SU824385A1 - Dc voltage-to-dc voltage converter - Google Patents

Description

(54) CONSTANT VOLTAGE CONVERTER TO PERMANENT

I

The invention relates to electrical engineering and can be used in power supply systems for converting low DC voltage to increased adjustable DC voltage.

Adjustable transformerless converters are known, containing capacitors switched by diodes and controllable switches from the parallel connection state, to the capacitors in their series connection with the regulation of the charge voltage of the capacitors 1.

The closest to the proposed technical entity is a DC / DC converter, which contains a diode bridge connected to one of the power supply lines in series with the load, two chains, each of which consists of a series-connected capacitor and a discharge switch connected with side of the capacitors to the diagonal of the bridge, .a from the side of the discharge switches to the same power bar, two charging switches connected between the points of connection of the capacitors with the discharge keys and the other pit no 2 ..

A disadvantage of the known device is low reliability due to the fact that there are through currents of short circuit of the power source during the Opening of the discharge key, if the charging key has not yet been closed. In addition, the charge current of the capacitors in the device is not limited, which leads to large current pulses from the power source and to a premature failure of key elements. Pulsed nature of the current consumed

from the power source, detects a high level of radio interference, which is also a disadvantage.

The purpose of the invention is to increase reliability.

The goal is achieved by the fact that

A DC-stabilizing element — a transistor — is additionally introduced into the DC-DC converter; its power electrodes are included in the charging switch circuit, and the base of which is connected to

Claims (2)

governing body. This makes it possible to eliminate the through currents of the short circuit of the power supply and limit the amplitude of the charge current of the capacitors, which greatly facilitates the operation of the keys. The drawing shows a DC / DC converter. A converter contains busses 1 and 2 connecting the power supply, a diode bridge 4–7 is connected in series with load 3 to a diode bridge 4–7. A capacitor is connected to the diagonal of the bridge — diodes 5 and 7 8, and a capacitor 9 is connected to diodes 4 and 6. The other terminals of capacitors 8 and 9 are connected, respectively, via bit 10 and 11 to bus 1, and through charging switches 12 and 13 to the current-stabilized emitter of its transistor 14, collector which through current measuring resistor 15 body 16, a control bus connected to two power. The base of the current-stabilized transistor 14 is connected to the control body 16. Control element 16 can be made, for example, in the form of a transistor 17 with a current-measuring resistor in the emitter circuit and a potentiometer in the base circuit. The Converter operates as follows. In one half cycle of the switching voltage, the keys 11, 12 are closed and the keys 10, 13 are open. The transistor 17 of the control body 16 and, consequently, the transistor 14 opens. The capacitor 8 is charged through the transistor 14 and the current-measuring resistor 15. The increase in the charging voltage current leads to an increase in the voltage drop across the resistor 15, which leads to the closing of the transistors 17 and 14. Closing the transistor 17 leads to a decrease in the charging current. Thus, the current is stabilized during the charging of the capacitor 8. The magnitude of the charging current is determined by the position of the potentiometer slider in the base circuit of transistor 17. Therefore, the capacitor 8 is charged to the voltage determined by control 16. In the other half cycle of the switching voltage, the keys 10, 13 are closed and the keys 11, 12 are open. As a result, the capacitor 8 is connected in series with the power source, therefore the voltage on the load 3 is equal to the sum of the voltage of the power source and the capacitor 8. Simultaneously through the current stabilizing transistor 14 and the key 13, the charge of the capacitor 9 occurs. By changing the control unit 16 of the value of the stabilizing charge current of the capacitors 8 and 9, the output voltage can be regulated in the converter within the voltage range power supply voltage to twice its value. The proposed device has increased reliability due to the elimination of "through currents and limiting the amplitude of the charge current of the capacitors. Claims of a DC / DC converter containing a diode bridge connected to one of the power lines in series with the load, two chains each of which consists of a series-connected capacitor and a discharge switch connected from the side of the capacitors to the diagonal of the bridge, and on the side of the bit switch to the same power bus, two charge keys connected to the junction points of capacitors and bit switches, characterized in that, in order to increase reliability, in it the charge keys for Connected to another power supply through the power electrodes of an additionally inserted current-stabilizing transistor, the base circuit of which is connected to the control. Sources of information taken into account during the examination 1. USSR Author's Certificate No. 571860, cl. H 02 M 3/18, 1976. 2. USSR author's certificate number 572882, cl. H 02 M 3/18, 1977. 0 YU rx: // -n 6 -K3-4 five 0 / 2 //. / 3 2 & / ( -4Z & / 5U