SU1467720A1 - Bridge-type voltage converter - Google Patents

Abstract

The invention relates to the field of electrical engineering and can be used in secondary power sources with voltage conversion. The goal is to increase the KCD by eliminating through currents. The device contains transistors 3-6, the base-emter transitions of which, through the base resistors 7-10, are connected to the windings of the control transformer 2 and are bridged by series-connected first 15-18 and second 23-26 diodes and additional windings 27-30 - V-code transformer 1. During the time of current flow through additional windings 27-30 of output transformer 2 and transistors 3, 6 of the same diagonal occurs -, charge of capacitors 32, 33 through diodes 24, 25 in the second diagonal, and after current flow through will complement The coils of the transformer 2, the transistors of the 45th diagonal, are kept in the closed state by the voltage on the capacitor until the absorption process of the most inertial transistor is completed. 1 il. SS

Description

current 27-30 of the output transformer 1, and between the legs of the connection of the anode of each of the first diodes with resistors 19-22 and other winding terminals 27-30- included are condensers 31-34,

The transformer works as follows.

In describing the process, suppose that the dissipation time of transistor 3 is longer than the dissolution time of transistor 6. When applying a constant supply voltage E to the amplifier and an alternating rectangular control voltage to transformer 2, the transistors 3, 6 and 4, 5 alternately open and close, creating alternating rectangular voltage on the windings of the output transformer 1. When the polarity of the applied control signal is changed, the currents in the bases of transistors -3 and 6 change the direction, and the process will occur in the bases themselves. Excessive media storage. Transistors 3 and. b remain in saturation mode, and the polarity of the voltage on the windings of the output transformer does not change, with the result that currents do not flow in the bases of transistors 4 and 5; 28, diodes 17, 25 — winding 29; At the same time, the capacitors charge 32

The mechanism of elimination of asymmetries is as follows.

Suppose that transistor 3 is turned on and the duration of its included 25 state (taking into account the vanishing time) is longer than that of transistor 6,

As long as current flows in the windings 27 and 30, the capacitors 31 and 34 are charged to the amplitude value of the voltage

0 windings do not affect the operation of the inverter. After locking the transistor 6 into the transistor 3, the process of resorption of excess nosis occurs. a small increase in the collector voltage and a decrease in the voltage on the windings of transformer 1, if we consider that transformer 1 works on a rectifier with a capacitive filter, and

40 on the filter capacitor in the process of switching transistors does not practically change, then a small decrease in the voltage on the output winding of the transformer causes a sharp

45 reducing the current of the output rectifier. As soon as the voltage on the output winding decreases by an amount equal to the direct voltage of the output rectifier, the latter is locked by disconnecting the load circuit. Next transis50

the torus 3 closes and the core of the transformer 1 continues to re-magnetize in the original direction under the action of the energy of the capacitors

and 33 the voltages of the windings 28 and 29 are 55 and 34, discharging through resistors 19 and 22. The duration of this process depends on the magnitude of the current of the transformer at the moment of locking the transistors, t, e, proceeding of the transistor 6, ends and he locks up. The transistor 3 remains open, since its dissipation time is the following unbalance mechanism.

Suppose that transistor 3 is turned on and the duration of its on 5 state (taking into account the absorption time) is longer than that of transistor 6,

As long as current flows in the windings 27 and 30, the capacitors 31 and 34 are charged to the amplitude value of the voltage of these

0 windings and the operation of the inverter have no effect. After the transistor 6 is locked in transistor 3, the process of resorption of excess carriers occurs, accompanied by a small increase in the collector voltage and a decrease in the voltage on the windings of transformer 1, if we consider that transformer 1 works on a rectifier with a capacitive filter, and voltage 0 the capacitor filter is almost unchanged during the switching of transistors, then a small decrease in the voltage on the output winding of the transformer causes a sharp

5 decrease in the output rectifier current. As soon as the voltage on the output winding decreases by an amount equal to the direct voltage of the output rectifier, the latter is locked by disconnecting the load circuit. Next transis0

the torus 3 closes, and the core of the transformer 1 continues to re-magnetize in the original direction under the action of the energy of the capacitors

 and 34, discharging through resistors 19 and 22. The duration of this process depends on the magnitude of the transformer magnetizing current at the time of locking the transistors, t, e, originated 31А677204

the automatic balancing of the alternating current of the bridge, the shoulder of the converter, the DC gonal of which is connected to the input terminals, about the formula of the invention, in order to

 increase efficiency by eliminating the Squel Current Current Converter, an additional circuit connection containing in each of the arms of the output transformer, the base-emitter junction of the first diode through the basic resistor JQ, the inserted resistor is connected to the control winding the second diode, and the point co-format and shunted sequence of the first and second diodes,

directly connected to the first diode and included according to each other,

a circuit of the additional winding is output-through the injected capacitor of the transformer connection, connected in di- 15 with the emitter of the transistor.

Claims (1)

The claims g / . A bridge voltage converter containing a transistor in each arm, the base-emitter junction through which the base resistor is connected at | a bridge whose direct current diagonal is connected to the input terminals, which requires that, in order to increase the efficiency by eliminating through currents, the connection of an additional circuit windings of the output transformer with the first diode were implemented through an inserted resistor shunted by the second diode, and the connection point of the first and second diodes connected in accordance with each other is connected to the emitter of the transistor through the introduced capacitor.