JPH0669054A - Assembly method of single-phase transformer - Google Patents

Abstract

PURPOSE:To limit the reassembly of the transformer on the spot to the assembly of a bushing pocket and each unit transformer tank and to the connection of a high- voltage lead to a winding by a method wherein the high-voltage lead is transported in a regular state except that its connection to the winding is detached. CONSTITUTION:When a high-voltage lead 3 is transported, it is transported in a state that a multiple insulating barrier 3a has been assembled regularly except that it is separated from a winding lead 2a. A transportation cover 11 is attached to a part protruding from a high-voltage bushing pocket 5 at the high-voltage lead 3 after the part has been sealed airtightly by attaching an airtight film 10 to a pocket end part. An opening part in a connecting duct 8 for a unit transformer 1A connected to the high-voltage bushing pocket 5 is sealed in advance with a bag-shaped film 10 capable of housing a part in which the high-voltage lead 3 protrudes to the inside of a tank before the delivery of the transformer form a factory, and it is removed after the assembly operation of the high-voltage bushing pocket 5 and unit transformers 7A, 7B on the spot. Thereby, it is possible to prevent that the transformer absorbs humidity and that foreign bodies creep into the transformer, and it is possible to ensure the assembly quality in the factory of the insulation of the lead as it is.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for assembling a single-phase transformer, and more particularly to a method for assembling a single-phase transformer connecting two unit transformers arranged in parallel with each other and a high voltage bushing pocket.

[0002]

2. Description of the Related Art In recent years, with the increase in power demand, there is a tendency to increase the transmission voltage for efficient power transmission.
UHV power transmission of 000kV class is planned. As for the transformer, compared with the conventional maximum 500kV class transformer,
Both the voltage and the capacity will be doubled, which requires a breakthrough. In addition, since the location conditions of the substation where this UHV class transformer is installed are many in mountainous areas, various transportation restrictions will occur. Therefore, there are more transportation restrictions than the current 500kV transmission substation. Is expected.

Therefore, it becomes impossible to construct a three-phase transformer with three single-phase transformers as in the conventional 500 kV transformer, and it is necessary to further configure the single-phase transformer with two unit transformers.

A single-phase transformer composed of such unit transformers will be described with reference to FIG. Each unit transformer 1A, 1B constituting a single-phase transformer comprises an iron core 6 arranged in tanks 7A, 7B and a winding 2 wound around a main leg of the iron core 6.
Consists of The high-voltage lead 3 that connects the unit transformers 1A and 1B in parallel is connected to the bushing 4 in the high-voltage bushing pocket 5 at the end of the high-voltage line disposed between the tank surfaces where the unit transformers 1A and 1B face each other. . Where UH
In the case of a V transformer, the potential of the high voltage lead 3 is about 1000 kV
Becomes

[0005]

The high voltage lead of a UHV transformer is 2 times higher than the conventional maximum voltage of 500 kV lead.
Since the voltage is doubled, a configuration is adopted in which it is connected to the high voltage bushing 4 at the end of the high voltage line at the shortest distance by penetrating the tank facing surface from the center of the winding height. On the other hand, the high-voltage bushing pocket 5 has a unit transformer 1 because of transportation restrictions.
It is necessary to disassemble the tanks 7A and 7B of A and 1B and reassemble them on site.

Therefore, the assembly of the high pressure bushing pocket 5 and the tanks 7A and 7B and the high voltage lead 3 are carried out locally.
The reliability of UHV transformers depends on how much the connection and insulation work can be omitted, and the absorption of a large amount of insulation used in the high voltage bushing pocket 5 and each unit transformer 1A, 1B in the field assembly work and the prevention of foreign matter from entering. Will be the most important issue in ensuring security.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is to facilitate the assembly of a 1000 kV high voltage bushing pocket and two unit transformers in a UHV transformer. A single-phase transformer that can improve the reliability of on-site transformer assembly by minimizing the on-site assembly such as high-voltage lead connection and insulation work, and implementing moisture-proof and dust-proof measures during reassembly work. It is to provide a method of assembling a container.

