JP3614144B2 - Transformer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transformer that is frequently used in a power receiving / transforming facility.
[0002]
[Prior art]
As is well known, the oil-filled transformer of the power receiving / transforming equipment immerses the iron core around which the primary wire and secondary wire are wound in the insulating oil in the tank, and ends the primary wire and secondary wire. Is connected to the end of the penetrating conductor of the insulating penetrating bushing having an external connection terminal disposed on the tank surface.
[0003]
In addition, in order to connect an electrical device such as a switch installed on the primary side and the secondary side respectively with a transformer, a bus duct made of a conductor covered with a power cable or a ground metal jacket is used. Electric power cables and bus ducts with a capacity that takes into account the short-time withstand current of the power supply system electrically and mechanically are used. The connection terminal part of the transformer and switch is subjected to sufficient insulation terminal processing.
[0004]
[Problems to be solved by the invention]
In the prior art, the transformer and the electrical equipment installed on the primary and secondary sides are connected by power cables and bus ducts, which require large-capacity power cables and bus ducts. There is a problem in that sufficient insulation terminal processing must be performed in the transformer primary terminal section, and a lot of man-hours are required for the on-site adjustment work.
An object of the present invention is to provide a transformer that does not require equipment such as a power cable or a bus duct and can significantly reduce the number of on-site installation steps.
[0005]
[Means for Solving the Problems]
A feature of the present invention is that a cable is disposed through an insulating bushing soot penetrating through an upper plate of a tank sealed with an insulating material, and the lower end of the cable is lower than the lower end of the insulating bushing soot pipe. The lead wire of the primary wire ring is connected to the lower end located in the insulating material of the cable.
[0006]
In the present invention, the field construction work can be completed simply by connecting the power cable attached to the transformer to other equipment. Therefore, the connection equipment with other equipment such as a bus duct, the construction in the field, and the bushing terminal on the transformer surface No intermediate insulation work is required, and the on-site work process can be greatly shortened.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 and 2 show an embodiment of the present invention. FIG. 2 is a left side view of FIG. FIG. 1 shows an example of an oil-filled transformer.
[0008]
In FIG. 1, an insulating oil 5 as an insulating material is hermetically sealed inside a tank 1. The iron core 2 is configured by laminating silicon steel plates through which magnetic flux easily passes, and a primary wire ring 3 and a secondary wire ring 4 are wound in each phase (u, v, w phases in FIG. 2). The iron core 2 is soaked in an insulating oil 5.
[0009]
An insulating bushing soot tube 7 is fixed to the upper plate 20 of the tank 1 by a fixing metal 12. A cable 8 is disposed through the insulating bushing soot 7. FIG. 1 shows only one phase of the insulating bushing soot tube 7. A plug 22 connected to the switch terminal 15 is provided at the upper end of the cable 8 outside the tank 1. Further, the transformer secondary terminal 14 is fixed to the upper plate 20 of the tank 1 by a fixing bracket 21.
[0010]
FIG. 3 shows a detailed enlarged view of the insulating bushing soot tube 7.
In FIG. 3, an insulating bushing pipe 7 is fixed to the upper plate 20 of the tank 1 by a fixing metal 12. A cable 8 is disposed through the insulating bushing soot 7. The cable 8 is disposed such that its lower end 8 a protrudes downward from the lower end of the insulating bushing soot tube 7 and is located in the insulating oil 5.
[0011]
An O-ring 9-1 is provided on the inner wall of the upper end of the insulating bushing soot pipe 7 (outside of the tank 1), and is in close contact with the jacket of the cable 8. Further, an insulator 10-1 is filled between the O-ring 9 and the cable 8 on the outer side of the insulating bushing soot tube 7, and the surface of the insulating bushing soot tube 7 and the cable 8 is heat-shrink material (heat shrinkable material) 11-1. This prevents the ingress of moisture from the outside. These O-ring 9-1, insulator 10-1, and heat shrink material 11-1 constitute a sealing member.
[0012]
Similarly, an O-ring 9-2 is provided on the inner wall at the lower end of the insulating bushing soot pipe 7 (inside the tank 1) and is in close contact with the jacket of the cable 8. Further, an insulator 10-2 is filled between the O-ring 9 and the cable 8 on the outside of the insulating bushing soot tube 7, and the surface of the insulating bushing soot tube 7 and the cable 8 is heat-shrinked (heat shrinkable material) 11-2. To prevent the insulating oil 5 from seeping out from the tank 1. These O-ring 9-2, insulator 10-2, and heat shrink material 11-2 also constitute a sealing member.
[0013]
An electric field relaxation material 13 is inserted into the end of the cable 8 at the lower end of the insulating bushing soot tube 7 so that the electric field at the end of the cable 8 can be relaxed to shorten the terminal processing dimension.
[0014]
In this configuration, the switch terminal 15, which is an electrical device on the primary side, receives a high voltage directly from the inside of the tank 1, which has excellent dielectric strength, from the inside of the tank 1 by the cable 8 penetrating into the insulating bushing soot 7. Can be pulled out and connected directly. Therefore, it is possible to eliminate the need for air-insulated terminal processing work for high-voltage power cables at the primary terminal of the transformer, and the primary side of the transformer is electrically and mechanically commensurate with the short-term capacity of the system. Capacity cables and bus ducts are no longer necessary, and there is no need for production costs, local installation and adjustment work, and the number of local man-hours can be greatly reduced.
[0015]
FIG. 4 shows another embodiment of the present invention. The embodiment of FIG. 4 differs from the embodiment of FIG. 1 in that nitrogen gas 16 having high dielectric strength is sealed between the insulating oil 5 in the tank 1 and the tank 1 and sealed, and nitrogen gas is sealed in the upper portion of the tank 1. That is, the lead wire 6 of the primary wire ring 3 and the power cable 8 are connected at the portion.
[0016]
In the embodiment of FIG. 4 as well, it is possible to eliminate the need for air-insulated terminal processing work for the high-voltage power cable at the primary side terminal of the transformer, and the primary side of the transformer is electrically connected to the short-term capacity of the system.・ Power cables and bus ducts with a mechanically suitable capacity are not required, and production costs and installation and adjustment work are not required at all, which makes it possible to significantly reduce local man-hours. In addition, by connecting the lead wire 6 of the primary wire ring 3 and the power cable 8 with the nitrogen gas part 16, the terminal processing of the connection part can be simplified.
[0017]
As described above, according to the present invention, the cable is disposed through the insulating bushing pipe provided through the upper plate of the tank hermetically sealed with the insulating substance, and the lower end of the cable is lower than the lower end of the insulating bushing pipe. The lead wire of the primary wire ring is connected to the lower end located in the insulating material of the cable.
[0018]
Therefore, the field construction work can be completed simply by connecting the power cable attached to the transformer to other equipment. Insulation processing work is not required at all, and the field work process can be greatly shortened.
[0019]
In the above-described embodiment, the insulating material sealed in the tank is insulating oil, but it goes without saying that the same effect can be obtained even in a transformer in which an insulating gas such as SF6 gas is sealed.
[0020]
Further, it is obvious that high-pressure dry air may be sealed instead of nitrogen gas in which insulating oil and nitrogen gas are sealed in a tank.
[0021]
Furthermore, although the above-described embodiment is provided with a cable penetrating the insulating bushing soot only on the primary side, it is obvious that it may also be provided on the secondary side.
[0022]
【The invention's effect】
Therefore, according to the present invention, the field construction work can be completed simply by connecting the power cable attached to the transformer to other equipment. No need for air insulation treatment work at the terminal part, and the on-site work process can be greatly shortened.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an embodiment of the present invention.
FIG. 2 is a left side view of FIG. 1;
FIG. 3 is a detailed configuration diagram of a main part of the present invention.
FIG. 4 is a block diagram showing another embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Oil-filled transformer tank, 2 ... Transformer iron core, 3 ... Primary wire ring, 4 ... Secondary wire wheel, 5 ... Insulating oil, 6 ... Primary wire ring terminal lead wire, 7 ... Insulating bushing pipe, 8 ... Cable, 9 ... O-ring, 10 ... insulator, 11 ... heat shrink material, 12, 21 ... fixing bracket, 13 ... electric field relaxation material, 14 ... transformer secondary terminal, 15 ... switch terminal, 16 ... nitrogen gas, 20 ... Upper plate of tank 1, 22 ... Plug.

