DE3411141C2 - Transformer with high current bushing - Google Patents

Abstract

For transformers of this type with triangular windings on iron core legs arranged in a row, it is known to use a cross-section composed of three V-shaped conductors to form a three-pointed star as a compensated high-current line outside the high-current bushing arrangement. According to the invention, three plate-shaped triangular connectors (4), each twisted by 120 ° against each other in their main plane of extent, are located in the transformer directly on the inside of the high-current bushing arrangement (3) and at the same time represent part of the same, with the outlets (5) of the central winding (1) against each other are crossed out and parallel to each other in vertical planes to downwardly pointing gussets of two triangular connectors (4), whereas the outlets (6) of the two other windings (1) are guided to the triangular connectors (4) without crossing. This arrangement can be produced simply and economically, especially in the area of high-current bushings, and due to its largely compensated design, it is free of hot spots and, for this reason, can also be used for currents above 80 kA.

Description

- that the three twisted against each other in their main extension plane by 120 °, Triangular connectors (4) are plate-shaped, directly on the inside of the high-current bushing arrangement (3) lie and at the same time represent a part of it,

- That the leads (5) of the middle winding (1) crossed against each other and too perpendicular downward-facing gussets are guided by two triangular connectors (4),

- that the outlets (6) of the two other windings (1) to the triangular connectors (4) are led

- By each of these windings (1) a lead (6) to a 60 ° out the vertical swiveled gusset of the triangular connector also having the gusset pointing vertically downwards (4) is performed and

- By each of these two windings (1) the other outlet (6) to one of the two gussets of the third triangular connector, which are pivoted by 30 ° against the horizontal, above the other two (4) is performed and

- That no metallic parts are in the space between the triangular connectors (4) are arranged.

High-current winding (1) made of double-disc coils all assigned to the same iron core leg Double disc coils via the coil exit leads and via the triangular connector (4) electrically are connected in parallel.

2. Transformer according to claim 1, characterized in that stiffeners of the triangular connector (4) and / or the transformer tank provided exclusively outside the magnetic flux are.

3. Transformer according to claim 1 or 2, characterized in that the triangular connector (4) has a have a sickle shape.

4. Transformer according to one of claims 1 to

3, characterized in that the leads (6) of the windings (1) on the outer iron core legs are moved to aulien.

5. Transformer according to one of claims 1 to

4, characterized in that to enforce a uniform current distribution over the discharge cross-section the distance from current paths through which current flows in opposite directions in the diverters (6) is greater, the shorter the Current paths are.

6. Transformer according to one of claims 1 to

5, characterized in that when executing the

The invention relates to transformers with delta-connected windings arranged in a row Iron core legs and with a high-current bushing for connection to a cross-section three V-shaped conductors combined to form a three-pointed star, self-compensated high-current line. The leads of the middle winding are parallel to each other in perpendicular planes to perpendicular triangular connectors pointing downwards and the leads of the other two outer windings without crossing guided

Such a transformer is known from DE-OS 32 42 438. In this transformer, however, are only two of the triangular connectors housed within the transformer tank, the third triangular connector on the other hand lies outside the transformer tank.

For this reason, four high-current conductors are to be led through the boiler wall to the outside. These four high-current conductors are designed as panels standing next to each other at the same height and therefore with regard to their field effect to the outside is not compensated as well as the subsequent high-current line of three V-shaped conductors combined to form a three-pointed star.

The invention is therefore based on the object of transformers for connection to a high-current line to create a space-saving arrangement that is already economical in the field of High current bushings is fully compensated.

According to the invention, this object is in a transformer of the type mentioned with a High current bushing with the characterizing features of claim 1 solved.

According to advantageous embodiments of the invention, the triangular connectors and the boiler are stiffeners Provided exclusively outside of the magnetic flux, and the triangular connectors have a sickle-shaped Shape.

According to expedient developments of the invention, the leads of the windings are on the outside lying iron core legs offset to the outside and is to enforce a uniform current distribution The distance from current paths through which current flows in opposite directions over the lead-out cross-section The shorter the current paths, the greater the diverter, so that the influence of the lower ohmic resistance of the short current paths due to magnetic displacement of the current from this area is compensated.

When applying the arrangement according to the invention to an embodiment of the high-current windings all double-disk coils assigned to the same iron core leg are expediently made of double-disk coils Electrically connected in parallel via coil leads and the associated triangular connector.

The arrangement according to the invention is in Transfor-

mators with high current bushings very advantageous, because practically no hot spots occur as a result of largely compensated line routing and one uniform power distribution to the individual terminals can be achieved, so that transformers can be implemented with currents up to over 80 kA.

Embodiments of the invention are explained in more detail with reference to a drawing

F i g. 1 the front view of a transformer winding set with outlets and triangular connectors and

F i g. Figure 2 is a top view thereof with the triangular connectors removed.

Windings 1 form, in the usual manner, a winding set for installation in a not shown oil-filled transformer tank. Within the windings 1 are also for the sake of clarity High-voltage windings, not shown, and iron core legs connected to one another by yokes at the ends intended.

The windings 1 are high-current windings from a single winding conductor with a large cross-section or as in Fig. 1 shown on the left winding from a plurality of electrically connected in parallel Disc coil windings built up In addition, the windings 1 belong to a three-phase system and are connected to each other in a delta connection. For this purpose there are leads 5 of the middle winding 1 and outlets 6 of the two outer windings 1 led to triangular connectors 4, which the ends of the windings 1 interconnect, and at the same time emanating from the ends of the outlets 5 and 6 Guide the connecting bolt 2 of a high-current bushing 3. However, the diversions 5 are opposite the diversions 6 via a breakthrough or as in FIG. 2 indicated, laterally with one another via an overpass 7 reversed.

The triangular connectors 4 have different sizes depending on the absolute size and the equalizing current to be expected Shape. Overall, the three each form the shape of a flat V from two gussets Triangle connector 4 a three-pointed star. Each of these six gussets holds one of the leads 5 or 6. The left triangle connector 4 most clearly shows the shape of the flat V and requires the least amount on conductor material, preferably copper. The right and upper triangular connectors 4 have the shape of an obtuse triangle with cut corners.

Required reinforcements in the area of the bushings and the triangular connector 4 on the transformer tank are outside the area of the connecting bolt 2, for example indicated by a dashed line Reached the bridge. The dashed line enclosing a crescent-shaped area in the upper triangular connector 4 shows the distribution of the current in this component.

Current paths of different lengths occur in the outgoing lines 6 from the outer windings 1 which represent different sized ohmic resistances for the operating current and an uneven distribution the same effect on the total cross section of each of the outlets 6. For at least partial Compensation for this unequal current distribution is the vertical distance from the same winding in each case 1 associated diversions 6 by tilting the same, the greater the shorter the current path is. Since the respective associated discharge lines 6 in opposite directions from the operating current are traversed, the magnetic fields generated by this try the operating current as far as possible to move apart and thereby compensate for the first-mentioned effect due to unequal ohmic Resistances.

1 sheet of drawings

Claims (1)

Patent claims: 1. Transformer with low-voltage windings connected in a triangle via triangular connectors (1) on iron core legs arranged in a row and with a high-current bushing arrangement (3) for connection to a cross-section of three V-shaped conductors to form a three-way conductor Star compound self-compensated high-current line, with diversions (5) of the middle Winding (1) parallel to each other in perpendicular planes to those facing vertically downwards Triangular connectors are guided and wherein the outlets (6) of the other two windings (1) do not cross over are performed, characterized in that