SU1035755A1 - Bridge-type converter of a.c. voltage to d.c. voltage - Google Patents

Abstract

1. BRIDGE VOLTAGE VOLTAGE CONVERTER CONSTANT with n -frequency connectors between each other consistently and topo-. logically form a regular closed G-cell with a number where, 3f ..., and valves connected to the Lur-cell gate bridge, whose AC leads are connected via lines to the G-face and the DC outputs are the outputs of the device , characterized in that, in order to reduce the output voltage ripple level, the outer section of the valve windings is equipped with two taps to which the initials Lz are connected and LL additional wired lines, the latter connected to the additionally inputted, Collected in the L - cheykovy valve bridge which MGO circuit DC connected in parallel uni-angles with the source bridge and together with it forms 2L.1- cheykovy A valve bridge.

Description

2, the converter according to claim 1, wherein, in order to double the frequency ratio of the output voltage ripple, each input is equal to the distance from the adjacent edge of the valve section region.

coils, moreover, with the number of turns (K) from the edge equal to O, 25 / cos in a relatively common number of turns of the section, where (is a half-period of the bending output voltage; is the multiplicity of the pulsation frequency.

., 1 The invention relates to electrical engineering,. in particular, to converter equipment, and can be used as a source of direct current power supply with a higher frequency rate. Three-phase alternating current bridge converters with a P-frequency pulsation frequency are known, containing a three-phase power transformer equipped with one main (central) secondary (circuit) winding connected in a star, and a number of additional and additional connected to its free ends. auxiliary sections of circuit windings with taps. Topologically, the connected windings form an open polygon to which an L-gate bridge is connected by means of L lines. Its direct current output is the output of the converter. An advantage of the known converters is the possibility of constructing a circuit structure on one three-phase transformer that provides theoretically any frequency ratio of C 13- pulsation (J3) However, a decrease in level and an increased frequency of pulsation is achieved by introducing a large number of auxiliary windings and taps from them with a large variety of numbers of turns. , which significantly complicates the design and construction of the transducers and is their significant drawback. The drawbacks also include a large number of turns in power (circuit) windings, due to the fact that for large values of P, the center has three (1) as a winding, it duplicates the remaining parts of the windings that are topologically connected parallel to the main one, which is therefore almost unnecessary, and, as a result, consumption of active materials (copper, steel, aluminum, etc.) in such a dominant in weight and dimensions functional device converters, which is a power transformer; the complexity of circuit connections, design and manufacturing technology; significantly reduced (in relation to the theoretically expected) frequency. Output voltage ripple and its increased level due to strong asymmetry, leading to an increase in the mass and volume of the smoothing filters. The consequence of all is that the energy losses, the relatively low efficiency and reliability, and the increased cost are all increased. The closest to the proposed is a bridge converter of variables, voltages in constant with P | -fold pulsation frequency, containing M source sources of convertible EMFs, formed, for example, on the circuit windings of a converter transformer, electrical machine, which are interconnected in series consistently and topologically form a regular closed polygon (G-face) and gates assembled in L - a cell valve bridge, whose AC terminals are connected via lines to the G-socket, and the DC