JPS6014493B2 - electromagnetic induction equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to electromagnetic induction equipment cooled by condensing cooling butterflies.

In order to improve the cooling efficiency of a transformer, it is important to increase the heat exchange efficiency between the transformer and its cooling medium. In the case of gas-insulated transformers, liquid coolants (hereinafter referred to as refrigerants) such as inert fluorinated organic compounds that can vaporize at the normal operating temperatures and pressures of the transformer are used to increase the efficiency of this heat exchange. ) is sprayed or dispersed onto heat-generating parts such as the core and windings of the transformer, and the evaporative cooling type gas insulated transformer is used, which cools the transformer by evaporating the coolant.

The basic structure of this evaporative cooling type gas insulated transformer will be explained using the example shown in FIG.

The transformer winding 1 and the iron core 2 are housed in a sealed container 3, and the inside of the container is filled with a gas 4 suitable for insulating the transformer, such as SF6 gas, at an appropriate pressure. Cold soot 6 is always stored at the bottom of the container 3. When the transformer is in operation, this soot 5 is pumped up by a pump 6 and sent through a conduit 7 to a sprayer 8 or other suitable spreader where it is sprayed or spread over the windings 1 and core 2 as closely as possible. . When this cooler 5 approaches or touches the winding 1 and the iron core 2 and is heated, it vaporizes until it reaches a vapor pressure corresponding to the temperature, and absorbs the heat generated by the winding 1 and the iron core 2. A method of cooling the winding 1 and the iron core 2 by utilizing the high heat exchange efficiency between the winding 1 and the iron core 2 and the cold soot 5 at this time is the basic method of the evaporative cooling type gas insulated transformer. The vaporized coolant radiates heat on the surface of the container 3 and the condenser 9, liquefies it again, and returns to the cold soot reservoir at the bottom of the container.

The soot 5, which is carried to the condenser 9 as shown by the arrow 10 and radiated heat there, flows as shown by the arrow EO11 and returns to the bottom of the container, where it is circulated again by the pump 6. By the way, in the case of the structure shown in FIG. 1, the liquefied refrigerant 5 is sent directly to the atomizer 8 by the pump 6, so the temperature of the cold soot 5 in the cold soot reservoir at the bottom of the container and the amount of atomization from the atomizer 8 are determined by the pump 6. The temperatures of the refrigerant 5 are almost the same, and are quite high, close to the temperature immediately after the vapor of the cold soot 5 liquefies.

This is because most of the heat dissipation on the surface of the condenser 9 and container 3 is used to lower the temperature of the refrigerant 5 vapor and SF6 gas, as well as to take away the latent heat of vaporization from the vapor and liquefy it. This is because the effect of lowering the temperature of the refrigerant 5 after this is not so great. In this way, when the temperature of the misted refrigerant 5 is high, the temperature difference between the winding 1 and the iron core 2 is small, and therefore the winding 1 and the iron core 2 due to contact with the refrigerant 5 are
cooling effect becomes smaller. It is rumored that if the temperature of the cold butterfly 5 is high and it is easy to evaporate, most of the cold butterfly 5 will be in the winding 1.
This evaporates in the upper part of the iron core 2, making it difficult to uniformly cool the entire winding 1 and the iron core 2. On the other hand, container 3
The internal pressure is the sum of the gas pressure of the gas 4 and the pressure of the steam of the soot 5, but from the viewpoint of the mechanical strength of the container 3, it is desirable that this sum of pressures be as small as possible. However, when the temperature of the cold container is high, the vapor pressure of the cold soot is high relative to that temperature, so the pressure inside the container increases, and the container needs to have high mechanical strength to withstand that pressure. The present invention was made for the purpose of improving the above-mentioned drawbacks.

An embodiment of the present invention will be described with reference to FIG. In the figure, numerals 1 to 11 are the same as conventional ones. A radiator 12 cools the soot 5 sent out by the pump 6 before it is discharged from the sprayer 8. This heat sink 1
2 may be one in which the length of the conduit 7 is increased to increase the contact area between the conduit 7 and the outside air. Alternatively, cooling fins or the like may be provided to increase the heat dissipation surface area, or forced cooling may be performed using a cooling fan. By providing the radiator 12, the temperature of the soot 5 discharged from the atomizer 8 can be lower than the temperature of the cold soot 5 that was in the refrigerant reservoir before passing through the radiator 12. In this way, by distributing cold soot that has been cooled to a low temperature, not only the cooling effect of the winding 1 and the iron core 2 is improved, but also the cold soot 5 evaporates only in the upper part of the winding 1 and the iron core 2. The winding 1 and the iron core 2 can be cooled more uniformly by appropriately selecting the amount of heat radiated by the radiator 12 and adjusting the temperature of the cold soot 5 so as not to cause the soot to cool. In addition, by lowering the temperature of the liner 5, the vapor pressure of the cold soot 5 can be lowered, which lowers the internal pressure of the container 3.
The mechanical strength required can be reduced. As described above, the present invention improves the cooling effect and performs uniform cooling by providing a radiator for cooling the liquefied cold soot in the shield return path of the soot and lowering the temperature of the cold soot. At the same time, the mechanical strength required by the container can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional electromagnetic induction device, and FIG. 2 is a block diagram showing an embodiment of the present invention. In the figure, 1 is a winding, 2 is an iron core, 5 is a refrigerant, 9 is a condenser, and 12 is a radiator. Note that the same reference numerals in each figure indicate the same or equivalent parts. Figure 1 Figure 2

Claims (1)

[Claims] 1. The windings and the iron core are housed in a sealed container, and an evaporative refrigerant is sprayed onto the windings and the iron core, the windings and the iron core are cooled by the latent heat of vaporization during evaporation, and the vaporized refrigerant is transferred to a condenser. 1. An electromagnetic induction device configured to liquefy the refrigerant, characterized in that a radiator for cooling the refrigerant in a liquid phase is provided in a circulation path of the refrigerant.