SU1390738A1 - D.c. voltage converter - Google Patents

Abstract

The invention relates to converter equipment and can be used in electrical engineering for powering REA with increased input voltages. - The purpose of the invention is to increase the reliability of the CDC by reducing the voltage on the transistor switches of the converter. The dc-to-dc converter contains two identical dc voltage regulators of different polarity, interconnected in series along the input and output. Regulators contain capacitors 1, 2 of the input filter, capacitors 3, 4 of the output filter, reverse diodes 5 and 6, windings 7 and 8 smoothing throttle 9, transistors 10 and 11i transformers 12 and 13 with windings 14,16,19 and 15,17 ,20, . control unit 18. By switching on the winding 19 of the transformer 12 of the first pulse regulator into the collector circuit of transistor 11, the second of the controller, and the winding 20 of the transformer 13 in series with the transistor Yu of the first pulse regulator, switching off and on of the transistors occurs simultaneously and thereby eliminates The main reason for the uneven division of the voltage of the power source between the pulse regulators is the spread of the parameters of the transistors. 3 il. l 00 so about 00 cx

Description

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The invention relates to converter equipment and can be used in the development of power supplies and electric drives.

The purpose of the invention is to increase the reliability and efficiency of the pre-explorer by reducing the power of the transistor to new keys.

Fig. 1 is a schematic of a converter of the reference type DC voltage converter; in fig. 2 - the same type; in fig. 3 - the same inverting type.

The converter contains the first impulse regulator of positive polarity and the second impulse regulator of negative polarity. - Each of the regulators, respectively, contains capacitors 1 and 2 of the input filters, capacitors 3 and 4 of the output filters, reverse diodes 5 and 6, magnetically coupled windings 7 and 8 smoothing droplets 9 output filters with an equal number of turns, transistor switches 10 and 11, transformers 12 and 13. Secondary windings 14 and 15 of transformers 12 and 13 are connected to the control transition of the transistors tO and 11 ,, secondary volts heel 16 and 17 - to the node 18 controlling third primary 19 of the transformer 12 of the first regulator is connected in series with the transistor switch 11 of the second controller and the third winding 20 of the transformer 13 - in series with a transistor switch 10 of the first regulator. A power source 21 is connected to the converter input, and a load 22 is connected to its output. In the control unit 18, the windings 16 and 17 of transformers 12 and 13 can be connected both in parallel and in series.

The Converter (figure 1) works as follows.

The control unit 18 detects voltage pulses of a certain frequency, the duration of which can be adjusted. These pulses arrive simultaneously at the windings 16 and 17 of transformers 12 and 13. Suppose that at the considered moment of time the polarity of the voltage corresponds to that shown in Fig. 1 without brackets. Such a polarity is unlocking for transistor switches 10 and 11. After the transition, the transistor

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Ditches 10 and 11 in the metric state reverse diodes 5 and 6 are closed. In the magnetic field of the throttle 9, an accumulation of electromagnetic energy occurs.

When fed from control unit 18, locking pulses, the polarity of which is shown in FIG. t in brackets, transistors 10 and 11 are closed. The throttle current 9 is closed through the reverse diodes 5 and 6, the capacitors 3 and 4, and the load 22. Since the number of turns of the windings 7 and 8 of the throttles 9 are the same, and the magnetic coupling between them is high, the voltage on them is equal, which leads to alignment voltages on capacitors 3 and 4 output filters. The next time the transistors 10 and 11 are turned on (the polarities of the voltages in Fig. 1 without brackets), the capacitors of the input filters 1 and 2 are connected to a circuit consisting respectively of winding 7 throttle 9 and capacitor 3 and winding 8 throttle 9 and capacitor 4. Since the voltages on the windings 7 and 8 of the throttles 9 remain the same, and the voltages on the capacitors 3 and 4 are equalized earlier, the voltages on the capacitors 1 and 2, i.e., they become equal to half the voltage of the converter power supply 21. Thus, with subsequent locking of the transistors 10 and 11 and unlocking the reverse diodes 5 and 6, the voltage on the first will be the same and equal to half the supply voltage.