terminals are output terminals of the converter l c. A disadvantage of the known device is with a relatively small ir /) number of diagonal emfs generated by it, as a result, a relatively high level and a relatively low (equal to 5 (3 (1) 1g) frequency ratio of the variable component of the output voltage. the invention is to reduce the output voltage ripple level, as well as doubling its frequency. This goal is achieved by the fact that in a bridge converter voltage voltages are constant with a constant frequency pulsation containing the original sources of phase shift In the case of the number M, formed, for example, on transformer, autotransformer, electric mauiHhftt, phased generators, divided into sections, phased generators, which are interconnected in series and topologically, form a regular closed H-face with the number of faces, where, 3 ... and valves connected to an LC valve bridge, the AC terminals of which are connected - by means of lines to the H-junction box, and the DC outputs are device outputs each section of the winding sleepers It has two branches, to which the Yi of the source and additional input lines are connected, the latter being connected to the additionally introduced valves assembled into an L-valve bridge that is connected in parallel with the original bridge in parallel with the DC bridge and together with it forms a 2P cell valve bridge. In addition, each input tap is equidistant from the edge of the valve winding section nearest to it, moreover, with the number of turns K from the edge equal to 0.25 / cos Q relative to the total number of turns of the section, where (- is the period of the limiting output voltage; - the multiplicity of the pulsation frequency is shown in Fig. 1a, the diagram 8 is a cell bridge converter constructed on the basis of a faceted face, and Fig. 16 is the corresponding vector diagram of the formation of diagonal EMF forming the output voltage; Fig. 2 and 3 are implementation examples The TWA is constructed on the basis of 6- and 12-facets. The bridge transducer (Fig.T) contains M (2 initial sources of EMF variables that are phase-shifted relative to each other on the electrically EEG. (orthogonal). These orthogonal EMFs are formed on two circuit the windings 1 of the converter transformer (its network windings are not shown in Fig. 1) or the windings 1 of the electric machine .. Each of the two windings is divided into two sections: 2.1; 3.1; .one; 5.1, which, being interconnected in series, topologically form a regular closed Γ-face. Section 2.1; 3.1; .one; 5.1 each have two taps (2.2; 2.3; 3.2; 3.3; .2; .З; 5.2; 5.3), which are connected via L lines 6 () to L-cell valve bridges 7, k to outputs 8 and 9 of which Direct current, which is the output of the converter, is connected to a load of 10 .. In addition, each tap is made, in particular, with the number of turns from the edge of the corresponding section closest to the tap equal to D, 25 / cos Q of the total number of turns of the section, where, 5 - half period of the output voltage. The line T1 is connected to the anode of the valve 12, the cathode of the valve 13 is connected to the line I. The valves 15 and 1b enter the valve bridge 7. In FIG. 16 vectors 17.1-20.3 illustrate the operation of the device, which is performed as follows. Two source orthogonal | Each EMF divided into two sections and connected into a regular closed f-rpaHHHK (squared) form two diagonal EMF - vectors 17.1-19.1; 18.1-20.1 (. (- 1) - Vl «2). When these EMFs are in operation, a cell – valve gate bridge at its output generates a pulsating non-alternating voltage .1) with an amplitude Suqjfc equal to the modulus of the diagonal EMF vector 17.1-19.1. In this case, the frequency of the pulsation is P, NW - (- X), and its level is equal to YON (Un / nottc iMM + i Hummox j1-cb © K c0545rO, "3 relative to this level relative to the average value U of the output voltage U (ripple factor K) is Qtg (Q / 2)

