RU2557665C2 - Transformer output current control method and transformer for its implementation - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention relates to electrical engineering and can be used as a power supply with the sloping external characteristics to ensure smooth current control without change of voltage value x.x. The transformer output current control by change of magnetic coupling between the input - primary and output - secondary windings is performed by putting into and out of the operation, continuous and smooth switching, turns in input windings, formed by primary and additional windings. It results in invariance of total number of turns in the input winding, constancy of transformation ratio. The transformer contains a two-rod magnetic conductor on the first core of which the single-layer input - primary winding with two network inputs is located, on the second core the output - secondary winding is located. The guide is implemented with the mobile switch contacting with the bared parts of turns of the windings forming contact paths. The additional winding is implemented single-layer, its number of turns is equal to number of turns of the input - primary winding and is located above the output winding.

EFFECT: expansion of range of control and decrease of material capacity.

3 cl, 5 dwg

Description

The invention relates to electrical technology and can be used in any industry as a power source with falling external characteristics, in which it is necessary to provide smooth current control without changing the value of the open circuit voltage.

Known transformers, or rather autotransformers (AS USSR No. 1088078, Cl. H01F 31/02, H02F 29/06, published 08.10.80), using the principle of voltage division by moving the switch (current collector) along the contact track.

The disadvantage of such a transformer lies in the method of regulating the output current, which consists in the fact that when regulating the output current, the output voltage changes proportionally to it

There are transformers with movable, fixed and additional windings, the current in which is controlled by changing the magnetic coupling between the coils of the windings as a result of changing the distance between them by moving one of the coils along the core of a long magnetic circuit (AS No. 860154, class H01F 38/08, B23K 9/00, published. 30.08.81).

The method of regulating the current of the transformer by longitudinally moving the windings along the rods of the magnetic circuit, thereby changing the distance, and accordingly the magnetic coupling between them, determines the large length of these rods, and also requires a cumbersome movement mechanism, which, in turn, causes a large level of acoustic noise due to non-rigid fixation of the moving coils, as a result of which transformers of this design have large dimensions, weight, metal consumption and a narrow range of regulation of the output current.

The objective of the invention is the creation of a method for regulating the output current of a transformer and such a transformer in which the change in magnetic coupling, at a constant transformation ratio, between the input - primary and output - secondary windings, as a result of changing the distance between them would be carried out by non-mechanical and not longitudinal movement , which would allow to expand the range of smooth regulation of the output current, at a constant output voltage of idling, to simplify the design of the transformer, reduce s its materials consumption, dimensions, weight, and reduce the level of acoustic noise.

The problem is solved in that in the method for regulating the output current of the transformer, at a constant transformation ratio by changing the magnetic coupling between the input - primary and output - secondary windings by moving them, according to the invention, the input - primary winding is moved across the rods to increase the output current of the transformer by synchronous decommissioning of the number of turns in the input - primary winding, and putting into operation the same number of turns in the additional winding located on top output - the secondary winding, and to reduce the output current of the transformer, on the contrary, synchronously deactivate the number of turns in the additional winding and put into operation the same number of turns in the input - primary winding.

The objective of the invention is also solved by the fact that in a transformer containing: a two-core magnetic circuit, on the first rod of which there is a single-layer input - primary winding, on the second rod there is an output - secondary winding, an additional winding guiding with a movable switch in contact with the exposed parts of the winding turns, forming contact tracks, according to the invention, the additional winding is made single-layer, its number of turns is equal to the number of turns of the input - primary winding and is located x the output winding, while the winding of the input primary winding and the additional winding, in order to comply with the correct phasing, are made in opposite directions and in different directions, i.e. the winding of the primary winding starts from left to right, and the direction of the turns is left, the winding of the additional winding is reversed from right to left, and the direction of the turns is right, with the first network input connected to the end of the primary winding, the beginning of which is not involved, the second network input is connected to the end of the additional windings, the beginning of which is not involved.

In addition, in a transformer designed for welding, the upper limit of the short circuit current is limited to prevent the destruction of the transformer and ensure the upper limit of the PV to 60%.

Moreover, in the outer layer of the input - primary winding, 30% of the turns of the total number of turns of the input - primary winding are located, and in the additional winding, respectively, 30% of the turns of all turns of the primary winding are also located.

Below is a detailed description of an example embodiment of the invention with reference to the accompanying drawings, in which FIG. 1 shows a general view of a transformer; FIG. 2 is a circuit diagram of a transformer; FIG. 3 is an electromechanical diagram of a transformer for welding; FIG. 4 is a transformer diagram for a minimum output current; FIG. 5 is a transformer diagram for maximum output current.

The proposed transformer contains a magnetic circuit 1 of known design (see Fig. 1), which includes the first rod 2, the second rod 3 and two yokes, on the first rod 2 there is a motionless single-layer input - primary winding 4, and on the second rod 3 also motionless - output - secondary winding 5, on top of which an additional single-layer winding 6 is installed, the number of turns of which is equal to the number of turns of the input - primary winding 4, the winding of the input - primary winding 4 and additional winding 6 to comply with the correct phaser Application is made in different directions and oppositely (see. Fig. 2), i.e. winding of the primary winding 4 starts from left to right, and the direction of the turns is left, the winding of the additional winding 6 is made vice versa from right to left, and the direction of the turns is right, and the primary winding 4 is made separately, impregnated with an insulating compound and is an integral part of the transformer, accordingly, the secondary winding 5, on top of which an additional single-layer winding 6 is installed, is also made separately, before the transformer is assembled, it is impregnated with an insulating compound and is a component nth transformer part (winding manufacturing technology is known in the transformer industry), while on the outer insulating layers 7 of FIG. 1, along the axial lines of the input - primary winding 4 and the additional winding 6, windows are cut through which the bare upper portions of the turns of the input - primary 4 and additional 6 windings are viewed, forming contact tracks along which, in contact with the turns, it can move along the guide 8, a switch 9 of a known construction, consisting of an engine with an axis pressed into it - a jumper, on which, at the ends, movable carbon-graphite brushes and (or) rollers are installed, the first network input 10 being connected to the end of the primary quipment 4, which involved not start, the second network 11 is connected to the input end of the auxiliary winding 6 whose origin is inactive.

