SU1403035A1 - Pulsed d.c. voltage stabilizer - Google Patents

Abstract

The invention relates to the secondary power supply sources of electronic equipment. The aim of the invention is to improve functional reliability by ensuring a reliable launch. A push-pull magnet-transistor switch made on power transistors 1 and 2 and current transformer 4 is turned on by the input terminal and the input of the DLC filter 9. The control of this key is carried out from the master oscillator 12. The winding 15 of the transformer 3 master oscillator 12 through the diagonal of the variable the current on the diodes 5, 6, 7 and 8 is connected in series with the winding 16 of the current transformer 4. The diagonal of the direct current of the diode bridge on the diodes 5, 6, 7 and 8 is shunted by a transistor 22, the control signal of which is formed one-time rum 11 at a signal latitude im. pulse modulator 10. When switched on, the diagonal of the direct current of the diode bridge is shunted through the diode 23 and the load resistance, which ensures a reliable start of the pulse-stabilizer. 4 ID with S (/)

Description

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The invention relates to electrical engineering and can be used in secondary power sources of electronic equipment.

The aim of the invention is to increase the functional reliability by ensuring a reliable launch,

Fig. 1 is a schematic diagram of a DC voltage regulator; FIG. 2 is a single-shot circuit; FIG. 3 is a modulator circuit; Fig. 4 shows voltage plots explaining the operation of the device.

The DC voltage regulator of FIG. I contains regulating transistors J and 2, transformers 3 and 4, four diodes 5, 6, 7 and 8, connected in a bridge circuit, DLC filter 9, pulse width modulator JO, one-shot 1 The driving voltage generator is rectangular in shape, the output of which is connected to the winding 13 of the transformer 3, the winding 14 of which is connected to the clock input of the pulse-width modulator 10, and the winding 15 is connected via a serially connected winding 16 of the transformer 4 to the diagonal ac current I diode bridge diodes 5, 6, 7 and 8; the negative terminal of the diagonal of the constant-i current of which is connected to the common cable. The windings 17 and 18 of the transformer 4 are connected respectively to the emitter junctions of the control transistors 1 and 2, the collectors of which are connected to the stabilizer input through the windings 19 and 20 of the transformer 4. The common point of the emitters of control transistors I and 2 is connected to the input of the DLC filter 9, the output of which is connected to the output terminal of the stabilizer and the input of the pulse-width modulator 10, the second input of which is connected to the common bus and the output to the single-voltage input 11 connected to the output terminal of the stabilizer and the common bus. In addition, the stabilizer contains a resistor 21, a transistor 22 and a diode 23, the cathode of which is connected to the output terminal of the stabilizer, the anode to the common connection point of the collector of the transistor 22 And the positive DC output diagonal of the diode bridge, the negative terminal of which is connected to. The emitter of the transistor is 22, and its base

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through a resistor 21 is connected to the output of the one-shot 1I.

The one-shot 11 (figure 2) contains a comparator 24, resistors 25-29, diodes 30 and 31 and capacitors 32 and 33.

Pulse width modulator 10 (FIG. 3). contains an operational amplifier 34, a sawtooth generator on resistors 35 and 36, diodes 37-40, capacitor 41, linear voltage divider on resistors 42 and 43, nonlinear voltage divider on resistor 44 and zener diode 45..

The BSC filter 9 is a series-connected choke and capacitor, in parallel with which a diode is connected.

Impulse Stabilizer Constant n. Voltage as follows.

The pulse width modulator 10 provides a low voltage at the output, and when the voltage reaches a predetermined level at its input, it generates a high level pulse at the beginning of each half-period, the voltage coming from the winding 14, and the pulse duration increases with a further increase in voltage inlet CMM.

The single-vibration 11 generates a high voltage at its output at zero voltage at the PWM output, and when the first short pulse appears from PWM 10 it generates a low voltage, and at the time of termination of each pulse at the BAT output 10 a short voltage is generated at the output of the single-oscillator 11 pulse of a high level, the duration of which is no longer dependent on the duration of the output pulse, but with a PWM of 10.

When voltage is applied to the input of the stabilizer and the master oscillator 12 on the winding 13 of the transformer 3 along-in. The alternating voltage of the form of the square wave is transformed into windings 14 and 13. At the same time, at the output of the stabilizer, as well as at the outputs of the IMM 10 and the single-oscillator 11, the voltage is zero. The transistor 22 is closed and the diagonal of the direct current of the diode bridge through the diode 23 and the output of the stabilizer is shorted. The AC voltage from the SWITCH 15 is supplied to the winding 16 of the transformer 4 and, transformed into the windings 17 and 18, alternately 314

Transistors 1 and 2 rarely open. Switching windings I9 and 20 in series with collectors of these transistors provides proportional current control, i.e. when the transistors are turned on, the windings 19 and 20 play the role of the primary windings and the energy for controlling the transistors and 2 comes from the collector circuit with the help of these windings. The master oscillator 12 does not give up current at this time, since a voltage is induced on the winding 16, directed against the voltage of the winding 15 of the transformer 3.

Switching the transistors} and 2 occurs at the moment of polarity change on the winding 15, while its voltage is applied to the winding 16 and there is an active locking of the currently open regulating transistor and unlocking after this other.