Claims (6)

In an insulating material hermetically sealed in the tank, in a transformer in which an iron core around which a primary wire ring and a secondary wire ring are wound is disposed, an insulating bushing soot penetrating the upper plate of the tank and fixed to the tank; A cable that is disposed through the insulating bushing soot and has a lower end protruding below the lower end of the insulating bushing soot and is located in the insulating material, and a hermetic seal that seals the upper and lower ends of the insulating bushing soot And a lead wire of the primary wire ring is connected to a lower end located in the insulating material of the cable. In a transformer in which an insulating oil and an insulating gas are hermetically sealed in a tank, and an iron core in which a primary wire ring and a secondary wire ring are wound is disposed in the insulating oil, the tank penetrates the upper plate of the tank and An insulating bushing soot pipe fixed to a tank, a cable disposed through the inside of the insulating bushing soot pipe and having a lower end protruding below the lower end of the insulating bushing soot pipe and located in the insulating gas, and the insulating bushing soot pipe A transformer comprising: a sealing member that seals an upper end portion and a lower end portion of the cable, wherein a lead wire of the primary wire ring is connected to a lower end located in the insulating gas of the cable. The transformer according to claim 1, wherein the insulating material is insulating oil. 2. The transformer according to claim 1, wherein the insulating material is SF6 gas. The transformer according to claim 2, wherein the insulating gas is nitrogen gas. 3. The transformer according to claim 2, wherein the insulating gas is high-pressure dry air.

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