SU1427428A1 - Conversion transformer - Google Patents

Abstract

The invention relates to electrical engineering. The aim of the invention is to increase reliability by reducing the electrodynamic forces during a short circuit of one part of the valve winding. The transformer contains a magnetic conductor 1, on the rod of which the windings are concentrated: valve 2, network 3 and adjustment 4. The valve winding 2 is split into four parts. The adjusting winding 4 consists of a section of the load section.

Description

adjustment from and from the fine adjustment section. Each section is made of several groups and steps. The coarse control coil groups are connected in series, at about the ccIJ and fine control stages, the middle coils of the coarse control section are located, the even stages of the fine control are grouped on one side relative to the middle of the winding, and the odd ones on the other side. 2 Il.

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The invention relates to electrical engineering, in particular to a transformer, and relates to transformers designed to power the conversion units, for example, in electrolysis plants.

The purpose of the invention is to increase reliability by reducing the electrodynamic forces during short circuits.

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Figure 1 shows the windings of the transformer phase, located in the window of the magnetic circuit, section; 2 is a schematic of the connection of the control and network windings.

The transformer contains a magnetic conductor on the rod 1 of which the windings are concentrically arranged: valve-. 2, net 3 and adjustment 4. The valve winding 2 is split into four parts: parts 5 and 6, connected in a star and consisting of parallel branches Vg and Y, respectively, and parts 7 and 8, connected in a triangle and consisting of parallel Branches D and Dzo The adjusting winding 4 consists of a coarse adjustment section j which is divided into two groups of coils 9 and 10 located along the ends of the winding. The fine control section consists of eight stages 11-18, connected in series, with stage 11 connected to the beginning of the section, and stage 18 to its end. The first stage 11 is located directly, for example, near a group of coils 9, the second stage 12 is located near a group of coils 10. Fine adjustment steps are located so that in the upper group there are steps, for example, with odd numbers - 11, 12 13, 14, counted from coils coarse adjustment sections towards the middle of

coils, and in the lower group - steps with even numbers - 15, 16, 17, 18, counting from the middle of the winding to the coils of the coarse regulation section.

The groups of coils 9 and 10 of the coarse adjustment section are connected in series, with the middle coils of the section located at the junction of the coarse and fine adjustment section.

The voltage regulation of the valve winding is provided by changing the number of turns of the power winding (CO) by sequentially connecting (or disconnecting) the thin and coarse regulation sections to it, carried out by the switching device 19.

The beginning of the group of coils 9 is connected with the beginning of the phase, for example, A,. And with the fixed contact 20 of the reverser of the switching device. The end of the group of coils 10 is connected to the fixed contact 21 of the reverser. The movable contact 22 of the switching device reverser is connected to the beginning of the fine adjustment section and can occupy two positions, in one of which it closes the contact 20, in the other it closes the contact 21.

The contactor of the switching device has movable contacts 23 and 24, which, when moving, sequentially close the fixed contacts 25-32, to which the tapings of the corresponding stages of the fine control section are connected: contact 23 can close contact 25 of level 11, contact 27 of level 12, contact 29 of level 13, contact 31 of step 14, contact 24 can close contact 26 of step 18, contact 28 of step 17, - contact 30 of step 16, contact 32 of step 15.

To the contactor of the switching device is connected the start of the CO, the end of which is connected to the end of phase X. 5

When the transformer operates during voltage regulation, the RO is connected in the following order: first the steps of the fine control section alternately, then the thin steps of the switch are disconnected and the coarse adjustment section is turned on, then the steps of the thin section are alternately connected to the switched on coarse section. This scheme is implemented by the constructive interconnection of the elements of the switching device 19 (reverser, contactor, etc.).

In accordance with this scheme, at the beginning of the adjustment process, the movable 20 contacts 22 are in the position where the contacts 20 are closed, which corresponds to the disconnection of the coarse section. In this case, the movable contact 23 closes the fixed contact 25, due to 25 which makes the stage 11 of the fine control section turn on in the CO circuit. Upon further movement of the contactor, contacts 23-25 open and contacts 24-26 close, thanks to which, steps 11 and 18 will be connected to the CO located near the coils of the coarse section symmetrically with respect to the center of the winding i. the zone of intersection of parts

As the moving contacts 23 and 24 move further, the stages 12, 17, 13, 16, 14, 15 are alternately connected, located on one side and the other side of the center of the winding, respectively.

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After the fine control section is fully turned on, the movable contact 22 will take a position where contacts 21 are closed and contact 23 returns to its original position by closing contact 25. Thus, the coarse adjustment section will be connected to CO. It consists of two groups of coils connected in series and located on both sides of the symmetry axis of the winding, and stage 11 of the thin, control section. At the same time, asymmetry in one step does not have a practical effect on the distribution of currents in the VO, which is confirmed by calculations and experiments.

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At the next stage of operation of the switching device with closed contacts 21-22, the movable contacts 23 and 24 are moved according to the described scheme, the commissioning of the fine control stage.

In the operating mode, regardless of the number of included steps sh1.sections, the picture of current, and hence electrodynamic loads, will be symmetrical with respect to the VO.

In the partial short-circuit mode, when the electromagnetic field is asymmetrical, regardless of the position of the switching device in the RO, circulating currents cannot occur, since their flow paths are excluded. Consequently, the negative effect of the limiting currents on the current distribution in the VO is excluded, which determines the reduction of the electrodynamic forces in the zone of the junction of the short-circuited and non-shorted parts.

Claims (1)

Invention Formula A transformer transformer containing a three-rod mapped wire, network, control and valve windings, the phase coils of which are concentrically located on the cores of the magnetic conductor, while the valve winding is split in height into an even number of parts consisting of parallel branches, and half of the parts are connected into a star which alternate with the other half of the parts connected in delta, the adjusting winding connected in series with the mains contains a coarse adjustment section of two pp coils and section. fine adjustment located in the middle winding zone between the groups of coils of the coarse adjustment section, and the fine adjustment section. It consists of sequentially connected steps, the first of which is connected to the beginning and the last to the end of the section and the first and second stages are located in close proximity to the coil groups of the coarse adjustment section, respectively, characterized in that, in order to increase reliability by reducing electrodynamic forces at short circuit of one part of a valve winding, a group of coils of the coarse regulation section of the connection51427А286 These are consistent, with the middle coils of the middle section of the winding being on one side relative to the center of the thin section of the sections of the thin section of the winding, and the odd ones on the other side of the control, even the front side. A l GGL L-4 l / yL 1 i L .. 27 12 117 28 75 13  thirty  TI .zh g, Contactor P g i FIG. 2