KR200253963Y1 - Outer current transfomer-typed gas insulation switch gear - Google Patents

Abstract

The present invention relates to a current transformer external gas insulated switchgear, the single phase conductor 20 is penetrated in the tank 10 filled with SF6 gas, the cylindrical current transformer cover 30 on one side of the outer peripheral surface of the tank 10 The openable and fixed installation, the current transformer 40 for converting the large current flowing in the single-phase conductor 20 into a small current of the secondary side is fixedly installed in the current transformer cover 30, the current transformer 40 and The insulating ring 34 is provided between the outer circumferential surface of the tank 10 to facilitate the maintenance and inspection of the current transformer and to prevent moisture from penetrating from the outside, thereby eliminating erroneous discharge caused by the discharge gap plate of the current transformer. It is to improve the operation reliability.

Description

Outer current transfomer-typed gas insulation switch gear}

The present invention relates to a current transformer installed in a gas insulated switchgear, and more particularly to a current transformer external gas insulated switchgear provided with a current transformer outside the gas insulated switchgear.

In general, a gas insulated switchgear is a device used to prevent the spread of an electrical accident in the event of a failure of an ultra-high voltage transmission line and to open and close the line when inspecting a device such as a transformer.

As shown in FIG. 1, a conventional gas insulated switchgear is provided with a single phase conductor 120 penetrating into a tank 110 filled with SF6 gas, and a current transformer 140 is installed on an inner wall of the tank 110. In contact with the gas.

The current transformer 140 is a facility for converting a large current flowing from the primary side of the single phase conductor 120 into a small current of the secondary side, and the discharge gap plate 145 provided at both ends of the tab terminal 144 is opened by the current transformer secondary circuit. It protects not only the current transformer 140 itself but also the relay or meter of the current transformer secondary circuit from the overvoltage caused by the overvoltage caused by the overcurrent or the fault current. The secondary terminal of the current transformer 140 is drawn out to the outside to protect the relay or It is connected to the instrument circuit.

As shown in FIG. 2, the conventional current transformer 140 has incomplete airtight processing from the secondary terminal board 141 to the junction box 142 and is easily infiltrated from the outside due to the infiltrated moisture. As the discharge gap plate 145 of the current transformer 140 is erroneously discharged, there are many cases in which the protective relay malfunctions.

In addition, as shown in FIG. 3, the gap between the discharge gap plates 145 provided at both ends of the maximum tap terminal 144 among the tap terminals 144 of the current transformer terminal box 143 may change due to vibration or current transformer inspection. There was a problem that the discharge gap plate 145 is likely to be mis-discharged.

The present invention has been devised to solve the above problems, install a current transformer on the outside of the tank to facilitate maintenance inspection, cover the outside of the current transformer to cover the outside of the current transformer terminal board from the outside The purpose of the present invention is to provide a current transformer external gas insulated switchgear which can improve the operation reliability of the protection relay and reduce the mis-discharge by removing the discharge gap plates installed at both ends of the current tap terminal.

The present invention for achieving the above object, the single-phase conductor is installed in the tank filled with SF6 gas, the cylindrical current transformer cover on the outer circumferential surface of the tank is fixedly installed so that one side is open, the current transformer cover A current transformer for converting a large current flowing in the single-phase conductor into a small current on the secondary side is fixedly installed in the interior thereof, and an insulating ring is installed between the current transformer and the outer circumferential surface of the tank.

Therefore, the current transformer prevents moisture from penetrating into the current transformer terminal board by the cover, thereby reducing malfunction, and making maintenance inspection of the current transformer easy.

1 is a schematic side cross-sectional view showing a gas insulated switchgear according to the prior art;

2 is a schematic front view showing a current transformer terminal board and a junction box of a gas insulated switchgear according to the related art;

3 is a schematic side cross-sectional view showing a current transformer terminal box of a gas insulated switchgear according to the related art;

4 is a schematic side cross-sectional view showing a gas insulated switchgear according to the present invention;

5 is a schematic side cross-sectional view showing a current transformer terminal box of a gas insulated switchgear according to the present invention.

Explanation of symbols on the main parts of the drawings

10 tank 20 single phase conductor

30 cover 31 support plate

32: top plate 33: vertical cover

34: insulation ring 35: fixing bracket

36: fixed stud 40: current transformer

41: current transformer terminal box 42: tap terminal

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Figure 4 is a schematic side cross-sectional view showing a current transformer external gas insulated switchgear according to the present invention, Figure 5 is a schematic side cross-sectional view showing a current transformer terminal box of the current transformer external gas insulated switchgear according to the present invention.

