JPH02144905A - Static induction instrument - Google Patents

Abstract

PURPOSE:To increase cooling performance of a winding and restrict pressure rise in a tank for improving insulation reliability by providing a first cooling device for cooling at least one of an iron core and a winding with an insulating condensible refrigerant and a second cooling device for cooling the tank, the latter being disposed on the wall of the tank. CONSTITUTION:Windings 4, 5 housed in a container 11 of a first cooling device 12 are colled by a refrigerant 10 having excellent cooling capability. The refrigerant 10 absorbing heat is cooled by a cooler 14 provide externally, and circulated. Additionally, part of the refrigerant absorbing heat is evaporated in the tank and allowed to float in the tank 1 with an insulating medium 13. Herein, condensible evaporated gas is cooled by a second cooling device 17 by a second cooling device 17 provided on the external wall of the tank 1 into a liquid which is in turn stored in a residence section 18 at the bottom of the tank and fed to the cooler 14 through a supply tube 16 for circulation. Additionally, the windings 4, 5 are insulated by an insulating condensible refrigerant 10, and insulation between the windings 4, 5 and the tank 1 are preformed by noncondensible insulator 13 such as SF6 gas.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a stationary induction device that circulates a condensable cooling medium to insulate and cool a winding portion.

(Prior technology) In recent years, there has been an increasing need for static induction equipment such as transformers and reactors to have higher voltage and larger capacity, and in order to reduce the installation area, it is desirable to downsize and downsize the equipment. It is rare.

Generally speaking, in recent years, from the viewpoint of disaster prevention, insulating gases such as SF6 gas have been used as insulating media and cooling media in order to make equipment nonflammable. However, SF
Insulating gases such as 6 gases have the same or better insulating properties than insulating oil, but their specific heat and specific gravity are low, and their cooling properties are inferior.

Therefore, in large-capacity equipment, SF6 gas is forcibly circulated to cool the core, windings, etc., but as the gas flow rate increases, the head loss in the flow path also increases.
It is necessary to suppress the speed to about several m/sec. Therefore, there is a limit to the improvement of the cooling effect, and the cooling performance is generally several times lower than that of insulating oil.

Therefore, as a means to solve the above problems, a method is used in which SF6 gas and a nonflammable liquid with a boiling point of about 100°C or less are used together, insulation is performed mainly by SF6 gas, and cooling is mainly performed by the nonflammable liquid. There is something. This method involves spraying a non-flammable liquid (e.g. CFC) onto loss-generating parts such as iron cores and windings, and when it comes into contact with high-temperature loss-generating parts,
It uses the latent heat of vaporization to efficiently transport heat to the outside.

Figure 2 shows an example of such stationary guidance equipment.

That is, an iron core 3, an outer winding 4, and an inner winding 5 are housed in a transformer tank 1, and a nozzle 6 is arranged above them and on the side of the outer circumference. A pump 8 pumps the nonflammable liquid 9 stored at the bottom of the tank into the nozzle 6 via a pipe 7.
It is supplied to the iron core 3, windings 4, 5, etc., which are heating elements.

Further, the transformer tank 1 is connected to a heat exchanger 2 provided outside thereof. Then, the nonflammable liquid sprayed within the transformer tank 1 comes into contact with the high temperature part of the heating element and partially evaporates, at which time it absorbs heat from the high temperature part and cools it. Meanwhile, the steam enters the heat exchanger 2, where it transfers heat to the outside of the tank and returns to liquid. This liquid and the liquid that has flowed down without evaporating along the surface of the heating element returns to the bottom of the tank. In this way, the nonflammable liquid is continuously circulated by the pump 8 for cooling.

(Problems to be Solved by the Invention) However, in the conventional stationary guidance equipment having the configuration as described above, there were problems to be solved as described below.

In other words, the nonflammable liquid sprayed on the windings has condensability and vaporizes when the device is energized and the temperature rises, so the tank 1 is filled with the vaporized condensable liquid and the pressure inside the tank increases. This could lead to tank damage and explosion.

In addition, in general, condensable liquids have a property that it is difficult for the phase change from a vaporized state to a liquid state to occur when a non-condensable insulating gas such as SF6 gas is mixed, so the cooling performance is significantly reduced. decreases to Conventionally, in order to prevent such a decline in cooling efficiency, when the temperature inside the transformer rises and the tank is filled with vaporized condensable liquid, the transformer reaches a state where it can fully perform its absolute Rfa performance. A method has been used in which the non-condensable insulating gas is collected in a special container and separated, but this method has the disadvantage that the structure becomes very complicated.

The present invention was proposed to solve the above-mentioned drawbacks, and its purpose is to provide a stationary induction device with excellent winding cooling performance, suppressed pressure rise in the tank, and high insulation reliability. It is in.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a stationary induction device comprising an iron core and a winding housed in a tank, in which at least one of the iron core or the winding is made of a condensable material having an insulating property. A first cooling device is provided for storing the cooling medium in a container together with a cooling medium and circulating the cooling medium to a cooler provided outside the tank for cooling, and storing the container in a tank filled with a non-condensable insulating medium. Further, the tank is characterized in that a second cooling device for cooling the tank is provided on the wall of the tank.

(Function) According to the stationary induction device of the present invention, the core or the winding can be efficiently cooled by the insulating condensable cooling medium housed in the container, and the vaporized condensable gas can be cooled efficiently. Since it is cooled by the second cooling device provided on the tank wall, it is possible to suppress the pressure increase inside the tank.

