JPS6223441B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of assembling a single-phase transformer for high voltage, which reduces the weight during transportation and reduces the size.

In recent years, with the increase in electricity demand, 500KV power transmission has been realized, and even higher voltage power transmission is planned in the near future. Since the bank capacity of such ultra-high voltage power transmission transformers is large, it is necessary to configure banks with single-phase transformers in Japan, where transportation such as railways and roads has severe limitations. Furthermore, as power transmission distances become longer, these transformers are often installed in mountainous areas where transportation conditions are even more severe, and it is desired to reduce the weight and size during transportation.

Figure 1 is a diagram showing the winding arrangement and connections inside this type of single-phase single-winding transformer, in which a tertiary winding 2A, a shunt winding 2B, and a series winding 2C are arranged around the iron core 1. There is. For example, an autotransformer with 500KV
When interconnecting with 275KV, connect to primary terminal 3.
Charge high voltages of 500KV and 275KV to secondary terminal 4, respectively. Then, an outlet 5 for the primary terminal 3 of the series winding 2C is drawn out from the center of the winding height in consideration of ground insulation, and an outlet 6 connected to the secondary terminal 4 is drawn out from above and below the winding 2C. Further, the outlet 7 of the shunt winding 2B connected to the secondary terminal 4 is drawn out from inside the series winding 2C.

In addition, due to restrictions on transportation dimensions due to high voltage and large capacity, especially limitations on transportation width, each of the above-mentioned windings 2A, 2
B and 2C are distributed and wound around multiple legs of the iron core to reduce the winding diameter and connect them in parallel or series.

Figure 2 is a schematic configuration diagram showing an example of such a transformer, in which two windings 2 are connected to two main legs of a single-phase four-leg iron core 1.
The windings 2 are divided into sets and wound in parallel with each other through internal leads 5 and 6. The iron core 1 is housed in a tank 8 and led out to the outside via primary and secondary terminals 3 and 4 provided in a primary duct 9 and a secondary duct 10 attached to the tank 8. However, in general, with this structure, the bank capacity is 1000 MVA and the transport weight of a single unit is approximately 150 tons.

When transportation limits and weight restrictions become more severe, a single-phase converter consisting of two units is used as shown in Figure 3. That is, two sets of tripod cores 1 are each wound with a winding 2, stored in separate tanks 8, and connected together via a connecting duct 11. However, in this type of iron core 1
Because the weight of the side legs increases, the transport weight for one unit is approximately 90 tons, which limits the amount of weight reduction possible. Furthermore, in this type of unit, since two units constitute a single-phase unit, extra space is created between each tank 8, increasing the installation area, and internal connections between the units are made by the connecting duct 11, so there is no connection. This increases the number of locations, which is undesirable from the standpoint of preventing moisture absorption inside the tank during on-site installation.

The present invention has been made in view of the above circumstances, and is a method for assembling a high-voltage single-phase transformer that can reduce transportation weight and dimensions, reduce on-site installation area, and improve reliability. The purpose is to provide the following.

An embodiment of the method of the present invention is shown below in Figures 1 to 3.
This will be described in detail with reference to a plan view shown in FIG. 4 and a cutaway front view shown in FIG. In the figure, reference numeral 1 denotes an iron core in which a winding 2 is appropriately divided and wound.For example, in the case of a four-leg iron core, the winding 2 is wound around two sets of main legs in the center. Then, as shown in the front view and plan view shown in FIGS. 6a and 6b, this core 1 is divided into parts 1A at the center of the upper and lower yokes between the main legs with a gap of a, and a laminated layer of length a is separated between the main legs. The core is punched out 1P for lap jointing. That is, in this lap joint portion, the core 1 and the core punched plate 1P are joined together with the lap dimension b to prevent deterioration of the core characteristics. A tank 8 corresponds to the divided portion 1A of the iron core 1.
is divided into left and right tanks 8A and 8B, and a flange is provided in the vertical direction. And left and right tanks 8
A connection tank 12 is provided between A and 8B and connected together by the flanges, and the high voltage internal leads 5 and 6 are connected to the primary and secondary terminals 3 and 4 to this connection tank 12. Ducts 9 and 10 are provided. In addition, during on-site installation, the winding 2
In order to prevent the water from absorbing moisture, the left and right tanks 8A,
A barrier 13 made of press board, rubber film, etc. is provided at the open end of 8B.

