JPH08241818A - Oil-immersed electric apparatus - Google Patents

Abstract

PURPOSE: To provide an oil-immersed transformer, wherein an abnormality developed inside the transformer can be detected in an early stage. CONSTITUTION: The connecting opening of the upper part of a tank main body 5 with a duct 7 provided above the tank main body 5 and the connecting opening of the duct 7 with a conservator 8 are arranged at a diagonal position to each other, a gas stop 16 which gathers gas bubbles is provided to the inner side of the upper cover 15 of the duct 7, so that the connecting opening of the upper part of the tank main body 5 with the duct 7 is shifted from the connecting opening of the duct 7 with the conservator 8 when an inner trouble occurs in the transformer, and decomposed gas is restrained from passing through. Furthermore, decomposed gas passing through the connecting opening is collected by the gas stop 16 provided to the upper cover 15 and restrained from entering the conservator 8, so that decomposed gas gathers in a gas detection relay 14 from the duct 7 passing through a blowoff tube 12, and trouble can be early detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil-filled electric device suitable for a disaster prevention structure of a substation.

[0002]

2. Description of the Related Art In recent years, a three-phase transformer has been integrated as the size of the transformer has been increased due to higher voltage and larger capacity, and the transportation conditions to the transformer installation site such as mountainous areas, urban areas and underground substations have deteriorated. In many cases, it is difficult to transport.

Therefore, a three-phase transformer in which three single-phase transformers are arranged side by side has come to be adopted, but during transportation, a single-phase transformer and a conservator with a duct (in some cases, the duct and the conservator are also used). (Divided) is individually divided and transported.

On the other hand, in the oil-filled transformer, when a short circuit accident occurs inside the tank body and an arc occurs, the pressure inside the tank body rapidly rises due to the decomposition gas of the oil. In the case of a small internal short circuit accident, the above-mentioned pressure rise can be alleviated by the expansion amount of the tank body itself and the release of oil from the pressure release device. However, in the case of an internal short-circuit accident in a transformer connected to a large system capacity, a large amount of oil decomposition gas was generated,
In some cases, the sudden increase in pressure cannot be alleviated by the expansion amount of the tank body and the release of oil from the pressure relief device.
The tank body is destroyed, hot gas and oil are ejected, and the hot gas and oil touch oxygen in the atmosphere and ignite,
It may lead to secondary disasters such as fire accidents.

In particular, as described above, in the division transport type transformer in which three single-phase transformers are combined, the tank body of the single-phase transformer has a small volume and a small surface area. It has become difficult to secure a sufficient amount of expansion to reduce the pressure rise by itself.

Therefore, conventionally, by providing the tank main body and the conservator and the duct connecting them, the expansion amount of the tank main body alone, the expansion amount of the duct, and the pressure relief space of the conservator are secured. .

However, in the integral connection structure of the tank main body, the duct and the conservator, in order to quickly guide a rapid pressure rise due to an internal short-circuit accident of the transformer to the pressure relief space in the conservator, the pressure relief space is reached. Since it is necessary to increase the cross-sectional area of the connecting opening and shorten the length of the connecting part and the conduit, a structure was adopted in which the connecting opening on the upper part of the tank body and the connecting opening on the lower part of the conservator were located in a straight line. .

When an accident occurs inside the transformer,
Oil and insulation are thermally decomposed to generate gas. This gas enters the lead connection duct from the upper connection opening of the single-phase transformer, and is further collected from the pressure relief pipe attached to the upper side surface of the lead connection duct to the gas detection relay attached to the upper part to perform gas detection, It is configured to detect an abnormality inside the transformer at an early stage.

[0009]

As described above, in the conventional connecting structure of the transformer, the lead duct and the conservator, the transformer and the lead duct and the connecting opening of the lead duct and the conservator are located at the same position. At the time of an accident in the transformer, gas from the transformer tank body enters the conservator through the two connection openings and accumulates on the lower surface of the conservator rubber bag. The lower surface of the conservator rubber bag expands and contracts according to the transformer oil temperature, so it becomes uneven, and the gas accumulated on the lower surface of the rubber bag cannot move from here, so it cannot be collected in the gas detection relay early and the transformer There was a problem that an abnormality inside the container tank body could not be detected early.

The present invention has been made to solve the above problems, and its object is to provide a transformer tank by a structure in which gas emitted from the tank body does not enter the conservator in the event of an internal accident in the transformer tank body. An object of the present invention is to provide an oil-filled transformer that can detect an abnormality inside the main body at an early stage.

