SU1472887A1 - Dc voltage stabilizer - Google Patents

Abstract

The invention relates to electrical engineering, in particular, to sources of secondary power supply. The purpose of the invention is to reduce output voltage ripple. The device contains a power transformer 1 with primary winding 2 and secondary windings 3-5, power rectifiers 6.7, auxiliary rectifiers 8, 10, conjugated with individual smoothing filters 9, 11, reference Zener diode 12, separation capacitor 13, choke smoothing filter 14 regulating the transistor 15. The device features consist in the constructive implementation of the node 18 for the formation of an additional alternating voltage, which is made on four-winding transformers 19, 20 with a loop capacitor 29, current The limiting resistor 30 and the filter plug consisting of a capacitor 31 and throttles 32. When the mains voltage deviates from the nominal value, the opening degree of the control transistor 15 accordingly changes. the increase / current through the control transistor 15 and the voltage across the load 37 remain unchanged. The capacitor 13 shifts the phase of the variable component of the current in the second of these circuits by an angle of ϕ / 2, and the node 18 operates in the mode of dividing the frequency by two. Due to this, the output voltage of the stabilizer is almost equal. 1 hp ff, 2 ill.

Description

winding 2 and secondary windings 3-5, power rectifiers 6, 7, auxiliary rectifiers 8, 10, coupled with individual smoothing filters 9, 11, reference statitel 12, separation capacitor 13, choke smoothing filter 14, regulating transistor 15 Features of the device consist in the constructive implementation of the node 18 for the formation of an additional alternating voltage, which is made on four-winding transformers 19, 20 with a loop capacitor 29, a current-limiting resistor 30 and a plug filter, In this case, when the mains voltage deviates from the nominal value, the opening degree of the control transistor 15 accordingly changes. As a result, the increase (decrease) of the current through the throttle smoothing filter 14 is compensated by lowering (increasing) the current through the regulating transistor 15 and the voltage at load 37 remains unchanged. The capacitor 13 shifts the phase of the variable component of the current in the second of these circuits by an angle, and the node 18 operates in the mode of dividing the frequency by two. Due to this, the output voltage of the stabilizer is almost equal. 2 Il.

one

The invention relates to electrical engineering, in particular, to sources of secondary power supply of automation, telemechanics and computer equipment.

The aim of the invention is to reduce the output voltage ripple.

Fig. 1 shows a circuit diagram of a DC voltage stabilizer; Fig. 5 shows signal timing diagrams illustrating the process of suppressing output voltage ripples.

The device contains a power transformer 1 with a primary winding 2, a first secondary winding 3, a second secondary winding 4 and a third secondary winding 5, the first power rectifier 6, the second power rectifier 7, the first auxiliary rectifier 8 with a smoothing filter 9 9 , a second auxiliary rectifier 10 with a smoothing filter 11, a reference zener diode 12, a coupling capacitor 13, a throttle filter 14 regulating the transistor 15 with resistors 16, 17 in the control circuit, an additional variable voltage forming unit 18 wiring with four-winding transformers 19 and 20, having primary windings 21 and 22,

the first secondary windings 23 and 24, the second secondary windings 25 and 26 and the third secondary windings 27 and 28, the loop capacitor 29, the current-limiting resistor 30 and the filter plug consisting of the capacitor 31 and Drossel 32. The diagram also shows the conclusions 33 and 34 for connecting the primary AC network, terminals 35 and 36 for connecting the load 37. The primary winding 2 of the power transformer 1 is connected to the terminals 33 and 34. The input of the power rectifier 6 is connected to the secondary winding 3 of the power transformer 1, and the output through the choke smoothing function ltr 14 - with terminals 35 and 36. The exciter input of the node 18 for the formation of an additional alternating voltage (primary windings 21 and 22 of transformers 19 and 20) is connected via an isolating capacitor 13 to the output of the power rectifier 6, and the output (secondary windings 27 and 28 of transformers 19 and 20) through the series-connected power rectifier 7 and collector-emitter junction of the regulating transistor 15 with terminals 35 and 36. The inputs of the auxiliary rectifiers 8 and 10 are connected respectively to the secondary windings 4 and 5 of the power transformer

1, and the outputs through individual smoothing filters 9 and 11 are connected to the opposite side of the control circuit of the control transistor 15. The reference zener diode 12 is connected parallel to the output of the smoothing filter 11.

