JPS60766B2 - split type transformer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION When a transformer is divided into a plurality of unit transformers due to severe transportation limitations, gradual increase in transformer capacity, etc., the present invention enables compact and easy parallelization of each unit transformer. This invention relates to a split transformer that can be connected.

Conventionally, when connecting a plurality of unit transformers in a variable series, the coil lead wires drawn out from the coils of each unit transformer were connected in the space of a tank or in a duct dedicated to connection leads.

In this case, when the lead wires connected in parallel are of high voltage, a considerably large space is required due to insulation requirements. Therefore, the present invention has been made in view of the above points, and an object of the present invention is to provide a split type transformer in which the connection space is reduced and the connection work can be easily performed. An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

FIG. 1 shows a connection example in which two three-phase three-leg iron core transformers are connected in parallel, and A and B are the contents of each transformer connected in parallel. The transformer contents A has coils 4A, 4, and 4 wound around the legs of a three-leg iron core 3. A cross section of one of these phases (W phase) is shown in FIG. The coils 4A, (4B,) are inner (low voltage) coils 4a, (
4b,) and an outer (high voltage) coil 4a2 (4Q). When connecting the two transformers A and B in parallel, the line end lead 40 of the coil 4 is connected to the line stagnation lead 41 of the coil 48 via the coil crossover wire 1.
At this time, the coil crossover wire 1 is made to pass between the legs of the iron core 3, and also to pass through the same potential portion of the corresponding coil inside the transformer. In the figure, W is the coil crossover wire 1
The end of the coil line and the end of the coil line are shown. Also, W2 is coil 4
The line end of line B is shown, and both line ends W and W2 are connected to lead out to a W-phase bushing (not shown). The coil crossover wire 1 at the end of the line has inner coils 4a, (4b,) and outer coils 4a5 (4 et al.) as shown in Figure 2.
Both are also equipped with mounting stripes. - The coil crossover wire shown in Appendix 2 connects the neutral point lead, and connects the contents A and B of both transformers by the same means as the connection between the line end leads 40 and 41 described above. The coils are connected in parallel.

Here, the coil crossover wire 1 that connects the line end leads 40 and 41 and the coil crossover wire 2 that connects the neutral point lead are arranged in opposite directions so that the magnetic fluxes created by the mutual lead wire currents are mutually canceled. is derived. This prevents problems such as an increase in iron loss due to the magnetic flux created by the crossover wire current. Furthermore, the first
Although the coil crossover wire 2 on the neutral point IJ side is omitted in the figure, it will be clear from the explanation of FIG. 2. Further V
The phase and U phase are also connected in parallel in the manner described above. Here, in the U phase, the coil crossover wire 1 is aligned with the coils 4A3 and 4B3 outside the iron core. In the above embodiment, a three-phase three-legged iron core transformer has been described, but as shown in FIG. 3, the same implementation is possible even when two single-phase three-legged iron core transformers are connected in parallel. FIG. 4 shows another embodiment of the present invention, in which the present invention is implemented when two three-phase transformers are connected in parallel.

In this embodiment, the coils 4C and 4D of the first unit transformer C and the second unit transformer D are connected in parallel by a coil crossover wire 12 for low voltage side connection and a coil crossover wire 13 for high voltage side connection, respectively. ing. The low-voltage line end bushing 7 and the high-voltage line end bushing 5 are led out so that the currents in the coil crossover wires 12 and 13 are opposite to each other. The neutral point of the low voltage side coil of the other unit transformer D is connected and the voltage is led out by the low voltage neutral point bushing 8. The coil crossover wires 12 and 13 of both unit transformers C and D are connected to flanged ducts I0 provided on the surfaces where the respective transformer tanks face each other.
Let them guide you through. This situation will be clear from FIG. If the flanged ducts 10 are provided on opposite sides of the tank in the unit transformer, the bushings 5 and 7 can be attached via the bushing pockets 9 using the flanged ducts 10a. .
Further, it is preferable to provide a partition member 11 at the joint between the flanged ducts 10 or between the flanged duct 10a and the bushing pocket 9. This partition member 1
As a first example, an oil-filled wall bushing or a wall baser made of an insulator with a central conductor inserted therein can be used. In addition, when considering future capacity increases, if a crossover wire or a connecting duct with a flange is installed in the coil in advance, parallel connection work at the time of expansion will be facilitated. As explained above, according to the present invention, when a plurality of transformers are connected in parallel to cope with an increase in capacity, or due to transportation limitations, the transformer is divided into multiple transformers and manufactured, and these are connected in parallel on site. In split type transformers that are combined to make one transformer, one way to connect each unit transformer in parallel is to connect one lead of the coil of one unit transformer to the other. The first wire is connected between one end lead of the coil of the unit transformer and the same potential part of both coils.
The other end lead of the coil of the one unit transformer is connected to the other end lead of the coil of the other unit transformer, that is, the same potential parts of both coils are connected by a second lead. They are connected by crossover wires, and the magnetic fluxes created by the first and second crossover wire currents cancel each other out, so the iron core is excited by the magnetic flux created by the crossover lead currents, reducing iron loss. It is possible to minimize the increase in

Also, abnormal vibrations that may occur in some cases can be prevented. By arranging the crossover wire to pass between the core legs, that is, to align it with the coil, it becomes possible to significantly reduce the space required for connection. In addition, by providing a connecting duct with a flange for parallel connection leads on each unit transformer, parallel connection work is facilitated, and especially when an accident occurs in one unit transformer, it is possible to connect the healthy transformer and the faulty transformer. By disconnecting the connecting duct, it is possible to continue operating at a reduced capacity. Further, if a partition member is arranged in the connecting duct portion to separate the insulating oil of both transformers, it is possible to facilitate the separation of the faulty transformer and the normal transformer and the oil disposal work. In the present invention, the number of iron core legs is not limited to the above-mentioned embodiments, but can be applied to various numbers of legs.

[Brief explanation of drawings]

FIG. 1 shows a three-phase three-leg iron core transformer 2 showing an embodiment of the present invention.
A schematic explanatory diagram showing an example of parallel connection of units, FIG. 2 is a sectional view to explain the main part of FIG. An explanatory diagram of two three-phase transformers connected in parallel showing still another embodiment of the present invention, FIG. 5 is a side view of FIG. 4. 1, 2... Coil crossover wire, 3... Iron core, 4... Coil ,A,B
...Transformer contents, 40, 41...Line end leads. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. In a device in which a plurality of divided unit transformers are connected in parallel to form one transformer, one end lead of the coil of the first unit transformer is connected to one end lead of the first unit transformer and one end lead of the coil of the same potential part of the second unit transformer by a first crossover wire, and Connect the other end lead of the coil to the second
of the unit transformer, the other end lead of the first unit transformer and the other end lead of the coil of the same potential part are connected by a second crossover wire, and the first and second crossover wires A split type transformer in which each lead is directed in a direction where the magnetic flux created by the current cancels each other out. 2. The split type transformer according to claim 1, wherein the crossover wire is arranged between the core legs. 3. The split type transformer according to claim 1, wherein the first unit transformer and the second unit transformer are connected by a flanged connection duct, and a crossover wire is inserted through the duct. 4. The split type transformer according to claim 1, wherein one end lead of the coil is a line end lead, and the other end lead of the coil is a neutral point lead. 5. The split transformer according to claim 1, wherein a partition member for partitioning the first and second unit transformers is provided between the flanged connection ducts.