JPS63272022A - Gas insulated transformer - Google Patents

Abstract

PURPOSE:To condense coolant gas containing noncondensing insulating gas efficiently, suppress the pressure rise in an outer shell and maintain excellent cooling performance by a method wherein the noncondensing insulating gas and the condensing coolant gas filling the outer shell are blown into a cooler or the low temperature coolant liquid in a reservoir. CONSTITUTION:In a gas insulated transformer constituted by an outer shell 3 in which a core 1 and a coil 2 are housed and which is filled with noncondensing insulating gas and condensing and electrically insulating coolant, an outside cooler 4 or a reservoir in the outer shell 3 which is filled with the coolant liquid 9 and a means 5 by which the coolant liquid 9 in the cooler 4 or in the reservoir is cooled are produced. Further, pipes 15 and 17 and a blower 16 by which mixed gas 8 of the non-condensed coolant gas and the noncondensing insulating gas in the outer shell 3 is supplied into the cooler 4 or into the coolant liquid 9 in the reservoir and a pump 12 and pipes 11 and 13 by which the coolant liquid 9 in the cooler 4 or in the liquid sink is sucked and supplied to the upper parts of the core 1 and the coil 2 are provided.

Description

Detailed Description of the Invention [Purpose of Clarification] (Field of Industrial Application) The present invention provides an insulating gas that is non-condensable in the operating temperature range of a transformer, and an insulating gas that is condensable in the same temperature range. The present invention relates to a gas insulated transformer in which an envelope is filled with a cooling medium that also has properties.

(Prior Art) Conventionally, transformers have been filled with insulating gas or insulating oil for electrical insulation and cooling. However, the large G-1 of the transformer
As the heat loss increases, the loss of heat generated from the iron core and coil increases, and in the case of insulating gas9), attempts are made to maintain cooling performance by increasing the flow rate, but as the flow rate increases, the circulating power increases. Therefore, there are limits. Furthermore, although this restriction is less strict than that of insulating gas for insulation and edge bending, the specific ratio of insulating oil is slightly larger than that of gas, so the transformer 6-layer 1 becomes excessive.

Therefore, in order to solve the above problems, f&Kin has added 7JO to the conventionally used 41!3f&gas such as SF and gas.
Some transformers are operated by filling an envelope with a cooling medium that is vaporous or condensed within the operating temperature range of the transformer and has excellent insulation properties, such as fluorocarbons. This is done by - emitting a cooling medium by spraying the core and coils with a cooling medium or by immersing them in a cooling medium liquid.

Using the latent heat of vaporization at that time, the loss heat generated by damage from the iron core and coil is efficiently removed, and the cooling that evaporates and becomes gas.
& The body is condensed using an external cooler, etc., and the heat is discarded into the atmosphere.

A row of this conventional transformer is shown in FIG. The iron core 1 and the coil 2 are housed in an outer enclosure 43, and the coil 2 is immersed in an inner container 10 filled with a coolant liquid 9. Further, the upper surface of the inner container 10 is opened and the coolant liquid 9 overflows and collects at the bottom of each of the outer enclosures 13,
1 and is sucked in by a pump 12 and sprayed through a nozzle 14 provided above the iron core 1 and coil 2 through the entire piping 13. The cooling medium evaporated by the heat loss generated by the iron core 1 and the coil 2 becomes a gas and fills the surrounding container 3, forming a mixed gas B together with the non-condensable insulating gas that was originally filled. This mixed gas 8 is sucked through a pipe 7 by a blower (not shown) and supplied to the cooler 4. Here, cooling water is supplied to the cooler 4 through a pipe 5.

Here, only a part of the cooling medium gas in the mixed gas 8 is condensed, becomes a liquid, and returns to the bottom of the surrounding container 3. As described above, the heat loss generated in the iron core 1 and the coil 2 is discarded from the cooler 4 to the atmosphere.

However, it is known that if a non-condensable gas is contained even briefly in a condensable gas, the condensation efficiency is significantly reduced. That is, as shown in FIG. 5, the horizontal axis represents the opening containing non-condensable gas.

The vertical axis is the condensing heat transfer coefficient α when non-condensable gas is included, and the value α when non-condensable gas is not included. Taking the ratio to .

The heat transfer coefficient is 172-115 depending on the non-condensable gas used.
It will drop to . Therefore, in order to sufficiently remove the lost heat, a problem arises in that the cooler becomes large in size, and when the lost heat cannot be removed sufficiently, the pressure inside the envelope 3 increases.

(Problems to be Solved by the Invention) In the above conventional technology, the cooling medium becomes difficult to condense due to the non-condensable gas, and as a result, the cooling performance is significantly reduced and the pressure inside the envelope increases. In order to maintain cooling performance, the cooler and its operating power have become thicker.The object of the present invention is to improve the above-mentioned drawbacks and provide a gas insulated transformer with good cooling performance.

[Structure of the invention]

(Means for Solving the Problems) In the transformer according to the present invention, the non-condensable insulating gas and the condensable cooling medium gas filled in the envelope are pumped into the cooler or the liquid reservoir using a blower. The problem is solved by blowing into the coolant liquid.

