SU131828A1 - Electronic amplitude voltmeter - Google Patents

Description

The proposed voltmeter for measuring the amplitude values of alternating voltage voltage of an infra-low frequency is a known type of device based on measuring the charge of a capacitor charged from a source of measured voltage to the amplitude value of the latter.

The novelty of the proposed amplitude voltmeter consists in using a system of three capacitors, each of which is charged with a measured voltage to the amplitude value of the latter and, after measuring its charge, is discharged to zero.

In this case, simultaneously with the charge of one of the capacitors, the charge of the second and the discharge to the third zero are measured.

Such a device makes it possible to continuously measure the amplitude values of the infra-low voltage.

The necessary switchings can be carried out using a ring scaling circuit and a system of electronic switches of the type of flip-flops, which are controlled directly by the measured voltage.

FIG. 1 shows the block diagram of the proposed voltmeter; in fig. 2 - graphs of voltage changes in time: measured f / ,, at the output of the former of the module Ug, on each of the capacitors and. , and sg, sz and the output composition of the described voltmeter (Fig. 1) include the following main components: driver / input voltage module, driver 2 pulses, ring scaling circuit 3, three forming asymmetrical trigger 4, 5 to 6, three input switches 7, 8, and 9, three output switches 10, 11, and 12, three switches of capacitors 13, 14, and 15, three storage cascades 16, 17, and 18 on capacitors Ci, Cj, Cz (not shown) and output sum1 steering cascade 19.

No. 131828-2 Module 1 shaper is used to produce at its output a voltage equal in magnitude to the measured, but only one (negative) polarity. {Fig. 2, U g), which makes it possible to measure at each half period. Then, the module of the measured voltage is applied to the inputs of the keys 7, 5 and 5. The shaper of 2 pulses serves to receive negative polarity pulses every half period. These pulses are fed to an annular scaling circuit 3, the voltage from the three outputs of which is supplied to the triggers 4, 5 v (6.

The graphs of the magnitudes of these voltages are identical in shape, but shifted in time by a half period. This provides a shift by half a period generated by control voltage triggers for keys 7–15. This shift allows you to simultaneously open three keys out of nine, namely:

a) during the first half period, keys 7, 14 and 12 are opened;

b) during the second half period - keys 8, 15 and 10;

c) during the third half period - keys 9, 13 and //.

As a result of this, on the capacitors of the storage cascades 16, 17 and 18, the voltage changes occur according to the IC, CI, and C3 charts (Fig. 2). As can be seen from these graphs, the work of the scheme proceeds in three stages. In the first stage (in the first half period), capacitor Ci is charged to an amplitude value, capacitor GS is discharged to zero (U s), and previously obtained voltage is transferred from capacitor Cz to a circuit output (in the form of a constant voltage the amplitude of the input voltage in the previous step.

At the second stage, capacitor C will transmit the output voltage amplitude value to the output. Capacitor C will be charged to an amplitude value, and capacitor Cz will be discharged. In the third stage, capacitor Ci will be discharged, the output voltage will be reproduced from capacitor C, and capacitor Cz will again be charged before and out of the device output will result in the resulting output voltage b,.,.

Subject invention

Claims (2)

1.Electron amplitude voltmeter, based on the use of a capacitor charge through a rectifier with a measured voltage up to the amplitude value of the latter, characterized in that, to measure alternating voltages of an infra-low frequency, a system of three capacitors is used, alternately with a time shift measured to the amplitude values of the measured voltage, and then after measuring the discharges in the same order so that the charge of one of them occurs when measuring the charge of the second and the discharge of the third end ensatora. 2. A voltmeter according to claim 1, characterized in that for switching capacitors, a system of electronic switches and a ring scaling circuit are used, which are controlled directly by the measured voltage.