SU1654799A1 - Method of control over push-pull 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 the quality of output voltage stabilization while expanding the control range. The key control signal 4 and 5, depending on the magnitude of the input voltage, either provides an interval in which both keys are turned on, or an interval in which both keys are turned off. These signals are formed by comparing the constant-voltage and saw-shaped voltage with the zero-organ 16, the voltage of the saw-shaped form being shifted in phase relative to the voltage of the divider 13. Depending on whether the duration of the signal on the zero-output 16 is half the period the frequency of the master oscillator 12, is formed either the interval in which the keys 4 and 5 are simultaneously turned on, or the interval when they are simultaneously turned off. 1 hp f-ly, 3 ill. y 82 P with S (L oe ate 4 J CO with # /. /

Description

The invention relates to electrical radio engineering, namely to power sources, and can be used in power supply systems of automation devices and computer technology.

The purpose of the invention is to improve the quality of the output voltage stabilization while expanding the range of regulation.

Fig. 1 is a diagram of a two-stroke voltage regulator that implements a control method; Fig. 2 shows timing diagrams explaining the operation of the stabilizer; in FIG. 3 a part of the scheme of a push-pull stabilizer with an example of possible executions of control units

The method of controlling a push-pull voltage regulator consists in comparing a sawtooth signal having a clock frequency with a DC signal, one of which is a reference signal, the other is proportional to the input or output voltage of a stabilizer, and the effect of the resulting signal the signal to the operating mode of the power switches, the sawtooth signal is shifted in phase from the clock signal, and the indicated resultant signal of the comparison of the said signal is sawn braznoy shape and DC signal depending on the moment of equality of these signals in the initial or final part of the sawtooth signal is used for simultaneously switching on or off of power switches, wherein bounda- Tsey mode is the end of each clock signal.

The indicated shift of the sawtooth signal relative to the clock signal is performed depending on the magnitude of the input or output voltage.

The stabilizer (Fig. 1), which implements the method, contains input terminals 1 to which a power amplifier of stabilizer 3 connected to power switches 4 and 5 and power transformer 6 is connected via choke 2 At the output of transformer 6 and throttle 2 rectifying diodes 7 are turned on 9, the capacitor 10 and the output 11 o

The signal of the master oscillator 12 through the frequency divider 13 is supplied

0

0 5 o.

five

0

to the input of the control matching section 14 and the input circuits of the power switches 4 and 5, and also to the input of the matching section 15. To the other input of the coincidence unit 15, the output signal of the zero-body 16 is fed, to one input of which a sawtooth signal is supplied from the source 17, whose frequency is equal to the frequency of the clock signal, whose amplitude is proportional to U ..,.

RD

The signal from the source 18 of the reference voltage (DC signal) is supplied to the second input of the zero-body 16.

The output of the coincidence unit 15 is fed to the second input of the matching unit 14.

In this scheme, a constant phase shift of the sawtooth voltage signal from the clock signal, equal to 90 electrical degrees, is provided.

This is ensured by synchronizing the source 17 of the sawtooth signal at the same time from the master oscillator 12 and from the clock signal of the frequency divider 13.

In Figures 1 and 2, the following notation is adopted: Ub is the power supply voltage, the output signal of the master oscillator (SG); UTfLKT is a clock signal, UBVMO is a zero-input signal, Un is a sawtooth signal, U is a signal of a reference voltage source, Ugb) X4o is a zero-output signal, Uy (, UBX5 are input signals of power switches 4 and 5, 1 ) you are the output voltage of the stabilizer.

i

Consider two possible modes.

works of power keys of the stabilizer.

When the sawtooth signal Un in its final part becomes equal in magnitude to the signal of the reference voltage source U0, a signal is generated at the output of the null organ 16

you but This signal is applied to one input.

node 15, the second input of which receives a signal from generator 12. The output signal of node 15 coincidence is shown in Fig. 2, the signal with duration t (in the end part of the sawtooth signal is obtained with a positive signal, and the signal with duration t2 in the initial part Signal Piloob I

five

a different form is obtained with a negative signal U 3.

The output signal of the node 15 coincides with the duration t, it acts on the node 14 of the alignment, causing an increase in the open state of each power switch 4 and 5 by the time t, which causes these keys to be open part of the time at the same time.

The push-pull stabilizer is operating at this time in an output voltage increase mode.

As the voltage of the power source increases, the amplitude of the sawtooth signal increases, and the equality point of this signal to the signal of the voltage source moves to the left.

After this point moves to the initial part of the sawtooth signal (the boundary is the end of each clock signal and the clock.), The state of the coincidence node changes as the signal of the master oscillator 12 (Fig. 2) changes, resulting in the output signal of the joint unit 15 with a duration of I, will call through the node 14 of the negotiation the simultaneous closed state of the power switches 4 and 5 (intermittent current mode), for example, for the time t2, which will lead to a decrease in the Uabix stabilizer relative to U & x - i.e. a parametric stabilization of the output voltage about

To improve the accuracy of stabilization of the output voltage, it is possible to use negative feedback in the direction, the signal of which affects the sawtooth signal (source 17) or the direct current signal (reference source 18).

It is also possible to use the change in the phase shift of the sawtooth signal and the clock signal,

1654799

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This shift is, for example, depending on the magnitude of the input or output voltage.

FIG. 3 shows an example of the implementation of matching nodes 14 and a match of 15 using AND-NAND logic elements.

Claims (2)

Formula from the range 1 o A method of controlling a push-pull voltage regulator operating in voltage boosting or lowering modes and performed on power switches, which consists in comparing a sawtooth signal having a clock frequency with a DC signal, one of which is a reference signal, the other - a signal proportional to the magnitude of the input or output voltage, and the effect obtained by the resulting signal on the operating modes of the push-pull voltage regulator, characterized in that, in order to improve and the quality of stabilization of the output voltage when expanding the control range, the sawtooth signal is shifted in phase relative to the clock signal, and the resulting comparison signal from the sawtooth signal and the DC signal, depending on the moment of equality of these signals in the initial or final part of the sawtooth signal, is used to simultaneously turn on or off the power switches, with the mode boundary being the end of each clock signal. 2. The method according to claim 1, wherein the signal of the sawtooth shape is shifted relative to the clock signal depending on the magnitude of the input or output voltages. U zg f  V , : fcr P P P j UXLV-bvq L but P P P h 2L ABOUT and and, %  V one P P P V-bvq L P P P 2L ABOUT and t 1 HGCH1. 6