In addition, in the transformer intended for welding (see Fig. 3), the upper limit of the short circuit current is limited to prevent the destruction of the transformer and ensure the upper limit of the PV to 60%.

Moreover, in the outer layer of the input - primary winding 4 there are 30% of the turns of the total number of turns of the input - primary winding, and in the additional winding 6, respectively, 30% of the turns of all the turns of the primary winding are also located.

The transformer in accordance with the invention operates as follows.

In the initial state (see Fig. 2), the switch 9 is installed in the left extreme position, while the current from the network supplied to the input of the transformer is closed by the circuit: the first network input 10, the end of the primary winding 4, the primary winding 4, the beginning of the primary windings 4, switch 9, second network input 11, i.e. the input winding is the primary winding 4.

This position of the switch 9 provides the minimum current at the output of the transformer, see the transformer circuit shown (Fig. 4) for the minimum output current.

Indeed, the input primary winding 4 and the output winding 5 are located on different rods and therefore are located at the maximum possible distance from each other, which ensures minimal magnetic coupling between them.

To increase the output current of the transformer, the switch 9 is smoothly shifted to the right by the desired amount, while there is a smooth transverse movement of the input - primary winding 4 from the first rod 2 to the second rod 3.

Physically, this process occurs as follows. When the switch 9 is moved from the left extreme position (Fig. 2) to the extreme right position (line image), the turns are sequentially taken out of the primary winding 4, and simultaneously, the same number of turns are put into operation in the additional winding 6.

The right extreme position of the switch 9 corresponds to the maximum output current of the transformer, while the current coming from the network to the input of the transformer is closed by the circuit: the first network input 10; switch 9 (line art); start of additional winding 6; additional winding 6; the end of the additional winding 6; the second network input 11, which corresponds to the above diagram in FIG. 5, here the input - already an additional winding 6 is located on top of the secondary winding 5, and they are on the same rod, so the magnetic coupling between them is maximum.

When moving the switch 9 from the right extreme position to the left, the reverse process occurs, and the output current of the transformer decreases.

Whatever position the switch 9 is in, the total number of turns (participating in the work) in the input circuit remains unchanged, i.e. the transformation coefficient also remains unchanged, which ensures a constant voltage at the transformer output in idle mode.

Comparing the two images of FIG. 4 and FIG. 5 at the same time, it is seen that there was a transverse movement of the input winding.

Thus, in the proposed transformer, in the process of regulating the output current, the input winding can serve as a primary winding 4, and an additional winding 6 and / or a combination thereof.

The proposed method for the transverse movement of the input winding significantly extends the range of regulation of the output current, simplifies the design of the transformer, reduces the size, metal consumption, weight and level of acoustic noise.

Claims (3)

1. The method of regulating the output current of the transformer by changing the magnetic coupling between the input - primary and output - secondary windings by introducing and putting into operation, continuous and smooth switching, turns in the windings, characterized in that the introduction and putting into operation the number of turns are made in the input winding formed by the primary and secondary windings, in order to increase the output current of the transformer, the number of turns in the primary winding is synchronously taken out of operation and the same number of turns in the additional winding is put into operation in turn, and to reduce the output current of the transformer, on the contrary, the number of turns in the additional winding is synchronously taken out of operation and the same number of turns in the primary winding is put into operation, which causes the total number of turns in the input winding to remain unchanged, the transformation coefficient to be constant and the open-circuit voltage to be constant at the output - the secondary winding, while the number of turns in the output winding remains unchanged. 2. A transformer containing a magnetic circuit, which includes the first rod, second rod and two yokes, on the first rod there is a single-layer input - primary winding, and on the second rod output - secondary and additional windings, contact tracks on top of the windings, a guide with a switch, in contact with contact tracks, consisting of a slide with an axis pressed into it - a jumper, on which, at the ends, movable carbon-graphite brushes and (or) rollers are installed, characterized in that, in order to expand the range it smoothly controls the output current, at a constant output open-circuit voltage, simplifies the design of the transformer, reduces its material consumption, size, weight and reduces the level of acoustic noise, the additional winding is made single-layer, its number of turns is equal to the number of turns of the input - primary winding and is located on top of the output - secondary winding, winding of the input - primary winding and additional winding, in order to comply with the correct phasing, is performed in opposite directions and in different directions, i.e. the winding of the input - primary winding starts from left to right and the direction of the turns is left, the additional winding is reversed from right to left and the direction of the turns is right, with the first network input connected to the end of the primary winding, the second network input connected to the end of the additional winding . 3. The transformer according to claim 2, characterized in that, in order to limit the upper limit of the short circuit current, 30% of the turns of the total number of turns of the input - primary winding are located in the outer layer of the input - primary winding, and 30 are also located in the additional winding, respectively % turns from all turns of the primary winding.

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