JPH05109544A - Gas insulation transforming station of reduced size - Google Patents

Abstract

PURPOSE:To make electric field control outside of a coil easier and to prevent impurities generated at a breaker, etc., from coming into the inside of the coil by providing a conductive shielding plate outside of the coil so as to provide a sealed structure except far an aperture of a part of an upper part. CONSTITUTION:A conductive shielding plate 18 is provided outside of a coil 11 wound around an iron core 12. Cooling gas 15 passes through only the tap part. A minimum aperture which does not obstacle cooling is provided and the remaining part is given a sealed structure so that the impurities generated at a barker, etc., may not get into the coil 11. Where a high voltage lead 19 is connected with a switching device, etc., the part between the high voltage lead 19 and the shielding plate 18 is sealed with a high voltage lead insulating material 20. The electric field is controlled with a general part of the coil 11 and the shielding plate 18 acting as earth electrodes, and a multi-insulating material arrangement structure provides insulation. As a result, insulation is easily attained in a transforming station having a very complex winding structure and invasion of impurities generated at a breaker, etc., is prevented.

Description

Detailed Description of the Invention

[0001]

The present invention relates to relates to a reduction type gas insulated substations containment insulating gas such as SF _6.

[0002]

2. Description of the Related Art In recent years, a compact gas-insulated substation (commonly called GI
S) has become widely adopted. The reason is that all the equipment that composes the substation is covered with a grounded metal case, there is no exposed part of the charged part of electricity, and it is safe, and accidents do not occur depending on weather conditions such as typhoons. That is the main reason. Furthermore, because the insulation strength of the insulating gas (usually SF ₆ gas is widely used) enclosed in the metal case is higher than that of air, it is possible to reduce the insulation distance between the voltage-applying parts or between the earth and This is due to the fact that a substation with a significantly reduced space can be obtained compared to a substation using ordinary aerial equipment.
However, how to make the substation as a whole small has become an extremely important issue from an economic point of view in Japan, where land prices have recently risen.

Therefore, until a few years ago, a single-phase type GIS was often used, but recently, a three-phase type GIS has also appeared. For example, the configuration diagram of the GIS of FIG. 4 and FIG. 5 and its single line connection diagram are known. 4 and 5, 1 is a transformer, 2 is a circuit breaker, 3 is a disconnector / grounding device,
Reference numeral 4 is a current transformer, 5 is an instrument transformer, 6 is a main bus, 7 is a power cable, and the transformers and the breaker section are separated from each other by a metal shell 17a. Further, a composite type device in which a plurality of devices, for example, a circuit breaker and a grounding device are incorporated as an integrated device has also appeared.

In this way, the ultimate form of increasing the degree of integration of each device and further reducing the size is to store the entire substation in one outer shell case, and store it in an S case.
It is to be enclosed with an insulating gas such as F ₆ . Such a "GIS that puts the whole substation in one room" itself has been proposed from an early stage, and as an example, Japanese Patent Publication No. 44-299.
No. 43 publication.

FIG. 2 is a block diagram assuming that the above-mentioned "GIS for putting the entire substation in one room" is realized, and FIG. 3 is a sectional view taken along line II-II of FIG. .. 2 and 3 remove the metal outer shell 17a of each of the components of the substation shown in FIG.
_This is an example of a substation with the configuration and arrangement when it is concentrated in a room containing ₆ gas. This substation has a voltage of 145K
In the example of V and transformer capacity of 2 × 60 MVA, the reduction effect is that the transformer and GIS occupy an area of 360 m ² and an occupancy volume of 3240 m ³ in the conventional substation shown in the figure.
In the example of FIG. 2, it becomes 96 m ² and 430 m ³ , respectively, and when expressed as reduction ratios, they are 27% (area) and 15% (volume), respectively.

However, there are some technical problems to be solved in the contents, and they have not been actually used yet. The technical issues are as follows.

(1) Since the dielectric strength of the insulating gas sealed in the substation improves in proportion to the pressure, it is usually 2
At present, it is used as a high pressure gas of up to 5 Kg / cm ² . The outer container that houses the equipment must be a pressure container that can withstand the pressure of this high-pressure gas. Such a pressure vessel can be manufactured in a small case that houses several devices, but it is not possible to manufacture a large container that can house several dozen or more devices in a composite manner like the entire substation. .. In addition, in order to facilitate the realization,
According to Japanese Patent Publication No. 29943, a spherical container having high pressure resistance is adopted as the outer shell container, but this is a technique that cannot be solved economically.

(2) Therefore, there is a method of giving up the use of high-pressure gas and enclosing a low-pressure gas, that is, a gas at atmospheric pressure at the expense of dielectric strength. Since there is a slight pressure difference between the inside and the outside of the container, it is necessary for the container to have a certain level of strength.
It has been considered necessary to have a spherical container as described in Japanese Patent No. 43 publication. However, in the case of such a spherical container, the arrangement of the equipment that constitutes the substation is restricted, and a space that cannot be used is left out, so that the degree of integration deteriorates. This, combined with the poor degree of reduction due to the poor dielectric strength of low-pressure gas, has not become a technology that overcomes the usual GIS.

(3) Storing all the components of the substation in one outer shell container means that the operator cannot enter the substation. It must be operated from outside the shell container. However, this operability, that is, the technology of physical actuation and electrical remote control has not been solved.

