JPS5875810A - Leaf wound transformer - Google Patents

Abstract

PURPOSE:To equalize temperature distribution of a winding body, by a method wherein a leaf conductor and an insulation sheet are overlaid and wound to form a winding body, and a cooling duct and a heat pipe are installed within the winding body. CONSTITUTION:A leaf conductor 2 and an insulation sheet 3 are overlaid and wound thereby winding bodies of low tension side and high tension side are formed. An annular cooling duct 6 is installed within the winding bodies. The cooling duct contains a thin gap and is filled with a cooling medium 10. The cooling medium 10 is circulated from upper side through the cooling duct by means of a pump 7. Heat in the leaf winding bodies is eliminated by the cooling medium 10. The cooling medium subjected to the heat is cooled in a heat exchanger 8 by cooling water and then fed into the winding body by the pump 7. A heat pipe 18 is disposed at intermediate portion between the opposed cooling ducts for eliminating the heat from high temperature portion at lower side and radiates the heat to low temperature portion at upper side.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a foil-wound transformer formed by winding a foil-like conductor.

Foil-wound transformers have a good conductor space factor, so they have the advantage of being smaller and lighter than wire transformers.
In order to increase the voltage by 1% and increase the capacity, a cooling duct is built into the coil to feed a refrigerant with excellent insulation properties, and the heat generated due to loss in the foil is directly cooled down. is required.
Riku.

FIG. 1 shows an example of this cylindrical foil-wound transformer Oi. A low-voltage winding body 4 and a high-voltage winding body 5, which are formed by overlapping and winding a foil conductor 2 and an insulating sheet 3, are wound around the outside of an iron core l, and an annular cooling duct 6 is built into these windings.

There is a thin gap inside this cooling duct.
Cold such as FC75] fl114 is filled, and it is 9
, by the pump 7], and the Ofh heat inside the foil-wrapped roll is transferred to the refrigerant 14, and the high-temperature refrigerant is cooled by the cooling water 9 in the heat exchanger 8, and becomes a low-temperature medium. A refrigerant circulation cooling circuit is established by feeding the refrigerant into the cooling duct at the pongua.

The cooling duct 6 is made of metal such as stainless steel, and an insulated pipe 11 is used to connect it to the oil guide pipe 10, and the cooling duct 6 is insulated from the earth potential of the oil guide pipe 10, tank 12, etc. ing.

The cooling duct) 60 potential is electrically coupled to the same potential as the winding conductor because it is wrapped inside the winding.

The winding O insulation is sealed in the tank and there is nine insulation oil - is 8F.
- insulated from the gas by an insulating medium 13;

Note that in No. 111), OSs not directly related to the present invention are
The conductor lead wire and the bushing that leads it out to the outside of the tank are omitted.

Temperature ri of the refrigerant 14 in the cooling duct of the foil-wound transformer in upper le
As shown by the solid line LSD in FIG. 2, the moth becomes 4h at the refrigerant outlet of the cooling duct. In addition, in large-capacity transformers, the unit volume and calorific value is large, so
+ line end sO Because the heat transfer by natural convection is stupid and there is almost no cooling, there is a point *1 on the center line of cooling duct 1!4
The temperature distribution becomes 6O.

As described above, the highest temperature point of the winding occurs at the end face of the upper winding near the refrigerant outlet, and the temperature is considerably higher than the average temperature of the winding.

This invention is the ninth to solve the above-mentioned drawbacks,
An object of the present invention is to provide a foil-wound transformer that can even out the temperature distribution of the winding.

The present invention is a foil-wound transformer in which the number of cooling ducts can be reduced by providing a cooling duct and a single pipe inside the coil.

The present invention will be described in detail below with reference to the drawings.

FIG. 3 shows an embodiment of the foil-wound transformer according to the present invention.
It is a schematic diagram of the rr plane. The foil-like conductor 2 and the insulating sheet 3 are overlapped and wound to form a low-voltage side winding body and a high-voltage side winding body. A compact cooling duct 6 is built into these rolls. There is a thin gap inside this cooling duct 6, and Freon R-11
A refrigerant 14 such as 3 or FCT5 is completely discharged and circulated through the pump 7 so as to flow into the cooling duct from above, and the heat generated in the foil 11 is removed to a cold temperature of 14 K, and the heat is received. The cooling agent 14 is cooled by cooling water in the heat exchanger 8,
A circulation circuit is used in which cold intelligence is pumped into the typeface by a pump 7. The cooling duct 6 is made of metal such as stainless steel, and the oil guide pipe lO! An S-thin pipe 11 is used for the I-connection, and the cooling duct 6 is insulated from the ground potential of the oil guide pipe 10, tank top, etc. The potential of the cooling duct 6 is coupled to the same potential as the coiled foil conductor because it is wound within the coil. neat pipe 18
is installed between the opposing cooling ducts), and releases heat from the humid part at the bottom of the heat pipe and releases heat from the low temperature part at the top of the heat pipe. At this time, the temperature distribution of the heat pipe is as shown by the second VaO dot-dashed line 170, and the temperature difference between the upper and lower parts of the P part is averaged to a small value. By providing a heat pipe between each of the plurality of cooling ducts provided in this way, the number of cooling ducts can be reduced.

Next, other embodiments of the present invention will be shown. As shown in Fig. 4, extend the heat pipe up and down S, and extend the 9th part K 74
This is intended to further increase the cooling effect by attaching a 19 kniL b tube and dissipating heat to the insulating medium port to lower the temperature of the heat pipe. At present, 8F is mainly used as the insulating medium 13, but the cooling performance of the insulating medium 13 can be improved by adding substances such as 70N B-11 or Freon &-12 to this SF. Alternatively, the Oa degree may be lowered. Note that the insulating medium 13 in the tank 12 is not limited to gas, but may also be a liquid such as insulating oil without impairing the effects of the present invention.

4. A simple mf14 in direction 111 is a cross-sectional schematic diagram showing the general configuration of a conventional foil-wound transformer, Figure 2 is a temperature distribution diagram of the winding, and Figure 3 is a schematic configuration of an embodiment of the present invention. FIG. 4 is a schematic cross-sectional view showing another embodiment of the present invention.

2... Foil conductor, 3... Insulating sheet.

6... Cooling duct, 18... Heat pipe.

19...Radiating fin.

Daihorito Patent attorney Close aide 11 Yu (1 other person) Figure 1 Figure 2 Correct

Claims (1)

[Claims] A foil-wound transformer characterized in that a cooling duct and a heat pipe are built into a roll made by overlapping and winding a foil-like conductor and an insulating sheet.