(Example) Hereinafter, an example of the present invention will be specifically described based on FIG. Note that the same members as those of the conventional type shown in FIG. 2 are given the same reference numerals, and explanations thereof will be omitted.

In this embodiment, as shown in FIG.
A first cooling device 12 is formed by storing the windings consisting of the inner winding 5 and the inner winding 5 in a container 11 together with an insulating condensable cooling medium 10, and the first cooling device 12 and the iron core 3 are , SF6 gas, or other non-condensable insulating medium 13. Further, the first cooling device 1
The cooling medium 10 housed in the container 11 constituting the
A liquid pump 1 is connected to a cooler 14 provided outside the tank 1.
5 so that the liquid is circulated through a liquid sending pipe 16. Generally speaking, a second cooling device 17 for directly cooling the tank is attached to the outer wall of the tank 1, and is configured to cool the vaporized gas of the condensable liquid and the non-condensable insulating medium vaporized in the tank. It is configured. Furthermore, a retention section 18 is provided at the bottom of the tank 1 to store the cooling medium 10 that has liquefied and fallen within the tank, and is communicated with the upper liquid feeding pipe 16 . Note that as the condensable cooling medium, a nonflammable cooling medium such as perfluorocarbon is used.

In the stationary induction device of this embodiment having such a configuration, the windings 4 and 5 housed in the container 11 of the first cooling device 12 are cooled by the cooling medium 10 having an excellent cooling function. Moreover, the cooling medium 10 that has obtained heat is cooled by a cooler 14 provided outside and circulated. Also,
A portion of the cooling medium that has gained heat is vaporized within the tank and floats within the tank 1 together with the insulating medium 13. At this time, the condensable vaporized gas is cooled by the second cooling device 17 provided on the outer wall of the tank 1, becomes a liquid, is stored in the retention section 18 at the bottom of the tank, and is passed through the liquid supply pipe 16 to the cooler 1.
4 and circulated.

Further, the windings 4 and 5 are insulated by a condensable cooling medium 10 having insulation performance, while the insulation between the windings 4 and 5 and the tank 1 is performed by a non-condensable insulating medium 13 such as SF6 gas. be exposed.

As described above, according to this embodiment, since the cooling medium 10 is circulated, the cooling efficiency is high, and since the evaporated cooling medium is also recovered through the liquid sending pipe 16, the amount of cooling medium can be reduced. Furthermore, there is no need to replenish the cooling medium during operation, which simplifies maintenance work. In general, since less cooling medium 10 is needed, the weight and size of the transformer can be reduced, and the cost of the transformer can also be reduced.

Further, in the cooler 14 provided outside the tank 1, the heat exchange rate usually deteriorates when gas gets mixed in, but in this embodiment, the insulating medium 13 does not get mixed in, so the cooling characteristics do not deteriorate. . Roughly, the condensable gas vaporized in the tank 1 is transferred to a second cooling device 17 installed on the outer wall of the tank.
Since the tank is cooled by gas, pressure rise inside the tank due to vaporized gas can also be suppressed.

Furthermore, the windings 4, 5 are connected to the cooling medium 101. : Because it is immersed, the gas pressure inside tank 1 does not increase.
Maintenance protection devices such as conservators can be simplified.

It should be noted that the present invention is not limited to the embodiments described above, and it is possible to store either the windings 4, 5 or the iron core 3 together with the cooling medium in the container constituting the first cooling device. Both may be used, or each may be stored in separate containers. The container may be an integrally molded product made of reinforced plastic or the like, or may be a liquid-tight combination of an inner cylinder, an outer cylinder, and a bottom plate.

Further, the second cooling device 17 disposed on the outer wall of the tank can use a method such as forming a reinforcing rib on the tank outer wall into a hollow shape and flowing a refrigerant inside the rib, and the cooling method thereof is as follows. Air cooling, liquid cooling, blower type, etc. can be selected as appropriate. Roughly speaking, the condensable cooling medium is used as a non-flammable medium, and tank 1 is
If the insulating medium sealed inside is also a nonflammable insulating medium, the entire transformer becomes nonflammable.

[Effects of the Invention] As described above, according to the present invention, the first cooling device cools at least one of the iron core or the winding with an insulating condensable cooling medium, and the tank is mounted on the tank wall. By the trivial measure of providing a second cooling device for cooling,
Excellent winding cooling performance, suppressing pressure rise inside the tank,
A static induction separate device with high insulation reliability can be provided.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a stationary guidance device of the present invention, and FIG. 2 is a configuration diagram of a conventional stationary guidance device. DESCRIPTION OF SYMBOLS 1... Transformer tank, 2... Heat exchanger, 3... Iron core, 4... Outer winding, 5... Inner winding, 6... Nozzle, 7... Pipe, 8... Pump, 9... Nonflammable liquid, 10... Condensable cooling medium, 11... Container,
12... First cooling device, 13... Non-condensable insulating medium, 14... Cooler, 15... Liquid feeding pump, 16... Liquid feeding pipe, 17... Second Cooling device, 18... Retention part.

Claims (1)

[Claims] A stationary induction device comprising an iron core and a winding housed in a tank, wherein at least one of the iron core or the winding is housed in a container together with an insulating condensable cooling medium, and the cooling medium A first cooling device is provided for cooling the container by circulating it through a cooler provided outside the tank, the container is housed in the tank filled with a non-condensable insulating medium, and a wall of the tank is provided with:
A stationary induction device characterized by being provided with a second cooling device that cools a tank.