[0008]

In order to achieve the above object, according to the present invention, two unit transformers connected in parallel are arranged such that the long sides of the tanks face each other, and the two unit transformers are connected in parallel. In a method for assembling a single-phase transformer in which a high-voltage line end bushing to be connected is arranged between the long sides of a tank, (1) the high-voltage lead and its insulating barrier are transported while being assembled in a bushing pocket, and the bushing pocket and the transformer tank. (2) After assembling one unit transformer and high-voltage bushing pocket, and then arranging the other unit transformer on the foundation. A method of connecting to the other connection port of the high-pressure bushing pocket by moving while being supported by a moving device and a jack, (3) the preceding paragraph (2)
In, in order to move the other unit transformer of the pre-assembled unit transformer and high-voltage bushing, the method of moving the other unit transformer by jacking it up to the same level as the level lifted from the foundation surface, (4)
A method of simultaneously removing the high-voltage bushing pocket and two unit transformers on a foundation by jacking and fixing them, then removing the airtight film, and connecting and insulating the high-voltage lead and the winding. is there.

[0009]

According to the method for assembling the single-phase transformer of the present invention, the high-voltage leads are transported in a normally assembled state except that the connection with the winding is disconnected, so that the on-site reassembly is performed in the bushing pocket and each unit transformer tank. It is possible to limit only to the assembling with and the connection between the high voltage lead and the winding. Also, during on-site assembly work, the high-voltage lead protruding from the high-voltage bushing pocket, the insulating barrier, and the opening of the unit transformer tank are sealed with an airtight film to ensure moisture absorption of the contents during operation and contamination of foreign matter from the outside. It can be prevented. Furthermore, after assembling one unit transformer tank and the high-voltage bushing pocket, the other unit transformer tank can be moved with a certain size lifted from the foundation surface by the moving device and jack, which facilitates on-site assembly. Can be done.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. Figure 1 shows two unit transformers connected in parallel and 1000k
It is a side view which shows a connection with a V high pressure bushing. As shown in the figure, each unit transformer 1A, which constitutes a single-phase transformer,
1B is composed of an iron core 6 arranged in tanks 7A and 7B and a winding 2 wound around a main leg of the iron core 6.

A high-voltage bushing pocket 5 on the high-voltage line end side is arranged between the tank surfaces where the unit transformers 1A and 1B face each other, and the high-voltage lead 3 connecting the unit transformers 1A and 1B in parallel is It is connected to the bushing 4 in the high pressure bushing pocket 5. In addition, each unit transformer 1A,
The winding 2 of 1B and the high-voltage bushing 4 are connected by the high-voltage lead 3 through the tank connection duct 8 at the winding height where the high-voltage line end is arranged or near the center. The high-voltage lead 3 is insulated by multiple insulating barriers 3a, and both ends of this high-voltage lead 3 are the unit transformers 1A and 1B, respectively.
The insulation of the connection portion is facilitated by approaching the winding lead-out 2a.

As shown in FIG. 2, the high-voltage lead 3 for transportation is a multiple insulating barrier 3 except that it is separated from the winding outlet 2a.
Transport a as it is normally assembled. The portion of the high-voltage lead 3 protruding from the high-pressure bushing pocket 5 is transported after the air-tight film 10 is attached to the pocket end and air-tightly sealed, and the transportation cover 11 is attached and protected.

Unit transformers 1A, 1B and 10 in the field
Figure 3 shows the process of assembly with the 00kV high-voltage bushing pocket 5.
Is shown in. That is, the opening of the connection duct 8 of the unit transformer 1A connected to the high-voltage bushing pocket 5 is sealed in advance with a bag-shaped film 10 capable of accommodating the portion where the high-voltage lead 3 projects inside the tank 7A before factory shipment. , The local high voltage bushing pocket 5 and the unit transformer tanks 7A and 7B will be removed after assembly work.

Next, a method of assembling the high pressure bushing pocket 5 and the unit transformer tanks 7A and 7B will be described with reference to FIGS. That is, after setting one transformer tank 7B at a regular position on the base surface 16, the high pressure bushing pocket 5 is lifted and assembled by a recker car. Next, the other transformer tank 7A is set near the regular position, and then the transformer tank 7A is supported by the front-rear direction moving position 13, the left-right sliding device 14, and the jack 15.

The transformer tank 7A is lifted to a level S which can be moved from the foundation surface, and is adjusted to the front, rear, left and right, and up and down, so that one side of the high pressure bushing pocket 5 is already assembled.
Connect with. At this time, the transformer 1B and the high voltage bushing pocket 5 have the same level S as the transformer 1A due to the jack 15.
It is lifted up to the base surface 16 at the same time after assembly with the transformer 1A.
Lower and fix.

Next, the operation of this embodiment will be described.
1000kV arranged between two unit transformers 1A and 1B
Since the high voltage bushing 4 and the winding 2 are connected in the vicinity of the winding outlet 2a and the high voltage lead 3 is extended to the surface of the winding 2, the connection is shielded by the winding surface of the same potential, and the insulation structure and the field Assembly work is greatly simplified.

