SU1409991A1 - Three-phase stabilized a.c. voltage source - Google Patents

Abstract

The invention relates to secondary power sources. The aim of the invention is to reduce the installed power of transformer equipment. The goal is achieved by introducing a three-phase transformer (autotransformer) 19 with taps 20 connected to the input terminals 1-3 for connecting the corresponding phases of the first voltage supply network, taps 21 connected to the input terminals 4-6 for connecting according to

Description

(L

with

x; o

phases of the second supply voltage, as well as taps 22 connected to the second output pins 29 of booster nodes 23-25, the second input pins 27 of which are connected to the input terminals for connecting the first or second voltage of the mains supply. When the voltage stabilizes, the installed power of the three-phase transformer does not include the regulated power of the booster nodes, which are performed either on two transformers 10, 11 with biasing, or on one transformer with controllable keys in the primary circuit, 3 sludge.

one

The invention relates to electrical engineering and can be used in power supply circuits for electronic equipment.

The purpose of the invention is to reduce the installed capacity of transformer equipment.

Figs. 1 and 2 depict block diagrams of the electric circuit of the device with an output voltage of 220 and 380 V, respectively; FIG. 3 shows an example of the implementation of the electric circuit of the device when switching the primary windings of the booster assembly with ac semiconductor switches.

The device (Figs. 1 and 2) contains input terminals 1-3 for connecting the supply voltage 220 Bj, input terminals 4-6 for connecting the supply voltage 380 V and output terminals 7-9 for 220 V (FIG. , 1) or 380 V (Fig. 2), two booster transformers 10 and 11 in each phase of the lowering and boosting, respectively, with the secondary windings 12 and 13, the primary windings 14 and 15 of which are connected in series, and the first extreme leads connected to a star. The control windings 16 and 17 are connected to a control unit 18 connected to the output terminals 7-9. The introduced three-phase autotransformer 19 has taps 20 connected to input terminals for presses 1-3 of the corresponding phases with a voltage of 220 V, taps 21 connected to the input terminals of the corresponding phases 4-6 with a voltage of 380 V, and taps 22 connected to the second extreme leads Secondary installations 12 and 13. At the same time, the first extreme conclusions of the first

five

35

primary windings, booster transformers are connected to the input terminals of the respective phases 4-6 with a voltage of 380 V for stabilized. The first source shown in FIG. 1 and with the input terminals of the corresponding phases 1–3 with a voltage of 220 V dl of a stabilized source shown in FIG. 2, Transformers 10 and 11 form three booster nodes 23–25 included in each phase and having each input 26 and 27 and output 28 and 29 conclusions, and the same control inputs 30 and 31,

The device shown in FIG. 3 contains input terminals 1-3 for connecting the supply voltage of 220 V, input terminals 4-6 for connecting the supply voltage of 380 V to the supply voltage and output terminals 7-9 for voltage 220 B, voltoDaid transformer 10, having secondary windings 32, two primary windings 33

25 and 34, which are connected in series, and the winding 32 provides, when connected to the supply network through the key on the thyristors 35 and 36, work on the volt-residue, and the winding

30 34 when it is connected to the mains through the key on the thyristors 37 and 38 - the mode of operation of the booster transformer for the booster. The common points of the thyristor switches are connected to the input terminals 4-6, and the common points of the primary windings of the three-phase booster transformers are connected to the star (or to the input terminals as shown by the dashed line). The control inputs of the thyristor switches are connected to the control unit 18. Three-phase autotransformer 19 has taps 20, connected 40

20

25

The terminals 21 are connected to the input terminals of the respective phases 4-6 with a voltage of 380 V, and the taps 22 are connected to the terminals of the secondary windings 32. The transformers 10 form three volt-wiring nodes 23-25 with the input voltages 26 and 27 and output 28 and 29 outputs, as well as control inputs Q 30 and 31,

The device shown in figure 1, works as follows.

When the supply voltage of 380 V is applied to the input terminals 4-6, it 5 is supplied to the taps 2-1 of the transformer 19 and to the series-connected 1 | primary windings 14 and 15 of the step-down and step-up 11 volt-collecting transformers. From the taps 21 of the autotransformer 19, the voltage is removed, which is supplied to the second extreme terminals of the series-connected secondary windings 12 and 13 of the booster transformers 10 and 11.

