SU858187A1 - Three-phase ac voltage-to-12 pulse dc converter - Google Patents

Description

The invention relates to the field of conversion technology and can be used as a direct current source with a twelvefold pulsation frequency. Three-phase AC / DC converters are known to provide a twelve-fold ripple frequency of 1 and 2 that provide a twelve-fold frequency. The disadvantages of the transducers are the presence of an equalizing reactor, as well as a large number of spurs of the transfusion valve and increased losses in the valves. Also known is a three-phase transient voltage-to-constant twelve-pulse converter 3, containing a six-phase bridge rectifier and a transformer with two secondary windings, of which is connected in a star and is opposite to another when the ratio of phase voltages is 1: (-0 - 1 ). The disadvantage of such a converter is the irregular type copying of the transfer mater and the absence of compensation that magnetizes the transformer when the primary windings are connected to a star. Most bland to the proposed. is a three-phase alternating voltage converter into a twelve-pulse constant, containing a six-phase valve and a transformer, the three-phase secondary winding of which is connected in delta and made in each phase with a tap, dividing the turns of this winding in the 0-), wearing j and the additional winding, each of which is connected between the tap-off of the secondary winding of the corresponding phase and the output for connecting the corresponding phase of the valve bridge 4 J. The disadvantage of this device is unsatisfactory overall dimensions due to the significant installed capacity of the transformer. The purpose of the invention is to improve the weight and size parameters. The goal is achieved by the fact that in a three-phase alternating voltage converter into a twelve-pulse constant, there is a six-phase valve bridge and a transformer, the three-phase secondary winding of which is connected in a triangle and made in each phase with a tap which splits the turns of this winding in relation to

-).

and additional covers, each of which is connected between the tap-off of the secondary winding of the corresponding phase and the terminals for connecting the corresponding phase of the valve bridge, the number of turns of each additional. phase of the corresponding phase refers to the number of turns of the secondary winding connected in a three-piece winding of the same phase as

(

and.

In FIG. 1 shows a cxeMf converter; in fig. 2 is a vector diagram, according to the principle of the combination of the voltage of the windings of the groups.

The converter consists of a power transformer (the primary winding is not shown in Fig. 1) with a secondary winding 1 connected in a triangle and additional windings 2 Each phase winding of a triangle ax, bo, CZ has a crO1 "w main additional output connected to the opposite terminal with one of the additional windings 2, the voltage of which is ahead in phase aa 60 of the voltage of the corresponding winding of 1 triangle. Thus, the additional output a of the winding ah is connected to the output from the winding of 2. g, the voltage of which is ahead of the voltage of the winding by 60 times ha.

Similarly, output b is connected to output a and output c to output. The rest of the output of windings 1 and 2 are connected to the input of a six-phase bridge rectifier on valves 1YAX 3-14, the output of which is connected to load 15.

Phase voltages A x, a x and a-Xj, as well as the voltage corresponding to the coil windings located on the two or more rods x,,, and cz,, are chosen in the ratio

.

The curve of the rectified voltage at the load 9 is formed by a twelve-fold accelerated voltage system.

(fig. 2):, bi.j4y, 0, ГГ

, aaXa ax biC, zax vb% xa:; c2t2

 xjajb vcz.,

in accordance with the specified order of voltage following, the load current 15 will flow through the valves: 6–14, 4–14, 7–14, 7–11, 7–12 3–12, 8–12, 8–10, 8 - 13, 5-13 6 - 13, 6 - 9.

In this device, one six-phase voltage system is created by the full voltage of the triangle windings, and the other six-phase system is shifted by 30 el. hail, by adding the total voltage of one phase of a triangle to a part of the voltage of the other 5 of its phase, following according to alternation over the first, with the voltage of the winding of group 2, which is ahead of the specified voltage of the first phase of the triangle by 60. So, for example, (FIG. 2) is obtained as a result of the geometric layer) (the stresses of the CSA + U2, ... opposite phase voltage (. the three additions of the specified vectors of

reverse order ie Chokh Vtori six-system

has vectors equal to the first system

"Shifted by 30 el.grad., Resulting in the fact that the summable voltages

Aux, Uzc4, related

f -) (4

The duration of the current flow through the valve in the proposed converter is 30 electr., And for the valves connected to the windings 2 and 90 zl. hail. for valves connected to the output of a triangle. The typical power S of the transformer of the proposed device is equal to 1, 12 straightened Pd, i.e. S 1.12 Pd.

The selected ratio of the number of turns of the secondary and additional windings allows to reduce the typical power of the transformer and thus

to improve the mass and overall performance of the entire converter.

Fore || la invention

A three-phase alternating voltage converter into a twelve-pulse constant, containing a six-phase valve bridge and a transformer, the three-phase inlet winding of which is connected in delta and made in each phase with a tap that divides the windings of this winding in relation to

ii

H-)

five

and additional windings, from which it is connected between the tap-off of the secondary winding of the corresponding phase and the outlet for connecting the corresponding phase of the gate bridge, with the fact that in order to improve the mass-dimensional parameters, the number of turns the complementary windings of the corresponding phase refers to the number of turns of the secondary winding of the same phase as

(w-ib

Sources of information taken into account in the examination

1.Kogan I.L. Electronic and ion converters. Hey, M., 1956.

2. Authors certificate of the USSR 504281, cl. H 02 M 7/06, 1976.

3. USSR author's certificate 540334, Chl. H 02 H j7 / 0 €,.

4. USSR author's certificate according to the application I I 3.2424508, cl. N 02 And 7/06,

5 1976.

Claims (1)

Claim A three-phase AC to twelve-pulse DC converter, containing a six-phase valve bridge and a transformer, the three-phase secondary winding of which is connected in a triangle and made in each phase with a tap, dividing the turns of this winding in relation to and additional windings, each of which is connected between the tap of the secondary winding of the corresponding phase and the conclusion "* for connecting the corresponding phase of the valve bridge, with the same * Shch and y with i * that, in order to improve the overall dimensions, the number turns of each of the additional windings of the corresponding phase refers to the number of turns of the secondary winding of the same phase as