32.5. The phase shift DSED is

When an 8-cell valve bridge is connected to the taps 2.2; 2,3l 3.2; 3.3; t.Z; “.3; 5.2; 5.3 of the circuit windings 1 on the load 10, a pulsating alternating alternating voltage Uja is formed by the new diagonal EMF - vectors 17.2-19.2; 18.3-20.3; 18.2-20.2; 19.3-17.3. These DEDS are phase-shifted relative to each other. A certain angle depends on the number of turns of taps relative to the total number of turns of the section. With an emf of amplitude and phase symmetry, this angle is equal to 2nd 2Г / П 2Г / 2Г 180Л +5 The amplitude of the output voltage U is equal within this angle to the modulus of the vector of the corresponding DEDS.

Each DSDS has a frequency that coincides with the frequency of the converted EMF, and is applied (Fig. 1a) between the anode of the corresponding valve of the cathode group of bridge 7 and the cathode of the valve of its anode group, let us take these valves belong to different valve cells.

The valves of these groups are opened, the DEDS of which is currently the greatest value. For example, at the time point corresponding to the action of vector 17.2-19.2, on the phase plane of the vector diagram (Fig. 16), the projecting power of the DEDS 17 -.- 219 .2 .

When the valves are open, a closed loop is formed to pass the current through the load, and on the remaining valves of bridge 7 a reverse polarity voltage is created (plus on the cathode and minus on the anode), due to which these valves turn out to be closed. DEDS, the value of which is currently the largest with respect to the outputs 8 and 9 of the converter. The current passage circuits and the elements contained in them cyclically change. In the considered circuit implementation of the device of such circuits for the period of any of the EMF (convertible or diagonal) eight. Their number determines the number of ripples of the output voltage over the period of the EMF (with amplitude-phase

DEDS symmetry - frequency rate of pulsation).

Using the vector diagram of FIG. 16 and / or the circuit of FIG. 1a, one can simply trace the paths of the load current along different circuits, find out their number, determine the shape of the currents and voltages on the circuit elements, including the vector and linear time diagrams of the output voltage. . So, for example, under the action of the DEDS of the vector 17.2-19.2, the current through the load-narrow 10 flows through the following loop (Fig. 1a): tap 2.2, line 11, valve 12, output 8, load TH, output 9, valve 13, line N , tap 4.2.

From branch k, 2, the load current branches out in two parallel, with equal resistance circuits, one of which contains part of section 4.1, section 5.1, part of section 2.1, the other part of section 4.1, section 3.1, part of 2.1.

Thus, due to the closed connection of the windings into a symmetric polygon, the current flowing through them is currently less than the load current, which is important at relatively high values of it. The equality of the resistances of parallel circuits (as opposed, for example, to the inequality of resistances in the connections of windings in a triangle), as well as a relatively small number of winding parts, their full sameness and simplicity of connection provide a higher ripple symmetry compared to the known converters (1-3) output voltage, improve the mass-dimensional and cost parameters of the smoothing filter and the manufacturability of the device.

After a time equal in angular units in / 2Г T / 8 22, 5 el. Degrees, the value of the diagonal emf of the vector 17.219 .2 becomes less than the value of the DEDS of the vector 18.3-20.3, and the valves 12 and 13 are closed, the valves 15 and 16 are opened. The load current passes through the circuit: drain 3.3 - valve 15 output 8 - load 10 - output 9 valve 16 - drain 5.3.

Further, the processes are repeated with a cyclic change in the circuits of the current passage and their associated windings and valves. As can be seen from FIG. 16, the number of diag- nostic emfs determining the frequency of the output voltage, is four (), which is two times more than in the prototype .. Accordingly, the multiplicity P of the pulse frequency also doubles (. The latter is achieved under the condition that the taps are equally removed from the adjacent edges of the sections, with the number of turns (k) equal to 0.25 / cos a 1 / (. Y2) o, 293 relative to the total number of turns of the section. This number of turns of taps is determined according to the sine vector theorem , of the triangle of Fig. 16. From this we obtain, 5. Therefore, (180/22 ,, which proves that Pulsation frequency: The pulsation level in the circuit implementation (Fig. 1a) is L Ir Ircos Q 1-COS 22,, 076, the pulsation coefficient K is 7.81, which is approximately k times less than the level of 0.293 and accordingly 32.5 % of the prototype. In this case, a positive effect is achieved without introducing a large number of additional and auxiliary windings of a power transformer with a significant variety of their number of turns, as is required in known devices. Consequently, with respect to the latter, with their inherent circuit design and technological complexity, and poor mass-dimensional indicators of smoothing filters due to the strong manifestation of low-frequency modulation of the output voltage, this technical solution is in all respects meaningful but simpler. With a different number of initial convertible emfs, lines and edges (M, L, g), circuit implementations of a bridge converter with a reduced level and a double pulsation frequency compared to the prototype are carried out with a similar method. FIG. 2a, topologically izob

There are transformer circuit structures in which sections of convertible EMF variables are connected, respectively, into 6- and 12-faces. Vector diagrams for them, showing .55 (like a diagram (Fig. 16), the formation of diagonal EMF in the phase plane, are given in Fig. 26, 36.

