JPH0250405A - Oil filled electric apparatus - Google Patents

Abstract

PURPOSE:To decrease a chance of a sulfide corrosion phenomenon and to improve the insulating properties by storing a bare metal consisting of copper or silver in a spare tank and by letting the insulating oil in a main tank circulate in the spare tank. CONSTITUTION:A main body 2 constituted by coils wound around iron cores and insulating oil 3 are stored in a tank 1. With a rise in oil temperature, the insulating oil 3 in the tank 1 circulates in a spare tank 5 through pipes 4a and 4b. The insulating oil 3 contacts a bare metal 7 consisting of copper or silver in the spare tank 5 and on the surface of the bare metal, sulfide corrosion happens, resulting in the generation of a corrosion product such as copper sulfide and silver sulfide. By this method, a sulfidizing corrosion phenomenon generated on the surface of a bare conductor of the main body of an apparatus can be decreased, with the insulating properties improved.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to oil-filled electrical equipment such as transformers and reactors, and particularly relates to oil-filled electrical equipment such as transformers and reactors. The present invention relates to a device for reducing sulfide corrosion of bare conductors.

(Prior Art) In oil-filled electrical equipment such as transformers and reactors, in order to maintain insulation of the equipment, a tank housing the main body of the equipment, such as the iron core and windings, is filled with insulating oil. The windings that make up the main body of oil-filled electrical equipment are generally wrapped around an iron core with an insulation coating of a predetermined thickness around the bare conductor to strengthen the insulation of the winding itself. Direct contact with insulating oil is dangerous.

However, the lead wires that connect the windings to the lead bushings and the switching devices that switch voltage, current, etc. are not coated with insulation and are exposed as bare conductors that come into direct contact with the insulating oil. . Insulating oil used in oil-filled electrical equipment is generally composed of organic substances and contains main components such as gas, carbon, hydrogen, and oxygen, as well as many other components such as nitrogen and sulfur. These components do not react with metals and are known to exhibit stable performance over long periods of time.

(Problem to be Solved by the Invention) However, even with insulating oil having such characteristics, a small portion of the sulfur component that has an organic chemical structure may cause damage to the steel or chain constituting the bare conductor. There are metals that react with metals such as metals and cause sulfide corrosion, and substances with electrically good conductive properties such as sulfide steel and silver sulfide are generated on the surface of bare conductors. When such corrosion products are generated and accumulated on the surface of a bare conductor, an electric field may be concentrated in that area, leading to the possibility of corona discharge. In addition, such force corrosion products have a physically soft characteristic and may be peeled off from the surface of the bare conductor due to external factors such as vibration or oil flow, causing the insulating oil to float. In order to maintain the desired properties of electrical equipment, high insulating performance is required. If these corrosion products of good conductivity become suspended in the insulating oil, the insulating performance of the insulating oil will be significantly reduced. There is a high risk of serious accidents such as insulation breakdown of oil-filled electrical equipment.

The present invention has been made in view of the above points, and an object of the present invention is to reduce the sulfide corrosion phenomenon occurring on the bare conductor surface of the device body, and thereby obtain an oil-filled electrical device with improved insulation performance.

[Structure of the Invention (Means for Solving the Problem) In order to achieve the above-mentioned object, the present invention provides an auxiliary tank separate from the tank housing the main body of the device, and contains copper in the auxiliary tank. Alternatively, a bare metal whose main component is silver is stored, and the insulating oil in the tank is circulated into the auxiliary tank. Furthermore, measures are taken to ensure that the insulating oil flowing into the auxiliary tank comes into sufficient and positive contact with the bare metal.