The high-voltage bushing 4 and the high-voltage lead 3 are assembled with a plurality of insulating barriers 3a around them, and are housed in a high-voltage bushing pocket 5 while being sealed at both ends with an airtight film 10 as shown in FIG. Since the cover 11 is attached and transported, multiple insulation barriers 3a are available locally.
Since there is no assembling work and the contents are not exposed, moisture absorption and foreign matter mixture are prevented, and it becomes possible to secure the factory assembly quality regarding lead insulation as it is.

On-site assembly work of the unit transformers 1A, 1B and the high-voltage bushing pocket 5 is performed by connecting the end of the high-voltage bushing pocket 5 and the connecting duct 8 of the transformer tank as shown in FIG.
The film 10 attached to the part prevents moisture absorption of the inside insulator and mixing of foreign matter, thereby ensuring insulation quality.

On the other hand, although the transport weight of the unit transformers 1A and 1B is about 200 tons, the movement and centering for connecting with the high-voltage bushing 4 is before and after setting on the foundation surface 16,
Since the moving device 13 capable of adjusting the movement in the left-right and up-down directions, the slide device 14, and the jack 15 are combined,
Even when the high-voltage lead 3 projects from the end of the high-voltage bushing pocket 5, it can be carried out accurately and easily.

As described above, by adopting the method of assembling the unit transformers 1A, 1B and the high voltage bushing pocket 5 in the field, the connection work of the high voltage lead 3 is limited to only the winding lead-out portion 2a and the above-mentioned moisture proofing is performed. By taking dust-proof measures, it becomes possible to secure the insulation reliability of the most important high voltage lead of the UHV transformer.

Further, a centering guide is attached to a connecting bushing portion or the like in order to improve the assembly accuracy of the transformer tanks 7A and 7B and the high pressure bushing pocket 5 and to facilitate the work.

[0022]

As explained above, according to the transformer assembling method of the present invention, the disassembling portion is minimized because the disassembling and transporting is performed only at the 1000 kV high-voltage energizing portion of the UHV transformer and reassembling at the site. And complete moisture and dust proofing measures or shortening the on-site assembly period can be achieved. Therefore, the reliability of the on-site assembly quality of the UHV transformer can be ensured.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing a method of transporting the high pressure bushing and the lead shown in FIG.

FIG. 3 is a diagram showing measures to prevent moisture and dust in the contents during the assembly of the high voltage bushing pocket and the unit transformer.

FIG. 4 is a diagram showing a state during assembly of FIG. 3;

FIG. 5 is a diagram showing the final assembly stage of FIG. 3;

FIG. 6 is a configuration diagram of a conventional single-phase transformer including two unit transformers and a line end bushing.

[Explanation of symbols]

1A, 1B ... Unit transformer, 2, 2a ... High voltage winding, lead, 3,3a ... High voltage lead, Insulation barrier, 4 ... High voltage bushing, 5 ... High voltage bushing pocket, 6 ... Iron core, 7
A, 7B ... Transformer tank, 8 ... Connection duct, 10 ... Airtight film, 11 ... Transport cover, 12 ... Clean room, 13 ... Moving device, 14 ... Sliding device, 15 ... Jack, 16 ... Foundation.

Claims (1)

[Claims] 1. A unit transformer in which two unit transformers connected in parallel are arranged such that the long sides of the tank face each other, and a high-voltage line end bushing connecting the two unit transformers in parallel is arranged between the long sides of the tank. A method for assembling a single-phase transformer, characterized by including at least the following methods (1), (2), (3), and (4) in a phase transformer. (1) A method in which a high-voltage lead and its insulating barrier are assembled and transported in a bushing pocket, and the bushing pocket and the connection opening of a transformer tank are sealed with an airtight film and then a transportation cover is attached. (2) After assembling one unit transformer and the high voltage bushing pocket, the other unit transformer is connected to the other connection port of the high voltage bushing by being moved while being supported by a moving device and a jack arranged on the foundation. how to. (3) In the preceding paragraph (2), the preassembled unit transformer and high-voltage bushing pocket are jacked up to the same height as the level raised from the foundation surface to move the other unit transformer, and then the other unit transformer. How to move and connect. (4) A method in which a high-voltage bushing pocket and two unit transformers are simultaneously lowered onto a foundation by jacks and fixed, and then the airtight film is removed, and the high-voltage leads and windings are connected and insulated.