SU1328895A1 - Regulated voltage converter - Google Patents

Abstract

The invention relates to the field of electrical engineering and can be used in systems of secondary electrical brackets. The purpose of the invention is to increase the stability of the output eg. Converter - Two-stroke autogenerator on power transistors 1, 2 and transformer 3 with primary, output 4, additional 19 windings and winding 7 short. The control transistor 9 controls the state of the transistors 1 and 2 by shorter winding 7 using a pulse-width modulator 10, feedback circuit 11. Introducing additional winding 19, rectifier 20, capacitor 21, transistors 17 and 18, the differentiating chains 15, the trigger 14, the diode 12, and the resistor 13 provide an improvement in the shape of the output voltage by forcing the oscillator to start at the end of the pause. 1 il. WITH/)

Description

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The invention relates to the field of converter technology and can be used in secondary power supply systems for voltage conversion with galvanic isolation of input and output circuits and stabilization of the output voltage.

The purpose of the invention is to increase the stability of the output voltage by improving its shape.

The drawing is a schematic diagram of a stabilized voltage converter.

The converter contains a push-pull magnet-transistor oscillator on the power transistors 1 and 2 and the transformer 3c primary winding. The output winding 4 of the transformer 3 is connected via the main rectifier 5, the LC filter 6 to the load. The winding 7 is shorted to an auxiliary rectifier 8, parallel to the output of which the regulating key transistor 9 is turned on. The base of transistor 9 is connected to the output of bus-1) relative-pulse modulator 10, whose input is via a feedback circuit 11 to the output of the converter. The collector of transistor 9 is connected to the power bus of a pulse-width modulator through a series-connected diode 12 and resistor 13, to the connection point of which the counting input of the trigger 14 is connected. The trigger outputs are connected to the bases of the additional transistor switches 17 and 18 via the differentiating chains 15 and 16. An additional winding 19 with a terminal from the middle point is connected to an additional rectifier 20, to the output of which a capacitor 21 is connected. The power terminals of transistors 17 and 18 are connected in parallel to the diodes of the rectifier 20 respectively nno.

The Converter operates as follows.

When the supply voltage is turned on, the magneto-transistor generator is started. The base winding of the transformer 3 turns on the power transistors 1 and 2 alternately. As a result, a voltage appears at the output of the converter. When the last stabilization level, defined by feedback circuit 11, is reached, width-modulated pulses appear at the output of modulator 10. Open transistor

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9 creates a short circuit circuit of one of the semi-windings 7 through the diode.

This leads to the locking of the previously open power transistor and the breakdown of oscillations of the oscillator. The voltage across all the windings of the transformer 3 becomes zero. Power transistors 1 and 2 are closed.

At the end of the shorter pulse, the key transistor 9 closes, removing the short circuit of the winding 7. However, since there was no current in it, the electric mode of the winding 7 does not change and the next generator start can occur not earlier than the filter choke 6 is discharged. The life of the converter is unstabilized, with large pulsations.

In the proposed current converter, the mode of intermittent oscillations is completely excluded, which ensures high functional reliability of the device, regardless of the load power. This is done as follows. At the end of the short pulse, the transistor 9 is closed, the short-circuited mode of the winding 7 is removed. At the input of the trigger 14 appears im15

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voltage pulse, taken from the total

points of resistor 13 and diode 12. The latter is necessary in order to limit the amplitude of the input pulse of trigger 14 at the level of its supply voltage: if the voltage on the half-winding 7 exceeds the supply voltage, the diode 12 is closed, if vice versa, then closed the rectifier diodes Z.Proisho-. gives switching the state of the trigger 14. A positive pulse from one of its outputs is differentiated by a circuit 15 or 16 and opens for a short time one of the transistors 17 or 18. As a result, charged during a pulse from. the windings 19 through the rectifier 20, the capacitor 21 is connected to one of the half-windings 19. A voltage is applied to all the windings of the transformer, one of Si45 is opened

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Because of the effect of a positive feedback circuit, the auto-, generator starts up. Latitude-modulated pulses follow a strictly alternating polarity, since the flip-flop 14 turns on transistors 17 and 18 alternately, performing the function of frequency division.

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Claims (1)

To eliminate the influence of the parasitic formulas of the invention, the inductances of the dissipation of the windings to the Stabilized transformation of the short circuit mode of the voltage body containing the two-stroke primary winding and the short magnetic transistor auto-winding winding 7 of the transformer 3 voltage, the winding of which is shorter than the length of the half-wave rectifier A chain consisting of parallel-connected to a regulating transistor-connected diode and a capacitor lying, the control input of which of the control-emitter circuit of the regulator is connected to the output of the pulse-width modulator 9, to the achievement of the delivered modulator, the input connected to the target output It does not relate, but solves the task of the converter, which differs from the forced switching off of the transis- sion, so that, in order to reduce the stator 9 in the pause between the pulses of the modulation of the output voltage by means of a torus, providing a locking bias g uchscheni its form, administered dopolnn- of its control yuschem transition. The integral winding with the output of the average result reduces the time of the delay point, a rectifier on two diodes, a control signal that, in a capacitor, two additional transceivers, increases the resistance of the resistor, two differentiating control systems .20 trigger with a counting input , diode and Thus, a forced over and resistor, and the counting input of the trigger of the autogenerator at the end of the pair is connected via a resistor to the alarm, eliminates the ambiguity of the power supply trigger terminal and through the diode of the output voltage preryvistyhk collector voltage and the regulating transistors oscillation does not allow constituents osuschestvit25 P & additional winding with output stabilization of the output voltage of the middle point is connected through the outlet; entailing a significant magnifier on two diodes to the condensation of the variable component of the output, two additional transistors; voltage (ripple) when the rectifier is shunted by the diodes, and the use of the converter as a quality basis for each additional transistor of the converter, i.e. raises the stabilizer torus through the differentiating chain of the output voltage is transformed to the corresponding output of the trigger trigger with a counting input.