(Function) By doing this, the insulating oil in the tank flows into the auxiliary tank, and when it circulates, sulfide corrosion is actively promoted on the surface of bare metal in this auxiliary tank, causing nitrification from the insulating oil. Components that cause corrosion are removed, greatly reducing sulfide corrosion phenomena in the main body of equipment inside the tank.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. 1 and 2, an equipment body 2 consisting of an iron core and a winding wound around the iron core is heated with insulating oil 3 in an IFi tank.
It is stored with. Mother eaves 4m and 4b are connected to the upper and lower parts of the tank 1, and an auxiliary tank 5 is provided so that the insulating oil 3 in the tank 1 flows through these a4, f4n, and ah. Valves 6* and 6b are attached to the I4 ear '4m*1b, respectively. Inside the auxiliary tank 5, there is provided a bare metal 2 whose main component is copper or silver, which is the same as the material used for the bare conductor of the main body of the device, as explained in detail in Figure I2. That is, the insulating oil 3 flowing from the tank 1 through the tubes 4m and 4b comes into contact with the bare metal 1 in the auxiliary tank 5. In order to sufficiently and actively promote this contact, the bare metal 2 is arranged in a row with a plurality of fins extending radially around the shaft 8.
A motor 9 is provided to rotate the auxiliary tank 5 within the auxiliary tank 5. The auxiliary tank 5 is also provided with an oil temperature regulator 10 for adjusting the temperature of the insulating oil in the auxiliary tank 5 and an inspection window 11 made of a transparent plate so that the condition inside the auxiliary tank 5 can be visually inspected. There is.

Furthermore, there is no place in the middle of the above-mentioned vias 4m and 4b.
Filters 12m and 12b for filtering the edge oil 3 are provided.

According to the oil-filled electrical equipment of the present invention configured as described above,
As the oil temperature rises, the insulating oil 3 in the tank 1 housing the device main body 2 is naturally circulated through the main tubes 4 & 4b into the auxiliary tank 5. As a result, it comes into contact with the bare metal 2 whose main component is copper or silver in the auxiliary tank 5 containing three insulating oils, and sulfide corrosion occurs on its surface, producing corrosion products such as copper sulfide and silver abrasion. As a result, the components contained in the insulating oil 3 that cause sulfide corrosion are reduced, and sulfide corrosion in the equipment body within the tank 1 is significantly reduced. Since no voltage is applied to the bare metal 7 in the auxiliary tank 5, even if corrosion products are generated on this surface, or if they float in the auxiliary tank 3, this will cause insulation problems. Never. Moreover, since the insulating oil returning from the auxiliary tank 5 to the tank 1 is filtered by the filter provided in the middle of the arm eve 4b, the insulating oil in the tank 1 is of good quality without any suspended matter. Auxiliary tank 5
Inside, in order to make sufficient contact between the insulating oil 3 and the bare metal 7, the shaft 8 to which the bare metal 2 is attached is rotated by the motor 9, or the oil temperature is changed by the oil temperature regulator.
Sulfide corrosion on the surface of bare metal 1 is accelerated. If it is desired to check the degree of sulfide corrosion acceleration in the auxiliary tank 5, an inspector can visually check through the inspection window 11, and if it is necessary to replace the filters 12m, 12b due to sulfide corrosion acceleration, the pulp 6a, 6b can be closed to facilitate replacement work.

In the above embodiments, the cooling system for oil-filled electrical equipment was not specifically explained, but if it is a natural circulation type cooling system, it may be placed in the middle of the piping, or if it is a forced circulation type cooling system, it may be cooled. The auxiliary tank of the present invention can be installed by branching from the vessel piping.

[Effects of the Invention] As described above, according to the present invention, there is provided an oil-filled electrical device in which a main body consisting of an iron core, a winding, and a bare conductor made of steel or a chain are housed in a tank together with insulating oil. A bare metal whose main component is the same as that of the bare conductor is stored in an auxiliary tank, and the insulating oil in the tank is circulated through this auxiliary tank so that it comes into contact with the bare metal, so that the main body of the device It is possible to reduce the sulfide corrosion phenomenon that occurs on the surface of bare conductors, thereby obtaining oil-filled electrical equipment with improved insulation performance.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing one embodiment of the present invention, and FIG. 2 is a perspective view of the main part thereof. 1...Tank, 2...Equipment body, 3...Insulating oil,
4 a. 4b... Eve, 5... Auxiliary tank, 2... Bare metal.

Claims (1)

[Claims] In oil-filled electrical equipment, which consists of a device body consisting of an iron core and windings, and a bare conductor made of copper or silver, housed in a tank together with insulating oil, a bare metal whose main component is the same as that of the bare conductor is placed in an auxiliary tank. 1. An oil-filled electrical device, characterized in that the insulating oil in the tank is circulated within the auxiliary tank and brought into contact with bare metal.