SU1403306A1 - D.c. voltage converter - Google Patents

Abstract

The invention relates to the field of electrical engineering and m. used in drive powering devices. The goal is to expand the frequency range. The device is made under the bridge circuit on transistors 1-4. The output diagonal of the bridge circuit is connected through the output transformer 5 to the output terminals. An additional power supply 11 is connected to the zero bus and through resistors 12 and 13 to the windings of the feedback circuits connected via diodes 14 and 15 to the bases of transistors 1 and 2. The frequency of the converter increases in proportion to the voltage of the power supply. Supply voltage m. practically equal to the allowable voltage at the junctions of the transistors 1-4. 1 il.

Description

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I The invention relates to electrical engineering I and can be used in devices: for powering drives and as a magnetic modulation device.

The purpose of the invention is to expand the frequency range.

The drawing shows a schematic diagram of the device.

The Converter is made by the bridge circuit transistors 1-4. The output diagonal of the AC is connected to the output; to the new transformer 5, having the primary winding 6 and the winding of the feedback circuits 7 and 8, the first terminals of which are connected to the first diodes 9 and 10. Supplementary; The power supply source 11, connected: in anti-series with the main one, is connected to the zero bus and via resistors 12 and 13 to the first terminals of the windings of the circuit; feedback by second terminals: through diodes 14. and 15 with bases; transistors 1 and 2.

; The bases of the transistors 3 and 4 are connected by four; cut resistors 16 and 17 and diodes 9 and 10 with collectors in front.

 The device works as follows. When the supply voltage of the converter is larger than the voltage of the source 11, the device begins to generate output signals of the minimum frequency. At the moment of conduction,; for example, transistors 1 and 4, transistor 1 is opened by current flowing from a constant voltage source 11 through resistor 13, winding 7, diode 14, base-emitter junction of transistor 1, primary winding 6 and: junction collector-emitter junction of transistor 4,: since the voltage on windings 7 and 8 is equal to the voltage on the primary winding b, as containing the same number of turns with it. The transistor 2 is at this time closed by the voltage of the winding 8 connected in the direction covering the diode 15. Transistor 3 is closed, because the potential arriving at its base through resistor 16 is close to zero, and transistor 4 is open with current flowing at its base from constant voltage source 11. When the magnet transformer 5 is saturated, due to the influence of positive feedback zi pro

the opening of the transistors 2 and 3 and the closing of the transistors 1 and 4 proceed. When the magnetic circuit of the transformer 5 is reversed in the opposite direction, the described process repeats. The frequency of the output signals of the proposed generator increases in proportion to the voltage of the power source. At the same time, the current (and losses) in the control circuits practically does not change with increasing voltage of the power source, which allows the frequency of the output signals to vary over a wide range, bounded by the voltage of the source 11 and from above by the electrical strength of transistors and other schematic elements. In this case, the supply voltage can be almost equal to the allowable voltage at the transitions of the used transistors.

Claims (1)

Invention Formula A converter of constant voltage, made by the bridge circuit, in the circuit of the control transitions of the upper transistors of which the windings of the circuits are included feedback of the output transformer, the primary winding of which is connected to the diagonal terminals of the alternating current, while the DC diagonal is connected to the input terminals for connecting the main power source, and the bases of each of the lower transistors are connected to the collectors crosswise, characterized in that in order to expand the frequency range, an additional power source is inserted, connected in series with the main one, one of the terminals of which is connected to the first outputs via the input resistors Wires of the windings of the feedback circuits connected through the input first diodes, connected in accordance with the conduction direction of the lower transistors, with the diagonal leads of the alternating current, while the second conclusions of the windings of the feedback circuits are connected through the input second diodes to the base transistors, the turns of the windings of the feedback circuits and the primary windings of the output transformer are equal. 0