(4) Among the substation equipments housed in the outer shell, the transformer has a very complicated winding structure unlike other equipments, so that electric field control is difficult and the transformer is generated from the breaker portion or the like. When such impurities enter the inside of the winding, the insulation characteristics are significantly deteriorated. Therefore, a winding structure that prevents such impurities from entering the inside of the winding and facilitates electric field control is required.

Among the above technical problems, it is considered that the above (3) can be solved by using the recent unmanned technology using a robot or the technology of electrical and optical remote control.

[0012]

The present invention has been made in view of the above circumstances, and prevents (4) of the above technical problems, that is, prevents intrusion of impurities generated from a substation device housed in an outer shell. Another object of the present invention is to provide a reduced gas-insulated substation equipped with a transformer having a winding structure that facilitates electric field control.

[0013]

In order to achieve the above object, the present invention is intended for use in a substation such as a transformer or a circuit breaker in which an internal element is exposed to an insulating gas in an outer shell which is strong and airtight. In a compact gas-insulated substation with built-in equipment, a conductive shield plate is provided outside the winding of the transformer to prevent impurities generated from the circuit breaker from entering the inside of the transformer winding. It is characterized in that the structure other than the opening on the upper part of the winding has a hermetically sealed structure to enable electric field control of the transformer alone and dust prevention of impurities generated from the breaker part and the like.

[0014]

According to the present invention, in a compact gas-insulated substation with a high degree of integration, it is easy to insulate a transformer having a very complicated winding structure, and the intrusion of impurities generated from the breaker section or the like is prevented. Since this can be prevented, the reliability of the operation of the transformer and thus the operation of the gas-insulated substation can be significantly improved.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of an embodiment of the present invention. As shown in FIG. 1, the transformer 1 and the switchgear 14 are housed inside an outer shell 17. Transformer 1 that generates a large amount of heat
In order to cool efficiently mainly, the cooling gas 15 inside the outer shell 17, the gas-liquid heat exchange cooler 10 in which the cooling liquid 16 flows into the outside, and the cooling gas 15 forcibly inside the transformer. A cooling guide 13 for efficiently circulating the cooling gas 15 in the cooler 10 is provided between the blower 9 for circulating the cooling air and the lower part of the cooler 10. A conductive shield plate 18 is provided on the outside of the winding wire 11 wound around the iron core 12, and a cooling gas 15 passes through only the uppermost portion, and a minimum opening portion that does not hinder cooling is provided.
In the other part, impurities generated from the breaker part etc. are wound 11
A closed structure that does not enter inside. High voltage lead 1
At a portion where 9 is connected to a switchgear or the like, a high-voltage lead insulator 20 seals between the high-voltage lead 19 and the shield plate 18. Insulation between the general portion of the winding 11 and the shield plate 18 controls the electric field using the shield plate 18 as a ground electrode, and is insulated by a multiple insulator arrangement structure (not shown).

Next, the operation of this embodiment will be described.
By providing a conductive shield plate 18 on the outside of the winding 11 and forming a closed structure except for an opening at a part of the upper portion, it becomes easy to control an electric field outside the winding 11 and impurities generated from a breaker portion or the like Can be prevented from entering the inside of the winding. Further, since the structure for forcibly cooling the inside of the transformer is adopted, the upper opening of the shield plate 18 can be made small, so that the sealing effect against impurities is improved. Therefore, the reliability of operation of the transformer is significantly improved.

In the above embodiment, the case where the inside of the transformer is forcibly cooled has been shown, but the size of the upper opening of the shield plate must be made larger even in the case of natural circulation cooling without forced cooling. However, it is possible to adopt the same structure as the above-mentioned embodiment.

[0018]

As described above, according to the present invention,
In a compact gas-insulated substation with a high degree of integration, it facilitates the insulation of a transformer with a very complicated winding structure, prevents the intrusion of impurities generated from the breaker section, etc. The reliability of local operation can be significantly improved.

[Brief description of drawings]

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

FIG. 2 is a plan view of a building container type gas insulated substation to which the present invention is applied.

FIG. 3 is a sectional view taken along the line II-II in FIG.

FIG. 4 is a block diagram of a conventional GIS.

FIG. 5 is a single line connection diagram of FIG.

[Explanation of symbols]

1 ... Transformer, 2 ... Circuit breaker, 3 ... Disconnector / grounding device, 4 ...
Current transformer, 5 ... Instrument transformer, 6 ... Main busbar, 7 ... Power cable, 8 ... Connection busbar (gas insulation), 9 ... Cooling gas circulation blower, 10 ... Gas-liquid heat exchange cooler, 11 …
Transformer winding, 12 ... Transformer core, 13 ... Cooling guide, 1
4 ... Switchgear, etc., 15 ... Forced cooling gas, 16 ... Cooling liquid, 17 ... Outer shell, 18 ... Shield plate, 19 ... High voltage lead, 20 ... High voltage lead insulator.

Claims (1)

[Claims] 1. A reduction type gas-insulated substation in which a substation-equipped device, such as a transformer or a circuit breaker, whose internal elements are exposed to an insulating gas, is built in a strong and airtight outer shell. A conductive shield plate is provided on the outside of the winding, and a structure other than the opening above the winding is sealed to prevent impurities generated from the circuit breaker from entering the inside of the transformer winding. A compact gas-insulated substation that is capable of controlling the electric field of the device and preventing dust generated from the circuit breaker.