The alternate opening of the transistors leads to an increase in the output voltage of the stabilizer, which simultaneously feeds the one-shot circuit J). When the voltage reaches

by increasing the output voltage of the stabilizer, the width of the pulses is softened, and consequently, the instant of occurrence of a short positive pulse at the output of the one-oscillator 11 and the short-term opening of the transistor 22, changes

The fact that at the beginning of each half-period at the output of the one-oscillator I1 the voltage is zero, provides a locked state of the transistor 22. In this case, the voltage on the winding 15 of the transformer 3 is compensated through the open diode 23 by the voltage at the output of the stabilizer and winding 16 of transformer 4 is applied the difference of these voltages is equal to zero. As a result, at the beginning of each half cycle, transistors 1 and 2 are closed.

At the moment when the pulse terminates at the output of PWM 10 at the output of the single vibrator M, a short positive pulse is generated that unlocks the transistor 22, while the voltage from the transformer 3 is applied to the winding 16 and the voltage across the winding 15 of the transistor 1 or 2 is applied, after what is open

nor the minimum necessary for the working state of transistors 1 or 2

A single-shot (usually it is for operational amplifiers 10-20% of the nominal voltage), a high level voltage is generated at its output (see the description of the single-oscillator H operation below). The transistor 22 opens, the diode 23 closes and the alternating voltage from the winding J 5 through the diode bridge is now applied to the winding of the transformer 4 through the open transistor 22. The output voltage continues to increase. Thus, in contrast to the prototype, a reliable start-up of the proposed pulse voltage stabilizer is ensured.

When the output voltage of the stabilizer reaches a predetermined level, a narrow high-level pulses appear at the beginning of each half-period at the output of the PWM 10 (Figure 4). When a first such pulse appears, a low level voltage is generated at the output of the one-oscillator 11 and the transistor 22 closes, after which the output of the one-oscillator 11 shows short high-level pulses at the moment the positive pulse ends at the PWM output 10, and then

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is maintained by the current transforming from the corresponding collector winding 19 or 20. At the same time, as at the time of start-up, the effective efficiency and low power consumption from the control circuit are preserved.

Connection The current transformer 4 to the winding 15 of the master oscillator 12 through the transistor 22 at the moments of switching on the control transistors, unlike the prototype in which this connection is made by the output circuits of the comparator and the single-oscillator, significantly increases the output power of the entire voltage regulator.

PWM 10 and one-shot 11 operate as follows (FIGS. 2,3 and 4).

When the voltage at the input of PWM 1 O is less than a predetermined level determined by the voltage of the stabilization of the Zener diode 45, a divider on the resistors 42 and 43 and the voltage of the saw generator applied to the resistor 35, the output of the PWM has a low voltage level close to to the potential of a common tire. The resistor 29 of the one-shot 1I through the diode 30 reduces the potential of the inverting input

“. Of the 24, which leads to the formation of a high voltage at the output of the comparator.

When the voltage at the IDiM 10 input reaches a predetermined level at the output of CMM 10, at the beginning of each half-period (the frequency is determined by the rectangular voltage of the winding 14), narrow high-level pulses are formed. With a further increase in the voltage at the input of the PWM (output voltage of the stabilizer), the pulse width increases.

When the first positive pulse from the NIM 10 output appears at the one-vibration input, the single-vibrator capacitor 33 1 is bridged to a high level through the diode 31, the diode 30 closes and the potential of the inverting input of the comparator 24 becomes voltage on its non-inverting input that This is achieved by selecting the values of the resistors 25, 26 and 27, 28. The constant time of the discharge of the codex torus 33 is such that when the pulses are output at the PWM output, the diode 30 is permanently closed. During the leading edge of the PWM Yu pulse, a high voltage level is applied to the inverter's inverter input through the capacitor 32, which confirms the state of the comparator 24. At the end of the pulse with PWM 10, the voltage across the comparator 24 PWM 10 It is applied to the resistor 28, lowering the potential of the inverting input of the comparator 24 at the time of its recharge, and at that time it forms a short pulse at the output of the single-oscillator 1I (the pulse duration is determined by the capacitance value of the capacitor 32).

Claims (1)

Invention Formula A DC pulse voltage regulator containing the first and 5 0 5 O 0 five five the second control transistors, the first and second transformers, four diodes connected by a bridge circuit, a BSC filter, a pulse-width modulator that drives a rectangular voltage generator, to the output of which the first winding of the first transformer is connected, the second winding of which is connected to the clock input of the tweeter modulator, the third winding of the first transformer is connected via a serially connected first winding of the second transformer to the diagonal of the alternating current of the diode bridge, mi The pin of the direct current diagonal of which is connected to the common bus, the second and third windings of the second transformer are connected to the base-emitter junctions of the first and second regulating Transistors, the collectors are connected through the fourth and fifth windings of the second transformer to the inputs, the common point The emitters of the control transistors are connected to the input of the DLC filter, the output of which is connected to the output terminal and the first input of the pulse-width modulator, the second input of which is connected. A common bus, and the output is connected to the input of a single vibrator, power leads connected to the output terminal and a common bus, characterized in that, in order to increase functional reliability by ensuring a reliable start, a resistor, a transistor and a fifth diode are inserted into it, the cathode of which is connected to the output terminal, the anode is connected to the common connection point of the collector of the transistor and the positive terminal of the diagonal of the direct current of the diode bridge s whose minus terminal is connected to the emitter of the transistor and its base is connected via a resistor Chen to the one-shot output. / - 25 27 ъ ihr Mr. W Z9 GB fr l phage. 2 figl