The operation of the device can be considered in two extreme modes, for example, for a range of compensable changes + 10% and -20% of nominal. When the voltage of the network is 1.1 and "(, d (418 V) from the control unit 18, the control windings 16 are energized and the transformer rod is saturated. In this case, the voltage on its working windings is practically absent due to low magnetic permeability compared with the unsaturated transformer rod 10. In this case, only the step-down transformer 10 operates. When the network voltage is 0.8 and o (304 V), the control winding 17 receives power from the control winding 17, the transformer stem 10 is saturated and the transformation occurs stress .

The number of turns of the windings 12, 14 and 13, 15 booster transformers 10 and 11, as well as the windings of the autotransformer 19 are selected from two basic conditions: so that at any of the two extreme values of the supply voltage, the nominal voltage of the terminals 7-9 is removed and achieved approximate power equality

thirty

40

45

50

The transformers 10 and 11 are controlled by the control unit 18 so that the output maintains a voltage equal to the nominal. Operation of the device when supplying an input voltage of 220 V is similar. It is also possible to connect the primary windings 14 and 15 to the taps 20 or 21, however, in this case, the power of the auto formator 19 must be increased.

The operation of the device shown in FIG. 2 is similar, only the voltage of 380 V is removed from the output pins.

The device of FIG. 3 operates in analogy to a three-phase stabilized voltage source of FIG. 1, only the voltage regulation is both baked by switching the primary windings 33 and 34 of the booster transformer 10 using semiconductor alternating current keys on the thyristors 35, 36 and 37, 38 from the control unit 18. In the device of FIG. 3 it is possible not only the algorithm of operation of the thyristor keys of the voltage-deduction mode for the voltage boost, but also the reverse, as well as multiple pulse-width adjustment is possible, however, in this case, artificial switching or fully controlled semiconductor keys should be used, for example, the transistor included in the diagonal of the diode bridge.

The technical and economic G-1eska efficiency of the technical solution is as follows.

Thus, regulation does not imply total power, but only a part of it, determined by the range of compensated changes in the input voltage, but the main part during a 380/220 or 220/380 V transition is converted by a conventional transformer. When the voltage is stabilized, the installed power of a three-phase transformer does not include the regulated power of booster transformers. The devices achieve an approximate equality of the installed power in the extreme modes of the volt-deduction and the voltage of the additive; therefore, it is close to optimal use.

booster transformers. At55 additional booster transformers.

Claims (1)

Invention Formula input voltage is 0.8 U. I and 1.1 and the ratio between the transformation intervals of the voltage booster, a three-phase stabilized source of alternating voltage, with 0 five 0 0 five 0 The transformers 10 and 11 are controlled by the control unit 18 so that the output maintains a voltage equal to the nominal. The operation of the device when applying the input voltage of 220 V is similar. It is also possible to connect the primary windings 14 and 15 to the taps 20 or 21, however, in this case the power of the autotransformer 19 must be increased. The operation of the device shown in FIG. 2 is similar, the voltage of 380 V is removed only from the output terminals. The device of FIG. 3 works similarly to a three-phase stabilized one. The voltage source of FIG. 1, only the voltage regulation is provided by switching the primary windings 33 and 34 of the booster transformer 10 using semiconductor alternating current keys on the thyristors 35, 36 and 37, 38 from the control unit 18. In the device of FIG. 3, it is possible not only the algorithm of operation of the thyristor keys of the voltage-residue mode for the voltage boost, but also the reverse, as well as multiple pulse-width regulation is possible, however, in this case, artificial switching or fully controlled semiconductor keys should be used, for example, the transistor included in the diagonal of the diode bridge. The technical economy of the G-1eska efficiency of the technical solution is as follows. Thus, not all power is regulated, but only a part of it, determined by the range of compensated changes in the input voltage, but the main part at a 380/220 or 220/380 V junction is converted by a conventional transformer. When the voltage is stabilized, the installed power of the three-phase transformer does not include the regulated power of the booster transformers. The devices achieve an approximate equality of the installed power in the extreme modes of the volt-residue and the volt additive; therefore, close to optimal use is ensured. 1, Three-phase stabilized source of alternating voltage, with