CS230693B1 - Three-phase power transformer especially for unidirectional welding sources - Google Patents

Abstract

The invention falls into the field of construction of three-phase transformers intended primarily for arc welding. The transformer winding is rectangular in shape, in which two and two opposite side parts are folded together and tightened around them by rings of a transformer sheet metal strip. According to the invention, the lower voltage windings are made as disc single-layer coils, which are folded in the middle of their front parts so that the outer surfaces of their side parts form a 120° bend with each other.

Description

RICHTERA JOSEF, BRATISLAVA

Three-phase power transformer especially for DC power sources

The invention falls within the field of construction of three-phase transformers intended primarily for arc welding. the windings of the transformers are of a rectangular shape, in which two and two opposing side portions are each folded together and tightened around them by wrapped rings around the transformer sheet. According to the invention, the low-voltage windings are in the form of disc-shaped single-coils which are folded in the middle of their end portions so that the outer surfaces of their lateral portions clamp each other at an angle of 120.

230 693

- 1 230 693

BACKGROUND OF THE INVENTION The present invention relates to a three-phase power transformer designed especially for unidirectional power sources with forced air cooling.

Currently known transformers of this kind have rectangular phase windings folded together by side sections and pairs of folded side sections are pulled around them by wrapped rings of a transformer plate forming the magnetic circuit of the transformer. The entire ring cavities are filled with winding conductors and insulating Cooling ducts are provided in the winding fronts to increase the efficiency of heat dissipation from the part of the winding tightened by the rings. The higher and lower voltage windings are designed as multi-position single coils axially interlocking. The above-mentioned winding solution has a number of disadvantages, especially when making multi-position low voltage single conductors from an insulated profile conductor, since a low filling coefficient is achieved, which in addition to increasing the diameter of the transformer plate rings. This results in increased transformer plate consumption and no-load losses. is technologically demanding winding of multi-position single coils from profile conductor ·

The above-mentioned disadvantages of the presently known solution d are substantially eliminated by the present invention. The essence of the invention is that the windings of the lower stresses of the individual phases are designed as disc single coils, which are folded in the middle of their fronts so that the outer surfaces of their lateral portions wherein the single coil windings® lower voltage individual

230 693 phases contact each other with the external faces of their lateral parts *

The solution according to the invention achieves an increase in the filling coefficient of the lower voltage winding, which results in a reduction in the consumption of the transformer sheet and a reduction in the no-load losses.

In the front part of the winding, relatively wide winding channels are formed between the higher and lower voltage windings, which will contribute to a considerable improvement in the smoothing of the winding lateral parts, which are wrapped with transformer sheet metal rings. * When folding the windings of the individual phases, there is no need for a folding device, as the elimination of the joints of the side parts of the disc coils defines their exact mutual positioning. * Reduces labor costs when winding lower coil coils.

In the accompanying figures, an exemplary embodiment of a three-phase power transformer according to the invention is shown. Fig. 2 shows a side view of a three-phase power transformer * h and Fig. 2 shows a side elevation of a disk single coil of a lower voltage winding; and Fig. 4 shows a side view with a partial section.

The three-phase power transformer consists of three windings and a rectangular shape in which the windings χ of each of the phases have two and two laterally opposed parts 2 mutually folded and pairs of mutually folded side portions 2 of the rectangular winding χ are pressed around them by wrapped rings χ. The entire cavities of the rings X are filled with winding conductors X and insulating materials. Cooling ducts 2 are provided in the winding end faces χ. The lower voltage windings jednotlivých of the individual phases are designed as disc single coils sú which are bent in the middle of their end portions χ so that the outer surfaces 8 of their side portions 2 form an angle of 120 ° to each other. The lower surfaces of the coil 10 are connected to each other by the outer surfaces & their side portions.

Cooling channels χχ are formed between the lower wires of the lower voltage windings and the lower wires of the higher voltage windings.

Claims (1)

OBJECT OF THE INVENTION 230 693 A three-phase power transformer particularly for unidirectional welding sources having rectangular phase windings, wherein the rectangular windings of each of the phases have two and two laterally opposed portions folded together and pairs of mutually folded lateral portions of the rectangular winding are wrapped around them by wrapped ring bands. wherein the green rings of the rings are filled with winding conductors and insulating materials, and cooling channels are provided in the winding end sections, characterized in that the windings of the lower voltage of the individual phases are designed as disk single coils (6) which are bent in the middle so that the outer surfaces (8) of their side portions (9) enclose an angle 120 with respect to each other, wherein the single coils (6) of the lower voltage windings of the individual phases contact each other with the outer surfaces (8) of their side portions (9).