SU659960A1 - Method of comparing two harmonic signals of equal frequency by amplitude - Google Patents

Description

any phase shifts between the compared signals.

This goal is achieved by the fact that in the method of comparing harmonic signals based on the formation of additional signals and the comparison of additional signals, the first additional signal is formed proportional to the time interval, the beginning of which coincides with the transition point through the zero level of one of the compared signals the point of any transition through the zero level of another compared signal, form the second and third additional signals by a full-wave Straightening each of the compared signals, respectively, form the fourth and fifth additional signals separated from the second and third additional signals during the time the first additional signal is valid, form the sixth additional signal proportional to the difference of the fourth and fifth additional signals, and information on the amplitude ratio receive the sign of the sixth additional signal.

A device for implementing this method contains two devices, their devices, the outputs of each of which are connected in parallel, and each of them separately with the inputs of the first and second pulse formers, the outputs of the pulse formers are connected to the first and second inputs of the trigger, the output of which is connected to the trigger, their inputs to the integrators, the outputs of which are connected in parallel, and each of them separately with the first and second inputs of the comparison circuit, two full-wave rectifiers, each of which is connected between the output of One of the coordinators, their devices and their respective integrator.

The formation of the second and third additional signals by full-wave straightening of each of the compared signals, the fourth and fifth additional signals separated from the second and third additional signals, allows to form a sixth additional signal proportional to the difference of the fourth and fifth additional signals, the sign of which depends on the ratio of the amplitudes of the compared signals and does not depend on the phase shift between the compared signals.

FIG. Figure 1 shows the time diagrams, as shown, the proposed method, where / 1 and t / 2 are the compared signals, f is the phase shift of the voltage Ui relative to the voltage in FIG. 2 shows a device for implementing the proposed method.

FIG. 1a corresponds to the phase shift between the compared signals less

l and fig. 16 corresponds to the phase shift between the compared signals more l. From the compared signals L / i and 1/2 (Fig. 1, line a) form additional signals, the first of which is formed proportional to the duration of the time interval, the beginning of which coincides with the transition point through the zero voltage level Ui and the end with the nearest transition point through the zero voltage level 1/2 (Fig. 1, line /), the second and third additional signals (Fig. 1, lines b and c) are formed by full-wave rectification of the compared signals. The fourth and fifth additional signals are formed by separating them from the second and third additional signals during the time of the first additional signal (Fig. 1,

20 line g, h, the sixth additional signal is formed in proportion to the difference of the fourth and fifth additional signals (Fig. 1, line k).

A device for implementing the proposed method (Fig. 2) contains matched devices 1, 2, shapers of time intervals 3, 4, trigger 5, full-wave rectifiers 6, 7, integrators 8, 9, comparison circuit 10.

0 The device works as follows.

The compared signals t / i and U (Fig. 1, line a) are fed to pulse shapers 3, 4 and full-wave rectifiers 6, 7. Pulse driver 3 generates narrow pulses at the time of transition through the zero voltage U (Fig. 1 , line d), and pulse shaper 4 generates narrow pulses at the moment of transition through the zero voltage level Uz (Fig. 1, line f). Narrow pulses from pulse formers 3, 4 are fed to the inputs of trigger 5, which forms a square pulse (Fig. 1,

5 line /), the beginning of which coincides with the moment of the appearance of the first of the pulses, and the end coincides with the moment of the appearance of the second pulse. Corrected by full-wave rectifiers 6 and 7, the equivalent signals U, Uz (Fig. 1, lines 6, c) are sent to the information inputs of integrators 8, 9, the control inputs of which receive a pulse from the output of trigger 5, which enables the integrator 8, 9 for the duration of the square pulse. From the output of the integrators 8, 9, the fourth and fifth additional signals (Fig. 1, lines g, h) go to the comparison circuit 10. The comparison circuit 10 generates a signal proportional to the difference of the fourth and fifth additional signals to its inputs (Fig . 1, line k). The sign of the signal (Fig. 1, line / g) at the end of the first additional signal (Fig. 1, line /) gives

unambiguous information on the ratio of the amplitudes of the compared signals.

Using the proposed method of comparing two harmonic signals of the same frequency in amplitude, and a device implementing the proposed method, makes it possible to eliminate the ambiguity of information about the ratio of the amplitudes of the compared signals during any phase shifts.

Claims (2)

1. USSR author's certificate number 425118, cl. G 01R 19/10, 1972. 2. USSR author's certificate number 425117, cl. G 01R 19/10, 1972. g fyy.g