JPS61245508A - Method and apparatus for supplying insulating oil - Google Patents

Abstract

PURPOSE:To supply an insulating oil rapidly into an electric apparatus by a method wherein the inside of a joint connected to the apparatus is made vacuum and then filled up with the insulating oil, and thereby this insulating oil is supplied into the apparatus under pressure. CONSTITUTION:One connecting port of a T-shaped three way joint 2 is connected to an electric apparatus 1, and an oil storage tank 3 and a decompressing means such as a decompression vacuum pump 4 are connected to other connecting ports of the joint 2. Valves 5, 6 and 7 are fitted to the connecting portion of the electric apparatus 1 and the joint 2, that of the joint 2 and the tank 3 and that of the joint 2 and the pump 4 respectively so as to close and open passages. Moreover, a pressure applying means 8 is connected to the tank 3, and an insulating oil in the tank 3 is supplied to the electric apparatus 1 under the pressure from the means 8. After the inside of the joint 2 connected to the electric apparatus 1 is made vacuum by the decompressing means, the insulating oil in the tank 3 is filled up in the joint 2 and is supplied rapidly into the electric apparatus 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a supply method and apparatus for replenishing insulating oil to oil-filled electrical equipment such as a transformer.

[Technical background of the invention and its problems]

In oil-filled electrical equipment such as transformers, insulating oil is filled inside the equipment to insulate and cool the equipment. When such insulating oil undergoes oxidation and deterioration, it produces muddy substances and increases its viscosity, which impairs its cooling effect and insulation properties, so it is necessary to periodically sample and inspect the insulating oil.

However, when the amount of oil required for inspection is taken, the insulating oil inside the equipment decreases.1. Therefore, it is necessary to supply the insufficient amount of insulating oil each time, and the operation of the equipment must be stopped during this supply. No. In addition, during conventional oil extraction and refueling, air may get mixed into the insulating oil.
There are problems in that accurate test values cannot be obtained and the supplied insulating oil oxidizes early.

[Purpose of the invention]

The present invention has been made in consideration of the above-mentioned circumstances, and provides a method and apparatus that can supply insulating oil without stopping equipment, and that does not allow air to be mixed in when supplying or extracting insulating oil. is intended to provide.

[Summary of the invention]

To achieve the above object, the present invention connects a joint to an electrical device and connects an oil storage tank to the joint, and after creating a vacuum inside the joint, fills the joint with insulating oil. The insulating oil is then pressurized and supplied into the electrical equipment.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described in detail with reference to FIG.

FIG. 1 shows an example in which a transformer filled with insulating oil is used as an electrical device. One connection port of an rTJ-shaped three-way joint 2 is connected to the electrical equipment 1, and the three-way joint 2
An oil storage tank 3 and pressure reducing means such as a vacuum pump 4 are connected to the other two connection ports. Valves 5, 6, and 7 are attached to the connecting portions between the electrical equipment 1 and the joint 2, the connecting portion between the joint 2 and the oil storage tank 3, and the connecting portion between the joint 2 and the vacuum pump 4, respectively, to open the passages. It is designed to shut off and open.

New insulating oil is stored in the oil storage tank 3 connected via a valve 6, and a pressurizing means 8 is connected to this oil storage tank 3. This pressurizing means 8 includes a cylinder 8a filled with an inert gas such as nitrogen gas under pressure, and a supply pipe 8 connected to the cylinder 8a via a valve 8b.
The outlet portion of the supply pipe 8c communicates with the oil storage tank 3, and a pressurized bag 8d made of a flexible material such as rubber is attached to the outlet portion of the supply pipe 8c. When the valve 8b is opened and inert gas is supplied inside the pressurized bag 8d, the pressure expands in the oil storage tank 3, and the pressure is such that the insulating oil in the oil storage tank 3 is pumped in the direction of the electrical equipment 1. Add . Therefore, the pressurized gas is sealed in the pressurized bag and does not dissolve into the insulating oil in the oil storage tank 3, making it possible to supply highly pure insulating oil without gas contamination. Further, a vacuum bongo 4 is connected to the valve 7 attached to the other connection port of the joint 2 through a decompression passage 9.
is connected. This pressure reducing passage 9 has an oil level gauge 10. A valve 11 and a branch pipe 12 are installed in this order, and the vacuum pump 4 is connected to the left side of the branch pipe 12. Note that both 13a and 13b are pressure gauges.

