causing a ground fault within the arrester, and the arc continues continuously. As the arc continues, the pressure in the grounded tank increases,
Finally, there was a threat that the butterfly ground tank would explode. If it exploded, it could not only damage other equipment but also cause personal injury. Further, even if the grounded tank did not explode, SF'@ decomposed gas was generated in the grounded tank, which corroded the ceramic cylinder of the vacuum breaker and caused a vacuum leak.

On the other hand, when inspecting the inside of the lightning arrester,
Inspection was extremely difficult because the lightning arrester had to be removed and inspected with the F-gas exhausted.

An object of the present invention is to provide a lightning arrester that is safe and easy to replace without causing any adverse effects on other equipment.

In the lightning arrester of the present invention, a lightning arrester element is housed in a sealed container attached to a grounding port, and a pressure relief valve is provided at a terminal with one end of the lightning arrester element and the sealed container closed.

Therefore, if an internal flash fault occurs in the lightning arrester element due to an abnormal voltage and the internal pressure increases in the closed container, the pressure relief valve opens and removes the internal pressure, so that the earthing device can be safely used without being damaged.

Hereinafter, an embodiment of the present invention will be explained using a composite high voltage device 1 as shown in FIG. 1.2.

Insulated gas for two people, for example SF-gas-filled grounded tank 2,
A support insulator 3 and a removable inspection lid 2B are installed between the central inner walls to make the inside airtight. An operation box 4 is attached to the outer surface of the grounded tank corresponding to the support insulator 3. A metal bracket 4 is attached to the other end of the support insulator 3, and at least a pair of fixed contacts 5 are installed inside the metal bracket 4 on the left and right sides.
A vacuum container 7.8 in which a movable contactor 6 and a movable contactor 6 are arranged is attached. Therefore, the insulated operating rod of the operating mechanism section (not shown) housed in the operating box 4 passes through the support insulator 3, extends to the metal bracket 4, and communicates with the movable contact 6 via the link (not shown). are doing. Therefore, when the insulating operating rod is moved, the movable contact 6 approaches and separates from the fixed contact 5.

The vacuum vessel 7 on the right side is connected to a power supply side cable pend 10 via a lead wire 9. Power supply - cable head 10
Although not shown, it is connected to the power bus. The left vacuum vessel 8 is connected to a load side cable head 13 via a lead wire 12. Although the load side cable head 13 is not shown, it is connected to the secondary side of the transformer. These power supply side cable head 10 and load side cable head 13 are attached to a protruding pipe 14 extending in the direction 1 across the ground tank 2.

Details of the lightning arrester 15 disposed in the ground tank on the left side of the load side cable head 13 will be explained with reference to FIG. An airtight container 18 is attached to a protruding pipe 17 which protrudes from the lower side of the grounded tank 2 and has seven flange 16 at the barbed end. The airtight container 1B has 7 flange portions 20A, 2 at both ends of the insulating cylinder 19.
0B is formed, and the l end side 7 tsunge part 20A is the tsunge 2
1 to the high voltage side terminal 22 to close one end of the insulating tube 19. The high voltage side terminal 22 is connected to the lead wire 12. One side of the other end side seven flange portion 20B is in contact with the seven flange 16 via the backing 23. These seven lunges that are in contact with each other are fixed by fixing means (not shown). On the other side of the other end 117 flange portion 20B, a low voltage side terminal 24 is attached, and a pressure relief hole 25 is formed in the low voltage side terminal 24. Since the pressure relief hole 25 is closed by a pressure relief valve 26, the other end of the insulating tube 190 is The front part of the closed container 18 is closed, and the inside of the closed container 18 is airtight.

A surge arrester element 28 in which a plurality of non-linear resistance elements 27 are stacked is housed in the airtight container, and the surge arrester element 28 is compressed by a spring 29 interposed between one end of the surge arrester element 28 and the high voltage side terminal 22. is pressed toward the low voltage terminal side. Therefore, an electric circuit is formed between the high voltage side terminal 22, the spring 29, the lightning arrester element 28, and the low voltage side terminal 24. Y indicates the traveling direction of the train (not shown), and H indicates the height direction of the train.

With this configuration, if an internal accident occurs in the arrester element 28, if an internal flash fault occurs and the arc continues, the inside of the sealed container and the grounded shield will be isolated by the sealed container 18. Therefore, the gas and pressure caused by the arc are released to the outside via the pressure relief valve 26. Therefore, the pressure inside the grounded tank remains unchanged and there is no risk of explosion, making it safe. This is because the arc in the sealed container is isolated from two insulating gases, such as SP-gas, in the grounded tank.
No exposure to SF-gas. Therefore, the Sr gas does not generate decomposition gas, does not attack the safety tube constituting the vacuum container 7.8, and does not cause vacuum leakage.

In addition, if the fixing means 30 provided between the other end side 7 lanre part and the low voltage side terminal 24 is removed, for example, the screw, the lightning arrester element 2 can be removed.
8 can be taken out to the outside. The installation is also the same as described above. In this way, the lightning arrester element 28 can be installed and removed without requiring two people to exhaust and fill in the insulating gas, making the installation and removal work easier.
%, when conducting a withstand voltage test on the composite high voltage equipment 1, it was impossible to do so with the lightning arrester stored and in good condition, and the lightning arrester was removed.However, in the present invention, the lightning arrester can be easily removed. Since it can be installed, withstanding voltage tests can now be easily performed.

Furthermore, in the present invention, the pressure relief valve 26 is provided on the side opposite to the ground tank 2, so there is no risk that the gas and pressure in the closed container will impact the ground tank, and the ground tank will not be damaged. When used in a train, the pressure relief valve 26 faces the V-ru side, so there is no risk of damaging other equipment due to gas pressure, making it safe. Furthermore, if the sealed container 18 containing the lightning arrester element is arranged in the same direction as the load side cable head 13 as shown in Fig. 4, the height dimension H can be made lower than that shown in Fig. 2. is supported on the outside corresponding to the ground tank through hole, so
Workers can install a heavy lightning arrester without having to support it.

As described above, the lightning arrester of the present invention is safe and easy to replace.

[Brief explanation of the drawing]

Fig. 1 is a side cross-sectional view of a composite high-voltage device shown as an embodiment of the present invention, Fig. 2 is a plan view of Fig. 1 viewed from below, and Fig. 3 is - 4 is a side sectional view of a main part shown as another embodiment.

Claims (1)

[Claims] 1. In an insulating gas tank equipped with a lightning arrester, the lightning arrester is installed in a closed container that has an opening at one end and has a high-voltage side terminal, and is housed in the sealed container at the opening. Provided in the lightning arrester element and the lightning arrester element,
A lightning arrester characterized in that it is comprised of a low voltage 1jl14 element that closes an opening, and a pressure relief valve provided at a low voltage side terminal.