(Function) Since the non-condensable gas-rich refrigerant gas is blown into the cooled refrigerant liquid and the two are brought into direct contact with each other, the condensation efficiency can be improved. As a result, cooling performance is improved, pressure rise within the envelope can be suppressed, and good cooling performance can be maintained.

(Example) A third embodiment of the present invention is shown in FIG. 3, with the first real I& column of the present invention being shown in FIG. 1 and the second real power column of the present invention being the second factor. Note that in FIGS. 1, 92, and 3, the same components as in FIG. 4 are designated by the same numbers, and explanations thereof will be omitted.

In a first embodiment of the present invention, as shown in FIG.

A mixed gas 8 of a non-condensable insulating gas and a condensable cooling medium gas, which is filled in the outer container 3, is drawn in by a blower 16 through a pipe 15 and cooled in the cooler 4 through a suction pipe 17. Blow into the medium liquid 9. Here, the coolant gas contained in the mixed gas 8 comes into direct contact with the cooled coolant liquid 9, so Ii! Easy to shrink. or.

The non-condensable rare green gas and the uncondensed cooling medium gas are also efficiently cooled and returned to the outer enclosure 3 by the piping 19 and the blower 1 (not shown). The loss heat removed by the iron core 1 and the coil 2 is discarded into the atmosphere by cooling the piping 5 or the like. on the other hand.

In the cooling a4, the volume of the cooling medium liquid increases by the amount of condensation of the cooling medium gas, so piping 18 is provided to return the cooling medium to the bottom of each outer enclosure 3 accordingly.

The second real power column of the present invention is! As shown in Figure 7M2.

Distribute the cooling medium liquid 9 collected at the bottom of the outer enclosure 8 container 3 - i ¥20
It is supplied to the cooler 4 via the suction pipe 1122t by the pump 21 and cooled. Further, from the cooler 4 to the pipe 23
It is sucked in by the pump 24 through the piping 25. It is sprayed onto the upper part of the iron core 1 and the coil 2 through the nozzle 14. This embodiment is basically the same as the embodiment shown in FIG. 1, but a low-temperature cooling medium liquid can be sprayed. Although not shown in the figure, as in the first embodiment shown in FIG.
A pipe 18 may be provided for returning the water to the bottom of the surrounding container 3.

A third embodiment of the present invention is shown in Figure 1g3.

Cold water is supplied via piping 28 to a liquid reservoir 26 formed at the bottom of the surrounding container 3 to cool the cooling medium liquid.

The mixed gas 8 in the surrounding σ reactor 3 is sucked in by the blower 16 through the distribution line 1915, and is fed to fy, 'f through the distribution line f27t-.
It is blown into the cooling medium of section Ii 26, where it is condensed and cooled. 2. Piping 27 has many small holes [! ! Since the two air bubbles rise while colliding with the distribution f28, the cooling efficiency is further improved. In addition, in the case of one row, there is no need to worry about installing a new external cooler.

〔Effect of the invention〕

According to the present invention, the non-condensable insulating gas T-gas and the cooling medium gas can be efficiently condensed, suppressing the pressure rise inside the envelope, and maintaining good cooling performance.

As a result, it is possible to provide a transformer with good cooling performance even if it is used in a large-capacity heating transformer, and the economical efficiency of the transformer can be improved.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a first embodiment of the invention. FIG. 2 shows a schematic diagram of a second embodiment of the invention, and FIG. 3 shows a third i4. FIG. 4 is a schematic diagram showing a row of conventional transformers, and FIG. 5 is a diagram showing the influence of non-condensing gas having 11 m characteristics. l...iron core, 2...coil, 3...envelope, 4...
...Cooler, 5...Cold water piping, 8...1 Gas, 9
...Cooling medium liquid, 10...Internal float, 12...Pump, 14...Nozzle, 16...Blower, 15...
・1 meter gas intake arrangement. 17...Mixed gas blowing pipe, 18...Cooling medium liquid return pipe'11.19...Mixed gas return pipe, 26...
・e, Tamabe. 27...Mixed gas blowing piping, 28...Cold water piping. Agent Patent Attorney Nori Ken Yudo Hikaru Matsuyama 2 Figure 1/ f14 Figure 2

Claims (1)

[Claims] In a gas-insulated transformer in which an iron core and a coil are housed in an envelope and filled with a non-condensing insulating gas and a cooling medium having electrical insulation and condensing properties, external cooling is performed by filling the condensed cooling medium liquid. a liquid reservoir in the cooler or the liquid reservoir; a means for cooling the coolant liquid in the cooler or in the liquid reservoir; and a means for cooling the coolant liquid in the cooler or in the liquid reservoir. piping and a blower for supplying a mixed gas of the uncondensed cooling medium gas in the outer container and the non-condensable insulating gas to the cooling medium; A gas insulated transformer comprising a pump and piping for sucking in the coolant liquid and supplying the coolant liquid to the upper part of the iron core and the coil.