SU1474811A1 - Converter of three-phase-to-phase voltage system - Google Patents

Abstract

The invention relates to electrical engineering and can be used in converter equipment. The purpose of the invention is to reduce the weight and size parameters, the laboriousness of manufacturing and increase efficiency while ensuring equal magnitude of phase output voltages and a constant angular shift of their phases when the symmetrical load changes over wide limits. The device comprises a three-core spatial magnetic core 1 with input phase windings 2-4 and an output two-phase winding located on it, consisting of parts 5-9. The number of turns in the phases of the respective windings is equal to. Parts 8.9 and 6.7 of the output winding are respectively equal to the number of turns. On one of the rods is placed part 5 of the output winding, and on the other two - parts 6.8 and 7.9, respectively. One output of part 5 forms a common output output, and two branches are connected to its other output, consisting respectively of parts 6.9 and 8.7 and located on two other rods. Using part 5 as a common output winding for both phases provides a reduction in the mass of this winding and a reduction in energy loss. 2 Il.

Description

when changing in a wide range of symmetrical loads. The device comprises a three-core spatial magnetic core 1 with input phase windings 2-4 and an output two-phase winding located on it, consisting of parts 5-9. The number of turns in the phases of the respective windings is equal to. Parts 8, 9 and 6, 7 of the output winding have respectively an equal number of turns. Part of one is placed on one of the rods.

5 output windings, and the other two - parts 6, 8 and 7, 9, respectively. One output of part 5 forms a common output output, and two branches are connected to its other output, consisting respectively of parts 6, 9 and 8, 7 and located on two other rods x. Using part 5 as a common output winding for both phases provides a reduction in the mass of this winding and a reduction in energy loss. 2 Il.

one

The invention relates to electrical engineering and can be used in automation, measurement and converter technology.

The purpose of the invention is to reduce the overall dimensions, the labor intensity of manufacturing and increase the efficiency while ensuring equality in the magnitude of the phase output voltages and a constant angular shift of their phases when the symmetric load changes over wide limits.

FIG. 1 shows a circuit diagram of the proposed device; in fig. 2 - vector EMF diagram,

The three-phase spatial magnetic cores 1 have three-phase input windings, including phase windings 2-4, with the same number of turns, which can be connected by a star or a triangle (the connection is shown by a star) and an output winding consisting of five parts 5-9. The number of turns of part 5 is proportional to cos 45 °, the number of turns in parts 6 and 7 is the same and proportional to cos 15 °, and in parts 8 and 9 the same and proportional cos 75 To part 5 in two branches are connected in series in two parts of the output winding (parts 5 and 7, in one branch, parts 6 and 8 -. in another), placed on different rods, with large parts along. the number of turns (6 and 7) is included opposite, and the smaller ones (I and 9) - according to.

The Converter operates as follows.

As in the proposed device, the turns are equal in the phases and the ratio of the number of turns of the parts of the output winding corresponds to

W7: Ws: W8 W6: Ws.: W, cos J5 °: cos 45 °; fcos 75 °,

The phase voltages at the output of the device should be equal in magnitude and shifted by the angle / it / 2 with a symmetrical change in the magnitude and nature of the load.

Indeed, when supplying the outputs A, B, C of the input winding 2-4, symmetrically three-phase voltage in parts of the output winding 5-9 will induce electromotive forces.

AT . L1 WF; -Ü W6; ,

43w, 4T w,

 J, .. V

gdv Ey ... E - emf parts output

windings; V, is the input voltage

winding;

W, - the number of turns of the phase, the input winding;

W5-W9 - the number of turns of parts 5-9 of the output winding.

Phase EMF of the exhaust winding is obtained by geometrical addition of the EMF of the parts of the output winding (Fig. 2).

, r-E7 + E8j

E8o E5-E + E

With the above ratio of turns of the parts of the output winding, the phase voltages of the idle are equal in magnitude (Eao-Eeo) and are perpendicular (Eao-EBO). If a symmetrical three-phase voltage is applied to the input winding of the device, then at the same magnitude and nature of the load of the output winding, the phase voltages are equal in magnitude and are shifted by an angle. Moreover, this position is observed when the value of the symmetrical load of the output winding changes from idle mode to short circuit mode.

In this device, the number of turns by the trick of the winding on the corresponding rod in -j3 is less compared to the number of turns of the output winding on each of the two other rods.

Denote the sum of the turns of the parts of the output winding with the number of turns proportional to cos 15 and cos 75 by the letter ru

The number of turns of X in part, ration cos 45, we determine from the proportion

cos 15 ° + cos 75 ° cos 45 °. ,

Ycos 45 °

 cos 75r + cos 75 °

tenЈos 4Ј:

2 cos 45 ° .cos 30 °

n 1

The number of turns of the output winding is

n

6 + 43

W + W6 + W6 + WT + W, n + n + -B

those. there is a decrease in the number of turns of the output winding.

Reducing the number of turns of the output winding reduces the complexity of winding the coils of the device. It should be noted a decrease in the number of connections of parts of the output winding, which also leads to a decrease in the labor intensity of manufacturing the converter.

Taking into account the shift of the phase currents of the output winding, equal we arrive at

0

five

0

five

0

five

0

five

0

five

the conclusion that the current value in the common part of the output winding is more than the phase one in NZ times.

Reducing the total number of turns of the output winding and the fact that for normal operation of the converter, the cross section of the common part of the output winding wire must be -Jz times the wire size of each phase of the output winding separately, leads to a reduced wire consumption for the output winding .

Consequently, the mass of the outwinding winding and the width of the window of the magneto-conductor under the windings are reduced.

Reducing the mass of conductor and magnetic materials in the design of the device while maintaining the same values of specific loads of active materials leads to a decrease in losses in copper and steel, i.e. to increase the efficiency of the device.

Claims (1)

Invention Formula Three-phase voltage system to two-phase converter containing a three-core spatial magnetic circuit with terminals located on its rods connected to input terminals for connecting a three-phase input power supply network and one terminal connected to output two-phase windings of the output windings, each phase with the same number of turns the output winding consists of parts placed on different rods of the magnetic pipeline, the number of turns of which These are referred to as cos 1b: cos 4b: cos 75, and part of the winding, proportional to cos 15, is included oppositely in series with respect to other parts, which is such that, in order to reduce weight and size indicators, labor intensity and simultaneously ensuring equality in magnitude of the phase output voltages and a constant angular shift of their phases when the symmetric load varies over a wide range, the output winding is made of five parts, of which the part of the winding with the number of turns is proportional to cos 45, located on one of the cores of the magnetic circuit, is common to the two phases of the output winding, with one output of this part forming a common output output, and its other output connected by free outputs two branches formed by the remaining parts winding so that each branch includes two successively included parts that have a different number of turns and are located on different, of the other two, rods of the magnetic pipe.