SU813627A1 - Ac-to-dc converter - Google Patents

Description

one

The invention relates to converter equipment and can be used to power various consumers.

An alternating current into constant current converter is known, which allows to simultaneously supply two loads 1 with full-wave voltage.

, The disadvantage of this converter is that it does not provide a high frequency ripple voltage at loads that are a multiple of twelve or six.

Known converters of alternating current to constant, made by zero circuits with taps from the secondary windings G2.

Their disadvantage is that they are intended only for step control, with one of the valve groups associated with the main terminals of the secondary windings that must necessarily be controlled.

Using these circuits, also, the ripple frequency cannot be obtained; it is equal to twelve in the case of a six-phase system of voltages, as well as the simultaneous powering of the voltage of the same magnitude of two loads.

An alternating current converter is also known to a constant current, consisting of two six-phase circuits with a balancing reactor, each of which is made on a separate transformer 3},

Such a converter, providing the possibility of supplying one of the loads with a voltage of twelve times the pulsation frequency and the other with a sixfold voltage, is complex because it contains two transformers and two equalization reactors.

The closest to the proposed is a converter made according to the scheme: two reverse stars with a balancing reactor Z.

The disadvantage of this converter is that it is impossible to supply two loads when receiving twelve clock pulses at one of them,

The purpose of the invention is to provide power to two loads, obtaining a six-pulse frequency for one of 0, twofold multiplication -; IH meadow and improving the use of secondary windings of the transformer.

This goal is achieved by the fact that in an AC-to-DC converter containing a transformer with two three-phase secondary windings connected to each other in two reverse stars, two rectifiers, each of which is connected to a corresponding secondary winding according to the zero scheme and a balancing reactor with the average output connected between the common points of the valves of both rectifiers, the average output of the surge reactor and the common points of the stars of the secondary windings form the output terminals provided with additional A large group of valves, and each of the secondary windings are made with a tap dividing its turns in the ratio (1-YT / Z): Uz /, 2, while the conclusions of the same-type power of the electrodes of the additional valves are combined and their common point forms an additional output the output, another output of the power electrode of one of the additional gates is connected to the middle output of the surge reactor, and each of the two terminals of the power electrodes of the remaining additional gates is connected to the secondary side of the corresponding winding.

FIG. 1 shows a converter circuit; in fig. 2 - diagrams of secondary phase voltages - e, rectified by the voltage of the x-drop U, valve currents i: Q.

The converter consists of a transformer containing secondary windings 1 and 2, connected according to the scheme: two reverse stars (primary windings in Fig. 1 are not shown), a surge reactor 3, valves 416. A load 17 is connected to the output terminals of the six-phase rectifier system, and a load 18 is connected to the output terminals of the twelve-phase system. The valve 16 is connected to the midpoint of the balancing reactor with an anode and cathode to a common point of the valves 10-15. From each phase of the secondary winding, a tap is made, which is connected to the anode of one of the ventilators 10-15. In this case, the turns into which the winding is divided into a tap are in the ratio (l-TT / S):. Thus, for example, a tap from phase a divides this winding in the ratio aa: ao (1-UZ / 2). (This ratio is derived from the condition of the amplitudes of the voltages of two six-phase systems: with a balancing reactor and systems with taps).

The power supply of the load 17 is carried out in accordance with the known principle of operation of the circuit with a balancing reactor from the secondary voltage system e, e, e, e, e (figure 2)

and voltages of the windings of the reactor 3. In addition, the voltage curve of the load and has a six-fold frequency of pulsations. Instantaneous values of stresses e, e, e, e,

4. phase coincidence with voltage

and ®fe ®c X ®V ®Z exceed at individual intervals equal to 30 electrical degrees. The instantaneous values of the voltage of a six-phase system with a balancing reactor (for example, e at the interval exceeds the voltage generated by the EMF of the reactor windings in conjunction with the EMF e and eg, e and e).

At other intervals, also equal to 30 el.grad (for example), the voltage of the six-phase system created by the secondary windings and windings of the equalizing rector exceeds the voltage of the tap e and ejj. load 18 in FIG. 2 shows the curve U (j, Thus the valves 4-9 work for 120 degrees., And within 30 degrees., For both loads 17 and 18 each. Valves 10-15 work for 30 degrees. each (Fig. 2, and only for the load 18. The valve 16 conducts over a period of sinusoidal voltage for 180 electr. because it is locked during the operation of the valves 10-15. On the load 18, a twelve pulse pulse is formed It should be noted that the current through the load 17 should not be less than the critical one, which is determined, as is known, by magnetizing yuschim current reactor 3.

Thus, the proposed device allows for the simultaneous powering of two loads, one of which with a twelve-pulse voltage from one group of transformer secondary windings

Claims (3)

1. USSR author's certificate number 529530, cl. H 02 M 7/12, 1977. 2.Ivanchuk B.N. and others. Thyristor and magnetic voltage regulators. M., 1968. 3. Kaganov I.L. Electronic and ionic converters, h. Sh. Mgl., SEI, 1956,   Y t ten e, yd fafteg jcd (a   // v / .. 1 i V ii at LU AiA / 537 W W V "eight. Have