SU1101986A1 - Process for converting d.c.to d.c.voltage - Google Patents

Abstract

A method of converting a DC current to a DC voltage is proportional to the magnitude of this current, at which the switching frequency of the magnet-transistor converter is changed by biasing the core of its transformer by a specified DC current, characterized by the fact that, in order to increase reliability and increase the bandwidth of the transformer, by the indicated direct current, characterized by the fact that, in order to increase reliability and increase the bandwidth of the transformers by the specified DC current, characterized in that, in order to increase reliability and increase the bandwidth of the bands, the indicated direct current will be different in that in order to increase reliability and increase the bandwidth of the bands, by the specified DC current, in order to increase reliability and increase the bandwidth of the bandwidth, the specified current will change, in order to increase the reliability and increase the bandwidth of the bandwidth. determined by measurement. average current consumed by the magnet transistor converter. from 00 O5

Description

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The invention relates generally to methods for converting a direct current into a constant voltage proportional to the magnitude of this current, and dp can be used to automatically adjust and control the current in industrial electric drives and converters.

A known method for converting direct current, in which the voltage taken from the shunt modulates, amplifies and demodulates C1. 3 However, this method is relatively complex and does not provide a sufficiently reliable galvanic isolation.

There is also known a method in which direct current is transformed with the help of direct current transformers, and a magnetic motor is balanced (the direct current force magnet is ac magnetically driven by alternating current with a constant frequency C 2.

However, in general, the method is applicable dp conversion of large currents and its use for regulation and protection is limited.

The closest to the invention to the technical essence is the method of converting direct current, which consists in that the current of the transformer of the magnetic transistor oscillator is magnetised and the frequency of its switchings (self-oscillations) is transformed, and the output voltage of the rectangular form is transformed into a sawtooth wave. and by the change in the amplitude of the latter is judged, the value of the monitored current C 33.

The disadvantage of this method is that during the formation of a sawtooth voltage, capacitors must be discharged to zero during each switching cycle of the magneto-transistor converter, which imposes a limitation on the frequency and, therefore, on the bandwidth of the converter. In addition, the method has insufficient reliability due to intermediate conversions and a possible failure of the charge-discharge capacitor process during interference.

The aim of the invention is to increase the reliability of the method and increase the bandwidth by eliminating intermediate conversions.

1101986

The goal is achieved by the method of converting direct current to direct voltage proportional to the value of this current at which the switching frequency of the magnet-transistor converter is changed by biasing the core of its transformer by the specified direct current the specified voltage values of the current consumed by the magnet transistor converter.

Timing charts are shown in city 1; Fig. 2 shows an example of a device implementing a method.

The diagrams (Fig. 1) indicate the input control current 1, which also magnifies the transformer core of the converter, 2 the voltage proportional to the current consumed by the converter, the output voltage 3 (average value or the result of the conversion).

The device implementing the method contains a magneto-transistor converter 4, a mixing source 5, a filter 6. The monitored Current 1 is passed through a separate conductor 7, which passes through the window of the core 8 of the converter A. The converter is powered from source 9 through a common resistor 10 and is a multivibrator, for example, with resistor collector connections; the collectors of transistors 11 and 12 are connected to the source through the transformer windings.

The method is carried out in a follow-up manner.

The switching frequency of a magnetic transistor converter is changed by biasing the core of its transformer with a constant KOHTponHpyetOiiM current.

The output voltage is obtained by measuring the average value of the current consumed by the magnetic transistor converter.

Consider the operation of a magneto-transistor converter in the double magnetization mode of its transformer core: alternating magnetic flux as a result of alternate flow of collector currents through transistors 11 and 12 and the transformer windings and constant magnetic flux from flow, input controlled current 1 through a conductor When there is no current, 1 core 8 re-magnetized in each switching cycle and the converter operates at a frequency determined mainly by the parameters of the transformer. At time, time For example, the transistor 11 opens, and the current through it rises to the stent ty from a certain time constant and to a level determined by the voltage of source 9 and a parameter in the {circuit connected by a resistor 10 "In the region of the increase of the collector current to the base of the transistor 11 is applied plus, i.e. to facilitate opening, the voltage across the collector-base resistor due to the magnetically connected transformer windings. When the collector current reaches its maximum value, the transistor moves to the active area of operation. The self-induction EMF of the collector winding begins to change its sign (the termination by positive processing of the connection) and the transistor 11 closes. At time t, it is completely closed by a negative voltage at its base, and at the same time, the positive potential at the base of transistor 12 will reach a certain level at which it will open, etc. Thus, in the current limiting mode by the resistor 10, the transistors 11 and 12 operate in the active mode, and the converter is in the current switch mode. In this case, then the resistor 10 flows continuously through the walls, i.e. the lower level of pulsations of the collector currents does not reach zero. When the transformer transformer transformer core 4 is magnetized by direct current 1 (time and below, FIG. 1) the partial cycles of magnetization reversal of the core of the inpspig and the switching frequency of the converter increases. In this case, the collector currents also reach their maximum values, and the lower level of the pulsations increases. This happens because the current through one transistor does not manage to decrease to the previous level by the moment of switching on the other transistor, as a result, the lower edge of the collector currents is set to another high level (time tj-t) until the magnitude of current 1 changes, etc. Accordingly, the average current consumed by the converter increases. If, instead of resistor collector-base links, capacitive (Fig. 2, dashed) is taken, the nature of the pulsation fronts of the current consumed by the converter will change (Fig. 1, current 2, dashed line) due to the forced opening of transistors 11 and 12, and the average the value of current 2 will vary in a similar manner. It is only important that in all cases at least one of the pulsation fronts be linear for a proportional change in voltage 3 depending on current 1. Since the converter consumes current and in the absence of current 1, i.e. voltage 2 has a certain value; if necessary, it can be compensated for by the source, com 5. Output filtered voltage 3 (.1) more accurately conveys information about input current 1, the greater the initial switching frequency of the converter, and the bandwidth that the proposed method allows to increase by an order by eliminating intermediate conversions. At that, since the transformer core of the converter is not sensitive to the direction of the constant bias flow, the proposed method can control the alternating current at a sufficiently high frequency. In the case of control of large currents (above 10A), the magnetization of the transformer transformer core is produced frequently by the current, i.e. the power conductor is split and a smaller conductor is passed into the core oxide, taking into account its diameter, the width of the main conductor and the magnitude of the current. Thus, the conversion of direct current to direct voltage is relatively simple, with greater bandwidth and more reliably, which expands the scope of application of the method in both pulsed and continuous systems of control and control of current in promsmennyh electric drives

S11019866

direct current and transducers, for example, with inductive installations. The proposed method of collector-base connections, including is implemented on other types of pre-single-ended circuits.

Claims (1)

METHOD FOR CONVERTING DC TO DC VOLUME, proportional to the magnitude of this current, at which the switching frequency of the magnetic transistor is changed by magnetizing the core of its transformer with the indicated direct current, characterized in that, in order to increase reliability and increase the passband, the voltage is determined by measuring the average value of the current consumed by the transistor.