In the node 18 for the formation of an additional alternating voltage, primary windings 21 and 22, secondary windings 23 and 24, 25 and 26, 27 and 28 -

transformers 19 and 20 are connected in pairs and in series. The secondary windings 23 and 24 are closed to the loop capacitor 29. The secondary windings 25 and 26 through the current limiting resistor 30 and the filter stopper 31, 32 are connected to the output of the power rectifier 6. The filter stopper 31, 32 is set to double frequency 2o (y - frequency in the primary AC network).

The device works as follows.

When applied to the primary winding 2 of the power transformer 1, the alternating voltages in the secondary windings 3, 4 and 5 induce EMFs rectified respectively by rectifier 6, 8 and 10. The rectified voltage from the output of the rectifier 6 through the throttle the smoothing filter 14 enters the load 37 and through the separation capacitor 13 is supplied to the primary windings 21 and 22 of the transformers 19 and 20 of the unit 18 for the formation of an additional alternating voltage. In the presence of a bias current flowing through the secondary windings 25 and 26 in the ferroresonant oscillatory circuit formed by the secondary windings 23, 24 and the loop capacitor 29, auto-parametric oscillations are excited in the frequency division mode by two. Consequently, if at the output of the power rectifier 6, the voltage U6 (Fig. 2a) has a frequency of 2co, then the voltage U7 at the output of the power rectifier 7 formed after dividing the voltage Ug at node 18 into two and two-wave rectifiers Mleni, also pulsates with a frequency of 2CO. By means of the separation capacitor 13, the phase shift of the voltage U7 is carried out by an angle

equal - (fig.26).

The value of the current flowing through the control transistor 15 is determined by the magnitude of the voltage of the primary network. As the mains voltage increases above the nominal value, the difference between the output voltage of the smoothing filter 9 and the reference voltage at the outputs of the zener diode 12 decreases, the base current of the control transistor decreases and the latter is under-closed. As a result, the increase in current through the choke smoothing filter 14 is compensated by the decrease in current through the control transistor 15 and the voltage

50

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five

five

U

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at load 37 remains unchanged. Similarly, the output voltage U BblX is stabilized with a decrease in the mains voltage, when a decrease in the current through the choke smoothing filter 14 is compensated by an increase in the current through the control transistor 15.

At the rated voltage of the primary network, the currents flowing through the throttle smoothing filter 14 and the regulating transistor are equal and the ripple in the output voltage is practically absent (Fig. 2c).

Claims (1)

Invention Formula A DC voltage regulator containing a power transformer, the primary winding of which is connected to the terminals for connecting the primary AC network, the first power rectifier whose input is connected to the first secondary winding of the power transformer, and the output through a choke smoothing filter to the outputs for connecting loads, a node for the formation of an additional alternating voltage, which excites the input through a coupling capacitor connected to the output of the first power rectifier, output through series-connected second power rectifier and collector-emitter junction of the regulating transistor with leads for connecting the load, the first and second auxiliary rectifiers, whose inputs are connected respectively to the second and third secondary windings of the power transformer, and the outputs through individual smoothing filters connected in opposite -consistent to the regulating transistor circuit, the reference zener diode, included parallel to the output of the smoothing filter related to the unlocking control transistor auxiliary rectifier differs from the fact that, in order to reduce the output voltage ripple, the additional alternating voltage generation unit is designed as two four-winding transformers, a loop capacitor , a current limiting resistor and a plug filter tuned to twice the frequency, the primary windings the mentioned transformers are connected in series and connected to the terminals of the exciting input of the node, the first secondary windings are connected in series with each other and with the loop capacitor, the second secondary windings are connected in series and through the current-limiting resistor and filter plug are connected to the output of the first power rectifier, and the third secondary windings connected in series and connected to the output views of the node. , g Ј Yy g 3-JT g tit C) iz.l