JPS596490B2 - large capacity transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a large-capacity transformer, in particular an ultra-ultra-high voltage transformer, which can be transported within limited railway transportation limits and easily assembled on-site. Generally, when transporting large transformers, Surpel type freight cars are used.

FIG. 1 shows a cross section of a transformer transported by such railway transport, and the transport limit 1 in the direction of travel of the freight car is restricted by tunnels, platforms, etc. as shown by the dashed line. Therefore, a reinforcing beam 3 is provided for the tank 2, and the reinforcing beam 3 provides transportation strength, vacuum strength, and internal pressure strength.The cover 4 has the above-mentioned strengths within the transportation limit 1. If it can be held, use it as is, but if it cannot be held and the item is being transported beyond the transport limit, use a temporary lid that simply maintains airtightness from the outside air during transport. Around the iron core leg 5,
A tertiary winding 6, a secondary winding T) and a primary winding 8 are wound concentrically. As the transformer capacity increases, the winding outer diameter φ also increases, making it difficult to maintain a gap g between the winding and the tank 2. In this case, as shown in Figure 2,
In an ultra-ultra high voltage transformer such as 500 kV, a high voltage winding 11 is used with a high voltage primary line terminal 15 in the center and neutral point side terminals 14 arranged above and below it, as shown in the wiring diagram. A protrusion IT is provided in the center of the tank 2, which has an allowance for the width of the transport limit 1 shown by the dashed line in A, to ensure the insulation dimension required for insulation.

Note that 12 is a low voltage winding. However, if the transformer has a larger capacity or a higher voltage such as 1000kV, even with this structure, it will be impossible to maintain the insulation dimensions between the windings and the tank, and it will be difficult to assemble and transport the transformer. teeth,
It is necessary to use a system in which the entire upper part of the tank is used as a transport tank and this tank is replaced on-site. In such a method,
The transport tank is attached to the lower support stand that carries the contents of the transformer, and the main tank is attached directly to the lower support stand at the site, and the transport cover is then removed.

However, these methods require that the mounting surface of the lower support stand (lower tank) to the main tank be located outside of the mounting surface of the transportation tank. This part is restricted by the platform during transportation, and if there is such a protruding part, the width of the transport tank must be narrowed, which reduces the winding outer diameter φ by that amount. There is a need.
This mounting surface receives the contents load applied to the lower support body (lower tank) with bolts, etc., so the fact that this mounting surface is double for the transportation tank and the main tank means that the outer diameter of the winding is There are drawbacks that limit it. SUMMARY OF THE INVENTION An object of the present invention is to provide a large-capacity transformer that can be easily assembled at the installation site by transporting a transformer with a large winding diameter while minimizing the constraints imposed by the transportation tank platform. be. The present invention provides a method for forming a tank from at least an upper tank and a dish-shaped lower tank, and when forming a large-capacity transformer by arranging the contents of a transformer consisting of an iron core, windings, etc. in this tank, the tank is A flat plate fixing part to which a transport tank can be detachably attached is provided, and a vertical frame protruding from the bottom of this part is provided, and a lower tank expansion member with reinforcing beams is attached to this vertical frame at the installation site after being removed during transport. The upper tank is fixed to the lower tank expanding member. An embodiment of the large capacity transformer of the present invention will be described below with reference to FIG.

Around the core leg 5, a tertiary winding 6, a secondary winding 7,
Windings are wound concentrically in the order of the primary winding 8, and the upper and lower ends of these windings are connected to an upper fastener 20, a lower fastener 21,
It is fixed via a clamp bolt 9 and a support insulator 10. Further, the upper fastener 20 has an iron core sandwiched between connecting fittings 23. The entire transformer contents 28, such as the stiff iron core and windings, are installed and fixed on the lower tank 16 formed in a dish shape via the lower connecting fittings 23. 16A is a reinforcing metal fitting fixed to the lower surface of the dish-shaped lower tank 16 in order to reinforce it.

In addition, the lower tank 16 has a size that has the minimum gap G necessary for inserting the transformer contents 28 such as windings, and a size that is within the transport limit 1, as indicated by the chain double-dashed line. A flat plate fixing part 27 is provided to which the transport tank 19 shown can be detachably fixed. A lower tank enlarged part 18 reinforced with reinforcing beams 29 is fixed to a vertical frame 27A protruding from the lower part of the flat plate fixing part 27, and a lower main tank, which is a component of the upper tank, is fixed to the lower tank enlarged part 18. 13. The middle four tanks 24 and the upper main tank 25 are installed. The lower tank enlarged portion 18 provided with the reinforcing beam 29 is provided with a flap so that it is attached at the time of factory assembly, removed at the time of transportation, and fixed at the time of on-site assembly.

Therefore, when the lower tank enlarging member 18 is installed, it will have a shape that protrudes outward from the transport limit 1, but this will not cause any problem as it will be fixed at the installation site. When transporting, the contents 28 of the transformer are covered with a transport tank 19 shown by the two-dotted chain line, and the transport tank 19 is fixed to the plate-shaped fixing part 27 of the dish-shaped lower tank 16 with bolts 26. Carry out transportation.

After arriving at the site, the transformer is placed on the installation foundation, and the lower tank expansion member 18 is fixed to the vertical frame 27A by means such as welding. This lower tank expansion member 18
A lower main tank 13 is interposed on top with a packing 22 and is airtightly fixed by a welded portion 20. Therefore, on-site assembly work is also facilitated. Next, replace the middle main body tank 24 with the lower main body tank 13.
After assembling the top, the transport tank 19 is removed. Note that, since the reinforcing beams of the transport tank 19 protrude outward by a large amount, the method of attaching and then removing the lower body tank 13 and the middle body tank 24 results in an increase in the amount of oil. Also,
Depending on the location and time of transportation, care must be taken because if the outer surface of the transportation tank is not thoroughly cleaned in advance, there may be problems such as the oil poured into the main tank becoming dirty. In addition, to prevent the windings from absorbing moisture during transportation, a separate transportation tank 19 is installed.
Moisture-proofing can be achieved by covering the tank with an airtight bag (not shown) made of plastic sheet or the like at the factory before installing the tank, filling it with desiccant if necessary, and removing it when installing the tank after arriving at the site. can. As described above, the large-capacity transformer of the present invention minimizes the restrictions imposed by the transportation tank platform, and allows transformers with large winding diameters to be assembled and transported, This has the effect of making it possible to easily install the transformer on-site.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of a part of a conventional transformer during transportation, Figure 2 (a) is a cross-sectional view of a part of a conventional ultra-ultra high voltage transformer during transport, and the opening is a wiring diagram of the transformer. FIG. 3 is a partial sectional view showing the state of one embodiment of the large-capacity transformer of the present invention during transportation and on-site installation. 1...Transportation limit, 5...Iron core leg, 6.
...Tertiary winding, 7...Secondary winding, 8...
...Primary winding, 13...Lower main tank, 16
...Lower tank, 18...Lower tank expansion member, 19...Transportation tank, 24...
・Nakamoto tank, 25... Uemoto tank, 27... Flat fixed part.

Claims (1)

[Claims] 1. In a large-capacity transformer in which a tank is formed from at least an upper tank and a dish-shaped lower tank, and the contents of the transformer consisting of an iron core, windings, etc. are arranged in the tank, the dish-shaped lower tank is A lower tank is provided with a flat plate fixing part to which a tank can be detachably attached, and a vertical frame protruding from the bottom of this part, and the vertical frame is equipped with a reinforcing beam that is removed during transportation and fixed at the installation site. A large-capacity transformer comprising an expanding member and an upper tank attached to the lower tank expanding member.