[0011]

In order to achieve the above object, the present invention provides a tank main body containing the contents of static electric equipment and insulating oil, and a pressure relief space for a rubber bag arranged above the tank main body. In a oil-filled electrical device comprising a conservator having, a duct connecting the tank main body and the conservator, a pressure release device installed from the upper part of the duct through an oil pipe, and a gas detection relay, The connection opening with the duct and the connection opening with the duct and the conservator, which are provided on the upper part of the tank body, are arranged diagonally to each other and collect gas bubbles inside the duct upper surface cover. It is characterized by having a gas stop.

[0012]

[Operation] When an internal accident occurs in the single-phase transformer, the decomposed gas of the oil generated in the tank main body becomes bubbles and enters the duct through the connection opening in the upper part of the tank main body. When this gas flows from the duct to the conservator, the connection opening between the upper part of the tank main body and the duct and the connection opening between the duct and the conservator are misaligned, so that passage of the decomposition gas is suppressed. Further, the decomposition gas that is about to pass through the connection opening is collected by the gas stopper of the duct upper surface cover, and the invasion into the conservator is suppressed. In this way, since the decomposed gas is suppressed from entering the conservator from the duct, it collects in the gas detection relay from the duct through the pressure relief pipe, and the occurrence of an internal accident in the transformer can be detected early.

[0013]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a configuration diagram of a special three-phase split oil-filled transformer which is an embodiment of the present invention, and shows a state in which each phase is not connected. FIG. 2 is a view seen from the direction A in FIG.

In FIG. 1, each single-phase transformer TA, TB,
TCs are configured the same. That is, the transformer contents 3 in which the winding 2 is wound around the iron core 1 are stored in the transformer tank body 5 together with the insulating oil 4. Each single-phase transformer TA, TB,
The connection opening 6 is provided on the upper part of the tank body 5 of the TC,
The connection opening 6 and the connection opening 9 of the conservator 8 are connected by a duct 7. Further, since the connection opening 6 and the connection opening 9 are arranged at positions diagonal to each other,
The connection openings are offset from each other so that they are not aligned.

A rubber bag 11 is provided in the conservator 8 to secure a pressure-relief space 10 in case of a short-circuit accident inside the transformer.
Is stored. Further, the duct 7 has a pressure relief pipe 12
A pressure release device 13 and a gas detection relay 14 are provided via the. On the inner surface of the upper surface cover 15 of the duct 7, and on the side of the connecting opening 9 of the conservator 8, a gas stopper 16 of a half rod is provided.
Is attached.

Next, the operation of this embodiment will be described.
When an arc occurs due to a short-circuit accident inside the transformer, the internal pressure rises sharply due to the decomposition gas of oil. The expansion amount at this time is absorbed by the tank body 5, the duct 7, the conservator 8 and the pressure-relief space 13. In addition, the gas generated at this time becomes bubbles and enters the duct 7 through the connection opening 6 of the tank body 5. When this gas enters the conservator 8 from the duct 7, it is difficult to enter because the connection opening 9 is displaced from the connection opening 6, and the passage of gas is suppressed.

Further, gas bubbles that are about to pass through the connection opening 9 are provided with a gas stopper 1 provided inside the upper surface of the duct.
6 and the invasion into the conservator 8 is suppressed. The suppressed gas collects from the duct 7 through the pressure release pipe 12 to the gas detection relay 14 so that the occurrence of an accident inside the transformer can be detected at an early stage.

[0018]

As described above, according to the present invention,
In the event of an internal accident in the transformer tank body, the upper connection opening of the single-phase transformer and the lower connection opening of the conservator were positionally offset, and a gas stop was installed on the inner surface of the upper duct to collect gas bubbles. The generated gas is less likely to pass from the duct to the conservator and collects at the gas detection relay from the duct, so that an internal accident in the transformer tank body can be detected early and reliably.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a view on arrow A in FIG.

FIG. 3 is a configuration diagram of a conventional oil-filled transformer.

[Explanation of symbols]

1 ... Iron core, 2 ... Winding, 3 ... Transformer contents, 4 ... Insulating oil, 5
... tank main body, 6 ... connection opening, 7 ... duct, 8 ... conservator, 9 ... connection opening, 10 ... pressure relief space, 11 ... rubber bag, 12 ... pressure release pipe, 13 ... pressure release device, 14 ... gas detection relay , 15 ... cover, 16 ... stop gas.

Claims (1)

[Claims] 1. A tank main body accommodating the contents of static electric equipment and insulating oil, a conservator having a pressure-relief space for a rubber bag arranged above the tank main body, and connecting the tank main body and the conservator. In an oil-filled electrical device including a duct, a pressure release device installed from the upper part of the duct through an oil pipe, and a gas detection relay, the connection opening between the duct provided on the upper part of the tank body and the The oil-filled electrical device, wherein the duct and the connection opening of the conservator are arranged diagonally to each other, and a gas stopper for collecting gas bubbles is provided inside the duct upper surface cover.