looking at the apparent percentage insignificance of such an increase, it is essential, especially in autonomous (for example, mobile objects) systems with a power of /; , commensurate with the power of the consumer, or in relatively powerful power systems. From FIGS. 2 and 3, it can be seen that the multiplicity of the pulsation frequency in these realizations with the number of turns of taps equal to 1 / (24- | Gz) 0.2b8 and 0.25, respectively, relative to the number of turns of the section is 12 and 2 , which is 2 times higher than in the prototype. The pulsation coefficient in either case is reduced by about a factor of k. The mass, volume, and cost of the smoothing filters installed in this case are reduced by a factor of one. For example, the design of the product LС required for designing an inductive-capacitive L-shaped filter is reduced by about (P / PL) or, for about 16 times, which is also an advantage of the device. In addition, increasing the frequency ratio of the pulsation improves the quality of the consumed and transported energy, reducing the level of unwanted harmonics in the output voltage and input current spectra. In particular, the shape of the latter in the presence of smoothing filters of an inductive nature (when a choke is installed as the first element of the filter in its longitudinal branch) approaches a sinusoidal one from a sharply stepped one. The sinusoidal form of current consumption is, as is known, the most advantageous for a predominantly sinusoidal form supply voltage, because it more simply reduces the level of network industrial interference and optimally provides the best distortion and power utilization the primary source of energy. For example, a valve converter with a 12-fold pulsation frequency and an inductive filter, based on a combination of two phase-shifted 6-phase circuits, has a power factor of about 0,, 958, against 0.88-0.915 for a converter with 6-fold pulsation frequency. Non-transfer from converters with a low frequency ratio of pulsation to converters with an increased frequency in some cases does not require an increase in capital investment, but leads to a decrease in operating costs. The economic efficiency of increasing the power factor is due to the reduction of losses in the energy supply system by reducing the reactive power fluxes, which is especially useful for the cViCTeM mentioned above. So, for example, the introduction of converters with a 12-fold pulsation frequency instead of converters with a 6-fold frequency at the railway substations of one of the Siberian regions provided, according to specialists, energy savings of about 500-600 MWh per year each of them, which is of crucial national importance, especially in the conditions of the emerging energy crisis.

Thus, in accordance with. The invention implements a bridge converter of alternating voltages into a constant, in which the output voltage ripple level is reduced, and its frequency doubled, which, as applied to the circuit structures of the valve power converters based on the circuit topological construction of the EBWS transformed according to the correct polyhedron, provides a solution important modern tasks in the field of power supply to improve the quality of transmitted and consumed energy, reduce the level of industrial interference .; . saving energy of primary sources, improving the MayO-overall indicators of smoothing filters and converter as a whole.

In this case, a positive effect is achieved without complicating the circuit topology of the connection of the sources of converted EMFs and, therefore, without the concomitant deterioration of the efficiency, reliability, mass and volume.

All this provides my converter with the appropriate technical and economic effect and practical utility of use;

 Mu, Hf (t2; Я-,, 25

ch.5

Claims (2)

<57) 1. A BRIDGE CONVERTER OF AC VARIABLE VOLTAGES TO CONSTANT with an η-fold frequency of pulsation, containing Mi source sources: $ a £ shifted. * EMF with number М _and т 1, formed, for example, on transformer valve windings divided into sections , autotransformer, electric machine, phased generators, which are interconnected in series and topo. logically form a regular closed Γ-facet with the number of faces — — 2k, where k = 2,3, ..., and В _M = 2 Г of valves connected to the Luryacheykovy valve bridge, the terminals of which are connected by alternating current through Л = Г lines to H-facets, and the DC outputs are the outputs of the device, characterized in that, in order to reduce the ripple level of the output voltage, each section of the valve windings is equipped with two taps, to which are connected Lts of the source and L = Additional input lines, the latter being connected to additionally In ennym ⁿ = 2Lts valves collected in K-Cellular valve bridge, which in the DC circuit is connected in parallel unipolarity · 'with source bridge and together with it forms an L * = 2N -yacheykovy valve bridge. * SU 1035755 2. The converter according to π. 1, characterized in that, in order to double the frequency of the ripple of the output voltage, each input-tap is equidistant from. the edge of the section of the valve coil adjacent to it, and with the number of turns (K) from the edge equal to 0.25 / cos & relative to the total number of turns of the section, where ОЯ / П is the half-period of the envelope of the output voltage; P = 2G = 2Pc - the frequency rate of the ripple.