SU766007A1 - Voltage measuring device - Google Patents

Description

(54) DEVICE FOR MEASURING VOLTAGE

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The invention relates to measuring and computing techniques and can be used in voltage converters in a digital code, digital measuring instruments.

A device for measuring voltage, containing switches, a DC amplifier, two comparators, a linear-variable-voltage generator, a capacitor, a controlled current source, an I circuit, a pulse generator, and a pulse counter 1, is known.

The disadvantage of the device is that it performs zero correction in several cycles, which reduces speed, has an error of zero setting due to the presence of two comparators and a storage capacitor, zero correction is performed when the measured voltage source is turned off - 20, which is not permissible, for example, in matched chains and chains containing reactive elements.

It is also known a device for measuring voltage, containing after-voltage the first element I, the first pulse counter, the code-to-voltage converter, and the scale converter, to the second input of which the first terminal is connected.

control course, second device. and the third output of which is connected respectively to the first inputs of the first and second element I, the output of the latter is connected to the input of the second counter, the controlled divider 2.

The disadvantage of such a device is the presence of a residual error in the installation of the pulleys, which is fundamentally unresolvable during the calibration process, since the xenpression voltage does not fully balance. displacement voltage. In the process of calibrating the device, the input circuits are switched, which is often unacceptable. During the measurement, a large number of operations are performed, which reduces the speed.

The purpose of the invention is to increase the accuracy and speed of the device.

Claims (2)

This goal is achieved in that a voltage measuring device containing the first AND element in series, the first pulse counter and the code-to-voltage converter and the large-scale converter, the second output of the control unit is connected to the second input, the second and third outputs of which are connected respectively to the first Tachodes of the first and second elements And the output of the last is connected to the input of the second counter, the control divider, the comparison resistor and the generator threshold unit, the input cat Through the controlled divider, it is connected to the output of the scaler, the input terminal of the device and the first output of the comparison resistor, the second output of which is connected to the common bus, the first output of the generating threshold block and the second element of the second and second output to the input of the control unit, the first output of which is connected to the control input of the controlled divider. FIG. 1 shows a block diagram of the device; in fig. 2 and 3 are diagrams explaining the operation of the device. The device for measuring the voltage contains a comparison resistor 1, a controlled divider 2, included in the common adjustable electrical feedback circuit of the generator threshold unit 3 (for example, a harmonic oscillator), with a predetermined trigger threshold y, which ensures its self-excitation , element 4I counter 5, converter 6 code to voltage, scale converter 7, element 8 I, counter 9, control unit 10, one output of the comparison resistor 1 connected to the common bus and the other to the input terminal my output through a controlled divider with a generator threshold unit 3, in the course of forming the command pulses which are connected to the input of the control unit 10, and the information output of the sequentially connected element 4I, the counter 5 pulses and the converter 6 code to voltage with the input of the scaler 7 and the cage element 8 I - with the input of the counter 9, the first output of the control unit 10 is connected to the second inputs of the scaler 7 and the controlled divider 2, the second to the second input of the element 4 I, and the third to the second the input element I. Before the measurement is started, the transmission coefficients of the controlled divider 2 and the scale converter 7 are set to position i, the element 4 is opened from the control unit 10, and the positive pulses From the output of the generator threshold unit 3 are fed into the pulse counter 5 (FIG. 2) and convert the code converter to voltage 6 to the compensation voltage UK. BEFORE, until the voltage M becomes equal to the sum of the measured voltage U (and Un Element 8 And is closed and prevents the passage of pulses to the second counter 9. At the time of the end of the balance, oscillation failure occurs at the information output of the generator threshold unit 3 (FIG. 2B) and at the output of the transducer 6 of the code, a constant compensation voltage is set in the voltage (Fig. 2a and b): At the same time, the pulse of the command of oscillation failure from the pulse shaping output of the generating threshold unit 3 (2g) is fed to the input of the control unit 10 Upon a command from block 10, element 8 I opens, the transfer coefficients of the scale converter 7 and divider 2 are set to be the same and, depending on the required accuracy and measurement speed, equal to .f., Where i is the so on. W. 1 - J f J - r I .... Suppose, for example, that the transmission coefficients are set to - (i 0). Then the threshold - response of the generator threshold unit 3 becomes equal to -, and the compensation voltage Oc at the output of the scale converter 7 becomes equal. The equality is violated and at the information output of the generating threshold unit 3 pulses again appear, which are sent to both counters (Fig. 26). At the moment of the end of equilibration: - and, (Fig. 2a) and in the second counter 9 the code proportional to the difference compensation the output of the converter code to voltage 6, after, second and first balances:, -UK, 2U - "and" - (and (Fig. 2a). When measuring AC voltage, only one or several half periods variable voltage (Fig. 3). Claims: A device for measuring voltage, comprising a first And series element connected in series, a first pulse counter, a converter into voltage and a scale converter, to the second of which the first output of the control unit is connected, the second and third the outputs of which are connected respectively to the first inputs of the first and second element H, the output of the latter is connected to the input of the second counter, controlled by a divider, characterized in that, in order to increase accuracy and speed ystvi, it introduced a resistor and comparing the threshold generator unit having an input, through a controllable divider coupled to the output of the transducer scale, input | terminal device and the first terminal of the comparison resistor, a second end connected to the common bus, the first output of the threshold generator. The unit is connected to the second inputs of the first and second elements, and the second output to the input of the control unit, the first output of which is connected to the control input of the controlled divider. pr Sources of information that are all taken into account in the examination of 1 .... USSR Copyright Certificate 523527, cl. H 03 K 13/17, 1977, 2. Author's testimonySSSR 534863, cl. H 03 K 13/02, 1977. i I.-f ; 764JJO: ,, .jfei;.-.- i . .