SU1325646A1 - Dc-to-ac converter - Google Patents

Abstract

The invention relates to a conversion technique. The purpose of the invention is to improve the switching resistance by providing the dynamic characteristics of the current source. The converter contains two valves 4 and 5 and a switching capacitor 3 connected to the primary winding of the transformer 2. The primary windings of the current transformer are connected to the anodes of the valves 4 and 5, and its secondary winding is connected in series with the load 6. With a discontinuous change of load down to short circuit. the current in the load circuit is limited and proportional to the input current of the inverter, the rate of change of which is limited by the inductance of the choke 1. 1 Cp. f-crystals, 4 Il. i (L th go SP Od 4: Od Figure 1

Description

The invention relates to electrical engineering, in particular, to direct current converters to transformers, and can be used in the construction of autonomous power sources operating at fast alternating loads (for example, electrotechnological load), as well as in the construction of sources of guaranteed electrical power.

The aim of the invention is to improve the switching resistance by providing the dynamic characteristics of the current source.

Figure 1 shows the current-to-variable converter circuit; Fig. 2 illustrates a converter circuit allowing the current to be divided with a given proportionality in the branch x of a branch load; on fig.ZiA- variants of the circuit converters, made on the basis of the bridge valve kit.

The DC / AC converter (Fig. 1) contains a primary winding of the output transformer 2 connected via an input choke 1 to one power output by a midpoint, to which two switching capacitors 3 and two valves (thyristor) 4 and 5 are connected The secondary winding of the transformer 2 is connected to the load circuit 6, and the current transformer 7, the two primary windings of which are connected by opposite terminals to the anodes of the valves and to the outer terminals of the primary winding, are connected by the secondary winding after successive load 6.

The thyristor control is transformed according to the scheme of FIG. 1 is similar to the control of the thyristors of a conventional parallel current inverter and consists in alternately applying pulses to the control electrodes of the thyristors A or 5. Moreover, since the load circuit is connected to the circuit of the inverted current by means of the current transformer 7, even with a discontinuous change loads up to a short circuit, the current in the load circuit is limited and proportional to the input current of the inverter, the rate of change of which is limited by the inductance of the throttle. This determines your switching stability ness invariant vertora and equivalence of its dynamic characteristics characteristic exterior power source. The Rplgay transformation ratio of the current transformer 7, the more rigid the current characteristics of the transformer tel.

In the converter shown in FIG. 2, the number of current transformers 7 is equal to the number of load branches 6 and the number of secondary windings of the output transformer 2.

The operation of the circuit of FIG. 2 is similar to the operation of the circuit of FIG. 1 with the difference that the currents in the load branches are determined by the ratios between the transformation ratios of the transformers 7 and do not depend on the ratio of the parameters of the load branches not only in the speakers, but also in stationary modes. In the particular case, if T5se, the transformation ratios are the same, then the currents in the branch x of the load are the same.

Figs 3 and 4 show two of the possible modifications of the converter, having the same advantages as the circuits of Fig. 1 and Fig. 2, but made on the basis of bridge valve kits with additional gates 8 and 9. The control of the thyristors of the figs , 3 and 4 are similar to the control of the thyristors of a conventional bridge inverter and consist in alternately applying control pulses simultaneously for a pair of crosswise lying thyristors.

The high switching stability of the converters, the improved dynamic characteristics are explained by the presence of transformers in the converter circuits with a sufficiently large transformation coefficient. Thus, for example, the time provided for the restoration of the thyristors of the switch in the circuit of FIG. 1 is determined by the coupling

t

CCS

boss. 4f

de f

four

. WITH

to

tr

converter output frequency;

load resistance; switching capacitor capacity;

CoE () transformer transformation factor 8.

Kz of this expression shows that the greater the smaller the influence of the load resistance on the recovery time13256464

The extreme leads of the primary winding of the output transformer, and in series with the load circuit, the secondary winding of the current transformer is connected.

, DC-to-AC converter, containing a midpoint connected through an input choke to a single supply terminal

laziness, the closer this time to the maximum allowable equal to l / 4f.

Claims (2)

Invention Formula 2. The converter according to claim 1, which is characterized by the fact that, in order to expand the functional winding of the output transformer by ensuring the division of the matrix, the two extreme terminals of which are connected in an extensive load circuit with a given proportionality, the collider, and two valves, the combined number of additional transformer-cathodes of which are connected to another P ° of the current and the second windings of the output-supply terminal, and the secondary winding of the transformer the connection of the branch is a branch of a potentially branched into a load circuit, distinguishing between load chains, and in accordance with the fact that, with the aim of improving the required proportionality of dividing the switching stability of the pu and current in the load circuit dynamic characteristics are the transformation coefficients of the stresses of the current source, it is equipped with current transformers, the corresponding current transformer, the two primary primary windings of which the windings of which are connected differently according to GOVERNMENTAL do vgaodami anodes with valves and with themselves. 79 75 FIG. Editor G. Gerber Compiled by A. Ruhman Tehred L. Serdyukova Proofreader E. Roshko Order 3122/53 : Circulation 659 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 FIG.