According to the present invention according to the drawings, the single-phase conductor 20 is penetrated in the tank 10 filled with SF6 gas, and one side of the cylindrical current transformer cover 30 is openable on the outer circumferential surface of the tank 10. It is fixedly installed, the current transformer 40 for converting the large current flowing in the single-phase conductor 20 into a small current of the secondary side is fixedly installed in the current transformer cover 30, a plurality of inside the current transformer 40 Two tab terminals 42 are installed, and the discharge gap plate installed at the largest tab terminal 42 of the tab terminals 42 is removed, and an insulating ring is formed between the current transformer 40 and the outer circumferential surface of the tank 10. 34) is installed.

A feature of the present invention having the above structure is that the current transformer 40 is provided on the outer circumferential surface of the tank 10 and covers the outside of the current transformer 40 with the cover 30, and the current transformer (by the cover 30) 40) It is easy to check and repair the current transformer 40 by preventing moisture from penetrating the terminal board and opening one side of the cover 30, so that a separate discharge gap plate can be removed from the tab terminal 42. It is.

The tank 10 is to insulate the single phase conductor 20 by enclosing the SF6 gas therein and passing the single phase conductor 20 at a predetermined distance from the inner wall of the tank 10.

The cover 30 is parallel to each other at a predetermined interval with a support plate 31 fixedly installed radially perpendicularly to the outer circumferential surface of the tank 10 and the support plate 31 at an upper portion of the support plate 31. The upper plate 32 is fixed to the outer circumferential surface of the tank 10 and a vertical cover 33 that is detachably coupled to the support plate 31 and the upper plate 32 to form a closed space, the support plate The current transformer 40 is seated and fixed to 31 so that the outside of the current transformer 40 can be blocked from the outside.

The current transformer 40 is fixedly installed on the support plate 31 of the cover 30, the outer peripheral surface of the tank 10 is contacted via an insulating ring 34, the upper portion of the current transformer 40 fixed bracket ( 35 to be fixed, and the fixing bracket 35 is fixed and supported by the fixing studs 36 so that the current transformer 40 is fixedly installed in the cover 30.

The current transformer 40 is composed of an iron core enameled copper wire and an insulated paper, and an insulation paper is wound around the iron core, and an enameled copper wire is wound thereon, the insulation paper is wound again, and a glaze is applied thereon, followed by drying. When power is applied to the single-phase conductor 20, current flows through the iron core of the current transformer 40 due to electromagnetic induction, and current flows through the enamelled copper wire, and a relay or a meter is connected to a terminal drawn out of the enameled copper wire. It is.

That is, the current transformer 40 is installed in the atmosphere and treated with a special diaphragm (non-ferrous metal) to convert a large current into a small current by linking the secondary winding without leakage of magnetic flux generated by the current flowing in the primary conductor. .

On the other hand, as shown in Figure 5, since the current transformer 40 is installed in the atmosphere, the discharge gap plate used when installed in the gas is unnecessary, the maximum tap terminal 42 of the tap terminal 42 of the current transformer terminal box 41 By removing the discharge gap plate provided in the above), the gap between the adjacent discharge gap plate and the discharge gap plate is changed so that erroneous discharge can be prevented.

As described above, according to the current transformer external gas insulated switchgear according to the present invention, the maintenance of the current transformer is easy by installing the current transformer on the outside of the tank, and by covering the outside of the current transformer to prevent moisture from penetrating from the outside. It is possible to prevent the malfunction of the circuit breaker and to remove the discharge gap plates provided at both ends of the tap terminal of the current transformer, thereby eliminating the erroneous discharge caused by the discharge gap plate, thereby improving the operation reliability of the protection relay.

Claims (1)

Single-phase conductor 20 is penetrated in the tank 10 filled with gas, and a current transformer for converting the large current flowing in the single-phase conductor 20 into a small current on the secondary side through a plurality of tab terminals 42 installed therein. In the gas insulated switchgear provided with (40), to prevent the spread of electrical accidents in the event of failure of the ultra-high voltage transmission line, and to open and close the line during the inspection of equipment such as transformers, The current transformer 40 is installed outside the tank 10 so as to be installed in the atmosphere, and discharge gap plates are not provided at both ends of the tab terminal 42 of the current transformer 40, and the current transformer 40 is located outside the current transformer 40. Current transformer external gas insulated switchgear, characterized in that provided with a cover 30 for sealing the 40.