JPH053726B2 - - 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 circumferential 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 a vaporization pipe connects the upper part of the vaporization chamber to the vaporized refrigerant inlet of a radiator installed outside the transformer, and the liquefied refrigerant outlet of the radiator and the vaporization chamber are connected by a liquid pipe line, and the vaporization chamber,
A refrigerant is sealed in a circulation system consisting of a gas pipe, a radiator, and a liquid pipe, and the liquefied refrigerant outlet of the liquid pipe opens toward the inner wall at the upper part of the vaporization chamber, and the liquid pipe is located at the upper part of the inner wall. A loop-shaped protrusion or groove is provided that extends around the outer surface of the inner wall so as to be inclined downward from the liquefied refrigerant outlet position.

This device guides the liquefied refrigerant flowing out from the outlet of the liquid pipe to the entire outer circumference of the inner wall using loop-shaped protrusions or grooves, and causes the liquefied refrigerant to flow down from there along the outer surface of the inner wall, where it is vaporized. It uses the latent heat of time to efficiently cool the air. The vaporized refrigerant enters the radiator through the gas line, where it liquefies, and then returns to the vaporization chamber through the liquid line.

〔Example〕

1 and 2 show one embodiment of the 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 an inner wall 16 and an outer wall 17. The vaporization chamber 18 is connected to the vaporized refrigerant inlet of a radiator (condenser) 19 installed above the transformer 11 by a gas pipe 20, and the liquefied refrigerant outlet of the radiator 19 is connected to the vaporization chamber 18. are connected by a liquid conduit 21. A heat radiating finned tube 22 is provided in the radiator 19 to communicate the gas pipe 20 and the liquid pipe 21 . As a result, the vaporization chamber 18 - gas pipe line 20 - radiator 19 - liquid pipe line 2
1-A closed circulation system is constituted of a vaporization chamber 18, in which a refrigerant such as Freon or water is sealed.

Further, the liquid pipe line 21 is bent into a U-shape within the vaporization chamber 18, and the liquefied refrigerant outlet thereof opens toward the inner wall 16 at the upper part of the vaporization chamber 18. Furthermore, a loop-shaped protrusion 23 is provided on the upper part of the inner wall 16 and extends around the outer surface of the inner wall 16 so as to be inclined downward from the liquefied refrigerant outlet position of the liquid pipe line 21 . The protrusion 23 is formed, for example, by forming a linear body into a loop shape and welding it to the inner wall 16.

The refrigerant sealed in the circulation system is cooled and liquefied when it exits the radiator 19, and this liquefied refrigerant is led to the vaporization chamber 18 by the liquid pipe 21,
It flows out from the outlet to the top of the protrusion 23. Since the protrusion 23 is inclined downward from there, the liquefied refrigerant is guided by the protrusion 23 and spreads around the entire circumference of the inner wall 16, and flows down from there to the inner wall 16.
Wet the entire surface. The liquefied refrigerant flowing down the outer surface of the inner wall 16 transfers heat from the inner wall 16 and partially vaporizes.
The remainder accumulates at the bottom of the vaporization chamber 18, but this too is gradually vaporized by heat from inside. Note that 24 is vaporization chamber 1
8 shows the liquefied refrigerant accumulated at the bottom. The vaporized refrigerant enters the radiator 19 from the upper part of the vaporization chamber 18 through the gas pipe 20, where it is condensed and circulated again along the above-mentioned path.

The transformer 11 in the above embodiment is installed, for example, underground, and the radiator 19 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 protrusion 23 that guides the liquefied refrigerant all around the oil surface be installed above the oil level. Furthermore, the lower end of the gas pipe 20 (the inlet of the vaporized refrigerant) is the liquid pipe 21.
It is preferable to position it above the outlet of the vaporizing chamber 18, particularly preferably at the top of the vaporization chamber 18.

In the above embodiment, the liquid pipe line 21 is connected to the vaporization chamber 18.
The reason why the inner part is bent into a U-shape is to prevent the vaporized refrigerant in the vaporization chamber 18 from entering the liquid pipe line 21 by storing the liquefied refrigerant in the U-shaped part.

FIG. 3 shows another embodiment of the invention. In this device, a groove 25 is formed on the upper outer peripheral surface of the inner wall 16 instead of the protrusion 23 in the above embodiment. The other configurations are the same as those of the above embodiment.

FIG. 4 shows yet another embodiment of the invention. This device has a mesh 26 on the outer surface of the inner wall 16 below the protrusion 23.
It is wrapped around. In this way, the liquefied refrigerant that has flowed down from the protrusions 23 is further spread around the entire circumference of the inner wall 16 by the net 26, so that
It has a great effect of evenly cooling the entire circumference.

〔Effect of the invention〕

As explained above, according to the present invention, the peripheral wall of the tank has a double structure, a refrigerant vaporization chamber is formed between the inner wall and the outer wall, and a loop-shaped protrusion or Since the oil-filled transformer is cooled by flowing liquefied refrigerant from the groove along the inner wall, 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 the drawing]

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 -
A line sectional view, FIGS. 3 and 4 are sectional views of main parts showing other embodiments of the present invention, and FIG. 5 is a partially cutaway perspective view showing a conventional oil-filled transformer. 11 - oil-filled transformer, 13 - tank, 14 - insulating oil, 16 - inner wall, 17 - outer wall, 18 - vaporization chamber,
19 - radiator, 20 - vaporization pipe line, 21 - liquid pipe line, 23 - protrusion, 24 - liquefied refrigerant, 25 - groove, 2
6 ~ Net.

Claims (1)

[Claims] 1. The peripheral wall of the tank of the oil-filled transformer is made into a double structure, and a refrigerant vaporization chamber is formed between the inner wall and the outer wall,
The upper part of the vaporization chamber and the vaporized refrigerant inlet of a radiator installed outside the transformer are connected by a gas pipe, and the liquefied refrigerant outlet of the heat radiator and the vaporization chamber are connected by a liquid pipe. , a refrigerant is sealed in a circulation system consisting of the vaporization chamber, a gas pipe, a radiator, and a liquid pipe, and the liquefied refrigerant outlet of the liquid pipe is opened toward the inner wall at the upper part of the vaporization chamber, and the refrigerant is opened at the upper part of the inner wall. 1. A cooling device for an oil-filled transformer, characterized in that a loop-shaped protrusion or groove is provided around the outer surface of the inner wall so as to be inclined downward from the liquefied refrigerant outlet position of the liquid pipe. 2. The device according to claim 1,
The liquid pipe line is bent into a U-shape inside the vaporization chamber. 3. The device according to claim 1 or 2, in which a net is wound around the outer surface of the inner wall below the protrusion or groove.