SU1757070A1 - Constant voltage converter - Google Patents

Description

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The invention relates to electrical engineering and can be used in secondary power supply systems in various industries.

A transistor inverter is known, which contains two half bridges, the arms of which include transistors, an output transformer with an additional winding, the primary winding of which is connected to common points of the half-bridge transistors, the main choke, the first output of which is connected to the positive terminal of the power source, and the second to one common terminal the junction point of the half bridge; and two additional circuits for forming a switching path of the transistors, consisting of three star-connected branches, the first of which contains a charge diode and connected by an external output to the common connection point of the transistors of the corresponding half-bridge, the second branch holds a shunt capacitor and is connected by an external output to another common point of connecting half-bridges, the third branch contains a discharge diode, and an auxiliary choke, and the additional winding of the output transformer is provided with a branch It points and connected between the external leads third branches additional circuits, and an auxiliary inductor connected between the tap of the mean

point additional winding of the output transformer and one of the conclusions of the main throttle.

Also known is a push-pull transistor inverter containing a half-bridge, the shoulders of which include transistor switches shunted by chains of series-connected capacitors and a diode, with the common connection point of the transistor switches connected to the common connection point of these capacitors and the load terminal.

However, in known inverters there are significant losses in the resistors and the power transistors are additionally loaded with the discharge current of the capacitors, which leads to a decrease in the efficiency and reliability of the inverter.

The aim of the invention is to increase efficiency and reliability by reducing the dynamic losses in the transistors and reducing the current load.

To a DC converter, made according to a half-bridge circuit of an inverter with transistors, the DC diagonal of which is connected to the input terminals, and the diagonal of the alternating current to the circuit of the output terminals, while

each of the series-connected transistors is bridged by a chain of a series-connected diode and a capacitor, a current transformer is introduced,

The primary winding of which is connected in series to the output terminal circuit, and the secondary winding is connected to the input of the input rectifier bridge, the output terminals of which are connected to the connection points of the capacitor and the diode of the indicated chains, respectively.

The drawing shows a circuit diagram of a DC / DC converter.

5 The converter, made according to the half-bridge circuit of the inverter, contains transistor switches 1 and 2, shunted by chains of series-connected capacitors 3 and 4, diodes 5 and 6.

0 common connection point 7 of transistor switches 1 and 2 is connected to the common connection point of capacitors 3 and 4 and the output of load 8, a current transformer 9, the primary winding 10 of which is connected sequentially to the load circuit 8, and the secondary winding 11 is connected to the rectifier bridge input 12, the output terminals of which are connected to common points 13 and 14 of the connection of capacitors 3 and 4 and diodes 5

0 and 6 chains shunt transistor switches 1 and 2. In addition, the device contains capacitors 15 and 16 of the capacitive divider.

Constant voltage converter 5 operates as follows.

In the initial state, capacitors 3 and 4 are discharged. When the transistor switch 1 is turned on, the voltage of the capacitor 15 is applied to the load 8, the load current

0 through the current transformer 9 and the rectification bridge 12 charges the capacitor 4 to the sum of the voltages on the capacitor 16 and the load 8, i.e. to the input voltage level of the converter. In this case, the condenser 5 of the chain, the shunting open key 1, is not charged.

After switching off the key 1, the voltage on it starts to increase smoothly as the capacitor discharges due to the EMF of self-induction of the load circuit from zero to the value of the input voltage. This achieves a time shift of the current and voltage front on key 1, which leads to a decrease in the dynamic losses in it. With

5 on and off key 2, similar processes occur.

Claims (1)

Claims of the Inverter DC voltage converter, made according to a half bridge inverter circuit on transistors, diagonal five . . 1757Q7Q. .-, ..6. the direct current of which is connected to the kstor and reduce their current load, input pins, and the diagonal of the variable-current transformer, the primary of the current-to the circuit output pins, while the winding is enabled in series each of the series output terminals, and the second winding transistors are shunted by a chain of 5 connected to the input of an inputted rectifier connected in series diode and terminal circuit, the output pins of which A capacitor, characterized in that, are connected to the junction points by a capacitor to increase the efficiency and reliability by means of a generator and a diode of said chains corresponding to a decrease in dynamic losses in the transient.