When transporting this transformer, tank 8
A, 8B are divided at the connection tank 12, and the iron core 1 is divided at the division 1A, and its weight is calculated.
Both volumes can be reduced to approximately 1/2. For example, the seventh
As shown in the figure, a cover 14 may be attached to the edge of the opening into which the tank 8 is divided and transported. In addition, when reassembling the tanks 8A and 8B that were transported separately in this way on-site, reassembling the divided part 1A of the iron core 1, connecting the internal leads 5 and 6, etc. will be performed on the left and right tanks 8A and 8B.
After the connection tank 12 is connected, the connection tank 12 is partitioned off from the winding 2 by a barrier 13.
It can be done inside. Therefore, it is possible to reliably prevent the winding 2 from absorbing moisture, and the connection tank 12
Moisture absorption can be minimized by blowing dry air during work inside. Further, the only insulating material in the connection tank 12 is the insulation of the internal leads 5 and 6, and moisture can be reliably removed by vacuuming and hot oil circulation after assembly, and the barrier 13 can then be removed. Also, primary
Since the secondary terminals 3 and 4 are provided on both sides of the connection tank 12, the high voltage internal leads 5 and 6 are led out from the winding 2 at a position that does not approach the inner wall of the tank 8 and are routed through the ducts 9 and 10. It can be connected easily and has extremely high insulation reliability.

It should be noted that the present invention is not limited to the above-mentioned embodiments. For example, if there is sufficient transport limit, the connecting tank 12 may be configured integrally with one of the tanks 8A, 8B, or if the transport limit is met. In severe cases, the number of legs of the iron core 1 may be increased and the number of divisions during transportation may be increased.

As described in detail above, the present invention stores an iron core divided into a plurality of parts at the yoke part between the plurality of main legs each wrapped with a winding wire into a plurality of tanks divided according to the number of divisions, and each tank is divided into two parts. The opening is sealed with a barrier through which the iron core end and the lead pass airtight, and a cover is attached and transported. During assembly, the cover is removed and the openings of each tank are connected by a connecting tank, and the inside of the connecting tank is sealed. In this process, the divided parts of the core are joined together via core punching, internal leads are connected, and then the barriers that seal the openings of each tank are removed. Therefore, the transportation weight and dimensions can be reduced, and the on-site installation area can also be reduced.
Furthermore, the windings are not exposed to the atmosphere during transportation or assembly, so there is no risk of moisture absorption.
It is possible to provide a method for assembling a single-phase transformer that does not cause deterioration of insulation properties and can improve reliability.

[Brief explanation of the drawing]

Figure 1 is a diagram showing the winding arrangement and connection of a single-phase autotransformer, Figures 2 and 3 are diagrams showing different conventional examples,
FIG. 4 is a plan view showing one embodiment of the present invention, FIG. 5 is a cutaway front view of the above embodiment, FIGS. FIG. 7 is a diagram showing the state of the above embodiment during transportation. 1... Iron core, 1A... Divided part, 1P... Iron core punched, 2... Winding, 3, 4... Terminal, 5, 6... Internal lead, 8A, 8B... Tank, 9, 10... …
Duct, 12...connection tank, 13...barrier.

Claims (1)

[Claims] 1 The core is divided into multiple parts at the yoke between multiple main legs each wrapped with a winding wire, and the core is divided into multiple tanks according to the number of divisions, and the opening of each tank is airtight between the core end and the lead It is sealed by a penetrating barrier and transported with a cover attached, and when assembled, the cover is removed and the openings of each tank are connected by a connecting tank, and the divided parts of the iron core are connected to each other in the connecting tank. A method for assembling a single-phase transformer, characterized in that the single-phase transformer is joined together via punched plates, internal leads are connected, and then a barrier sealing the opening of each tank is removed.