Next, a method for supplying insulating oil from the oil storage tank 3 to the electrical equipment 1 will be explained using this embodiment as described above.

First, among the valves attached to each connection part of the joint,
While closing the valves 5 and 6, opening the valve 7 and further opening the valve 11 on the vacuum pump 4 side to open the depressurization passage,
The vacuum pump 4 is driven to create a vacuum inside the joint 2. At the time point 72 when a predetermined degree of vacuum is reached, the valve 11 is closed and the valve 6 on the oil storage tank side is opened. As a result, the insulating oil in the oil storage tank 3 fills the joint 2, where there is no air, and rises to the oil level gauge at the top of the valve 7. After visually checking that the oil level gauge is full of insulating oil, close the valve 7. close. Next, cylinder 8
The valve 8b on the a side is opened, pressurized gas is supplied into the pressurized bag 8d, and the insulating oil in the oil storage tank 3 is pressurized. Therefore, when the valve 5 on the electrical equipment 1 side is opened, insulating oil is supplied into the electric fan 1 through the joint by the pressure of the pressurized gas. As a result, the insufficient amount of insulating oil can be supplied without stopping the electrical equipment. In the above embodiment, the valve 5 on the electrical equipment side may be an electromagnetic valve, and a gas detector may be provided between the joint 2 and the valve 6. As a result, the pressure bag 8d
If the pressurized gas gets mixed into the insulating oil due to a rupture, the valve 5 can be closed to prevent the gas from getting into the electrical equipment.

FIG. 2 shows another embodiment of the invention, in which the same parts as in the previous embodiment are denoted by the same reference numerals. In this embodiment, a cross-shaped four-way joint is used as the joint 2,
An oil collection container 16 is attached to the added connection port via a valve 14 and a cock 15. In this embodiment, the extraction of insulating oil in the electrical equipment 1 and the replenishment of the insulating oil that is insufficient due to oil extraction are carried out continuously without gas being mixed in. The method will be explained below. .

First, the inside of the joint is evacuated as in the previous embodiment, but in this case, the valve 14. This is done with the cock 15 open. When a predetermined degree of vacuum is reached, open the valve 4 on the electrical equipment 1 side, fill the joint and oil sampling container 16 with insulating oil in the electrical equipment 1, and close the valve 11. Then, the valve 14 is closed, the oil sampling container 16 is removed from the valve 14 together with the cock 15, and the insulating oil is tested. Since air is prevented from entering the oil during oil sampling, accurate analysis can be performed. Next, after oil extraction, the insufficient amount of insulating oil is supplied from the oil storage tank 3, but this can be done in the same manner as in the previous embodiment.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to quickly supply insulating oil to electrical equipment, so there is no need to stop the electrical equipment, and even during the supply, gas may be mixed into the insulating oil. There's nothing to do.

[Brief explanation of the drawing]

FIG. 1 is a side view of one embodiment of the invention, and FIG. 2 is a side view of another embodiment. 1 Electrical equipment, 2 Couplings, 3 Oil storage tank, 4 Vacuum pump (pressure reducing means), 5.6, 7, 1.4 Valve, 8 Pressurizing means / Morning

Claims (2)

[Claims] (1) Lubrication of insulating oil characterized by evacuating the inside of a joint connected to an electric device, filling the inside of the joint with insulating oil, pressurizing this insulating oil, and supplying it to the inside of the electric device. Method. (2) A joint connected to an electrical device, an oil storage tank connected to the joint, a pressure reducing means connected to the joint to create a vacuum inside the joint, a valve disposed at each of the connection parts, and an oil storage tank. An insulating oil supply device comprising a pressurizing means for pressurizing and supplying insulating oil into electrical equipment.