SU1453561A1 - D.c. voltage converter - Google Patents

Abstract

This invention relates to electrical engineering and can be used in secondary power supply sources. The goal is to increase reliability by reducing the switching time of the transistors while reducing the load power. The converter contains a transformer 1, transistors 2, 3, a control unit 4, a capacitor 5, a fixed delay circuit 6, 7, an additional capacitor 8, an alternating current switch 9, a current sensor 10, a threshold element 11. In full load mode, the alternating current switch 9 is closed , and additional capacitor 8 with capacitor 5 form a compensation circuit for inductance of transformer 1, which reduces the overload in transistors 2, 3. When the load power decreases, for example, to idle mode on command from the current sensor 10 through the threshold element nt 11 is turned off key AC 9 and decreases the capacitance value connected to the primary winding of the transformer 1, which reduces the rate of change of voltage across the transistors 2, 3 and therefore prevents transistor incorporation with a significant voltage at the collector at a fixed delay control signals. 1 il. i (L

Description

The invention relates to electrical engineering and can be used i sources of a secondary electric socketer of radio engineering, automatics and computer systems.

The purpose of the image is to increase the reliability of the constant 1 | 1 converter by reducing the speed 1 1 of changing the voltage on the transistor when the load power decreases.

The drawing shows a constant voltage converter circuit. A constant-voltage converter contains the transformer 1, the transistors 2 and 3, the control unit 4, the capacitor 5, the circuits 6 and 7 of the delay kHpoBaHHoft, the additional capacitor 8, the AC key 9, the current sensor 10 and the threshold element 11, with the outputs of control unit 4 being connected to the control inputs of transistors 2 and 3 via fixed delay circuits 6J and 7, and a capacitor 5 connected in parallel with the power transformer 1, with current sensor 10 being connected to the circuit about {valuable input inputs, control | th input key 9 variable t Single connected to the output 10 of the current sensor. the threshold element 11, and the additional capacitor 8 is connected n | a parallel to the capacitor 5 through an alternating current circuit 9.

The constant voltage converter operates as follows.

Let the load current be equal to the nominal value. In this case, a signal is inserted at the sensor, and the threshold element 11 turns on the alternating current switch 9, and the condensation-8 is connected in parallel to the capacitor 5. Let the total capacitance of the capacitors 5 and 8 be chosen from the maximal losses in the transistor piSx 2 and 3 when switching. When and the load current, especially in the mode close to the idle mode X () yes, the energy stored in the Transformer 1 is small, and the capacitors 5 and 8 may not be recharged to twice the power supply voltage All fixed delay that

leads to an increase in current through transistors 2 and 3, at the time of their inclusion. Therefore, when the load current decreases, the additional capacitor 8 is switched off by elements 9-11, decreasing the total capacitance. In this case, the air conditioner 5 has a value that provides the transistors 2 and 3 with minimal losses when they switch to the minimum power.

Thus, the introduction of the AC key and the threshold element 11 provides the transistors 2 and 3 with minimal losses over a wide range of loads, and, consequently, increases the reliability of the device in these modes.

Invention Formula

A DC converter containing a transformer, the secondary voltage of which is connected to the output terminals, and the extreme terminals of the primary winding - to the collectors of transistors, the emitters of which are connected to the first input terminal, and the bases are connected to the outputs of the control unit through fixed-delay circuits current, a capacitor connected between the outermost terminals of the transformer primary winding, an additional capacitor, the first terminal of which is connected to one of the extreme terminals of the primary winding of the transformer A transformer, characterized in that, in order to increase reliability by reducing the rate of voltage change in transistors while reducing the load power, a threshold element and an AC switch are connected between the second terminal of the additional capacitor and the other extreme terminal of the transformer primary winding, the middle terminal of which is connected via a current sensor to a second input terminal, while the current sensor is connected via a threshold element to the control input of an AC key.

Claims (1)

Claim A DC voltage converter containing a transformer, the secondary winding of which is connected to the output terminals, and the extreme conclusions of the primary winding are connected to transistor collectors, the emitters of which are connected to the first input terminal, and the bases are connected to the outputs of the control unit via fixed-delay circuits, a current sensor, a capacitor, included between the extreme terminals of the primary winding of the transformer, an additional capacitor, the first terminal of which is connected to one of the extreme terminals of the primary winding of the transformer a torus, characterized in that, in order to increase reliability by reducing the rate of change of voltage across the transistors while reducing the load power, a threshold element and an alternating current switch are introduced, connected between the second terminal of the additional capacitor and the other extreme terminal of the transformer primary winding, the middle terminal of which is connected through a current sensor with a second input terminal, wherein the output of the current sensor is connected via a threshold element to the control input of the AC key. Circulation 645 Subscription Custom polygr. ave, city of Uzhhorod, st. Project, 4