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In the on state, the unlocking current of the base of the transistor. 10 is added up from the collector current of the transistor 11, transformed from the winding 19 to the winding 14 of the transformer 12, and from the current of the control unit 18 transformed from the winding 16 to the winding 14 of the same transformer. Accordingly, the unlocking base current of the transistor 11 is added up from the collector current of the transistor 10 and the current of the control unit 18, transformed into the winding 15 of the transformer 13. At the stage of locking the transistors, their base currents are equal to the difference of the indicated currents, as the current of the control unit 18 changes its direction. When node 1.8 of the control detects locking pulses (their polarity is

brackets), transistors 11 and 12 begin to close. Assume that in transistor 12, the resorption process is in laws, and the collector current begins to decrease. This will cause the blocking current of the base of the transistor 11 to increase and it will forcibly turn off. In this case, until the absorption process in the transistor 11 is completed, its collector current will prevent the output from the saturation of the transistor 10. Thanks to this mutual the influence of transistors on each other, the decline of the collector currents occurs almost simultaneously and the over-discharge of capacitors 1 and 2 does not occur, i.e. the voltage across them remains equal to half the voltage of the converter power supply. Similarly, it can be shown that when the transistors are turned on, their collector currents change in the same way and the voltage division on the capacitors 1 and 2 is not disturbed.

Of particular note is the advantage of the converter that the voltage dividing equilibrium is maintained, both when using in parallel control unit 18 a parallel connection of the windings 16 and 17 of transformers 12 and 13, and of a series one.

Due to the considered mutual influence of transistors on each other, due to the introduction of the third windings of transformers 12 and 13 and their switching on, there is no delay with the drive from saturating any of the transistors. Moreover, the serial connection of transformer windings contributes to the alignment of the collector currents of the transistors. Indeed, since the currents of the windings 16 and 17 are equal in series, therefore, the currents of the windings 19 and 20 are also equal, in fact, the collector currents of transistors 10 and 11 are forcibly equalized by transformers 12 and 13.

The converters in figure 2 and 3 work almost the same as discussed. Similarly, in them, the voltage equalization at the capacitors 1 and 2 of the input filters occurs in the on state of the transistors 10 and 11, and at the capacitors 3 and 4 of the output

filters - on the interval off. As regards the process of aligning the switching on and off times of the transistors Yu and 11 using the additionally introduced third windings 19 and 20 in transformers 12 and 13, it proceeds completely identical to that considered, and the Q transient effect is achieved

exactly the same as in the converter of figure 1.

Thus, the invention makes it possible to distribute the voltage of the power supply between successively connected pulse controllers with greater accuracy. This eliminates the transistor overload voltage across all phases of operation and for any relative duration of their on state. As a result, the reliability of the converter

5 and also increases its efficiency by reducing the equalizing currents. A positive factor for the introduction of third windings into transformers is also the fact that their magnetizing force can be used to create unlocking currents of the transistor bases and thereby reduce the output power of the control unit.

Claims (1)

5 claims A dc voltage transducer containing pulse polarity regulators of different polarity connected in series to the input and output, each with different polarity, each of which consists of an input capacitive filter, to which the power transition of the transistor is connected, and an output inductive capacitive filter with a reverse diode at the input The control transitions of the transistors are connected to the secondary windings of the first and second transformers, respectively. 0 windings of which are connected to the outputs of the control unit, and the windings of the output filter chokes are magnetically coupled, in order to increase efficiency, reliability, The g transformers mentioned above are provided with third windings, each of which is connected between the power junction of the transistor and the input filter output of the other regulator. Editor V. Danko Order 1779/53 Fig.d Compiled by I.Nikitin Tehred A. Kravchuk Circulation 665 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5 Proofreader G. Reshetnik