JPH053728B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a cooling device for an oil-filled transformer.

[Prior art and its problems]

A conventional oil-filled transformer is shown in FIG. 1 is a transformer body consisting of an iron core 2 and a coil 3, and 4 is a tank that houses it. The tank 4 contains approximately eight parts of insulating oil 5, and the space above it is filled with nitrogen gas 6 to prevent deterioration of the insulating oil. The transformer body 1 is immersed in insulating oil 5, and heat generated by copper loss and iron loss is transferred to the heat radiating ribs 7 and the like on the surface of the tank 4 by convection of the insulating oil 5, and is radiated.

In this way, conventional oil-filled transformers are cooled by natural heat radiation from the tank surface, so it is necessary to create space around the tank for heat radiation.For example, in underground transformers, etc. It was difficult to secure that space. Furthermore, since heat is naturally dissipated from the tank surface, there is a problem that the cooling efficiency is poor.

[Means for solving problems and their effects]

The present invention provides a cooling device for an oil-filled transformer that solves the problems of the prior art as described above, and has a structure in which the peripheral wall of the tank of the oil-filled transformer has a double structure, and its inner wall and A refrigerant vaporization chamber is formed between the outer walls, and an annular conduit having liquefied refrigerant outflow holes around the entire circumference is provided on the upper part of the inner wall in the vaporization chamber, and a refrigerant is installed outside of the annular conduit and the transformer. The radiator is connected to the radiator by a liquid pipe, and the upper part of the vaporization chamber and the radiator are connected by a vaporization pipe, and the circulation consists of the vaporization chamber, the gas pipe, the radiator, the liquid pipe, and the annular pipe. This system is characterized by a refrigerant sealed in the system.

This device allows liquefied refrigerant to flow out from outflow holes provided around the entire circumference of the annular pipe, flows it down along the surface of the inner wall, and efficiently cools the refrigerant by utilizing the latent heat generated when it evaporates. It is. The vaporized refrigerant enters the radiator through the gas line, where it liquefies, and then returns to the annular line through the liquid line.

〔Example〕

1 to 3 show one embodiment of the present invention. In the figure, 11 is an oil-filled transformer, 12 is a transformer body consisting of an iron core and a coil, 13 is a tank,
14 is insulating oil, and 15 is nitrogen gas. tank 1
3 has a double-walled peripheral wall, and a refrigerant vaporization chamber 18 is formed between the inner wall 16 and outer wall 17. In addition, the inner wall 16 in the vaporization chamber 18
An annular conduit 19 is attached to the upper part of the annular conduit 19, and a large number of liquefied refrigerant outlet holes 20 are formed around the entire circumference of the annular conduit 19. Note that the outflow hole 20
is formed upward on the upper surface of the annular conduit 19.

The annular conduit 19 is connected to a radiator 21 installed above the transformer 11 by a liquid conduit 22 . Further, the upper part of the vaporization chamber 18 and the radiator 21 are connected by a gas pipe 23. Inside the radiator 21, a liquid conduit 22 and a gas conduit 23 are connected by a tube 24 with heat dissipation fins. The circulation system consisting of the vaporization chamber 18 - gas pipe 23 - radiator 21 - liquid pipe 22 - annular pipe 19 - vaporization chamber 18 is sealed, and a refrigerant such as freon or water is sealed inside. There is.

The refrigerant sealed in the circulation system is cooled and liquefied when it exits from the radiator 24, and this liquefied refrigerant enters the annular pipe 19 through the liquid pipe 22.
Therefore, it spreads over the entire circumference of the annular conduit 19. Since the annular pipe 19 has outflow holes 20 distributed around its entire circumference, the liquefied refrigerant overflowing from the outflow holes flows down while wetting the entire circumferential surface of the inner wall 16. While flowing down, the liquefied refrigerant transfers heat from the inner wall 16 and partially vaporizes, and the remainder accumulates at the bottom of the vaporization chamber 18, but this too gradually vaporizes due to the heat from inside. Note that 25 is the vaporization chamber 18
This shows the liquefied refrigerant that has accumulated at the bottom. The vaporized refrigerant enters the radiator 21 from the upper part of the vaporization chamber 18 through the gas pipe 23, where it is condensed and circulated again through the above-mentioned path.

The transformer 11 in the above embodiment is installed, for example, underground, and the radiator 21 is installed above ground.

Since the upper surface of the insulating oil 14 reaches its highest temperature due to convection, it is preferable that the annular pipe 19 through which the liquefied refrigerant flows out is installed above the oil level. Further, the lower end of the gas pipe 23 (the inlet of the vaporized refrigerant) is connected to the annular pipe 19.
It is preferable to locate it higher up, particularly at the top of the vaporization chamber 18.

In the above embodiment, the liquefied refrigerant outflow hole 20 of the annular pipe is formed on the upper surface of the annular pipe 19 because the vaporized refrigerant in the vaporization chamber 18 enters the annular pipe 19 and flows back into the liquid pipe 22. This is to prevent this from happening. To ensure backflow prevention, the fourth
As shown in the figure, it is preferable that the vicinity of the refrigerant outlet end of the liquid conduit 22 is bent into a U shape, and the outlet end is connected to the lower surface side of the annular conduit 20.

Note that the liquefied refrigerant outflow holes of the annular pipe may be formed as a large number of small holes as in the above embodiment, but may also be formed in the form of slits continuous in the circumferential direction.

〔Effect of the invention〕

As explained above, according to the present invention, the peripheral wall of the tank is made into a double structure, a refrigerant vaporization chamber is formed between the inner wall and the outer wall, and the annular pipe provided at the upper part of the inner wall in the vaporization chamber is connected to the inner wall. Since the oil-filled transformer is cooled by flowing liquefied refrigerant along the tank, there is no need to create space for natural heat radiation around the tank, which has the advantage of reducing the installation space. Also, since cooling is performed using latent heat when the refrigerant vaporizes, it has the advantage of high cooling efficiency.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a cooling device for an oil-filled transformer according to an embodiment of the present invention, and FIG. 2 is a -
3 is an enlarged sectional view of the upper part of the vaporizing chamber of the same device, FIG. 4 is a sectional view of the main part showing another embodiment of the present invention, and FIG. 5 is a conventional oil-filled transformer. FIG. 3 is a partially cutaway perspective view. 11 - oil-filled transformer, 13 - tank, 14 - insulating oil, 16 - inner wall, 17 - outer wall, 18 - vaporization chamber,
19 ~ Annular pipe line, 20 ~ Liquefied refrigerant outflow hole, 21 ~
radiator, 22 - liquid pipe line, 23 - gas pipe line, 25
~Liquid refrigerant.

Claims (1)

[Claims] 1. The peripheral wall of the tank of the oil-filled transformer has a double structure, and a refrigerant vaporization chamber is formed between the inner wall and the outer wall,
An annular conduit having liquefied refrigerant outflow holes around the entire circumference is provided in the upper part of the inner wall in the vaporization chamber, and this annular conduit and a radiator installed outside the transformer are connected by a liquid conduit, The upper part of the vaporization chamber and the radiator are connected by a vaporization pipe, and the vaporization chamber, the gas pipe,
A cooling device for an oil-filled transformer, characterized in that a refrigerant is sealed in a circulation system consisting of a radiator, a liquid pipe, and an annular pipe. 2. The device according to claim 1,
The liquefied refrigerant outflow hole of the annular pipe is formed on the top side of the annular pipe. 3. The device according to claim 2,
The refrigerant outlet end of the liquid pipe is connected to the bottom side of the annular pipe.