RU2001409C1 - Device for determining phase relation of two sine-wave signals - Google Patents

Abstract

Usage: field of measurement technology, the determination of the phase ratios of two sinusoidal signals. SUMMARY OF THE INVENTION The device comprises a divider 1. A differentiator 2, a registration unit 3 2 or

Description

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The invention relates to measuring equipment, in particular to devices for determining the phase relationship of two sinusoidal signals, in particular to devices for determining the sign of the phase difference of signals, and in particular to devices for determining the sign of the phase difference of voltage or current signals of the same frequency, and is intended for predominant use in precision devices that maintain high accuracy of sign determination at small or close 90 °, 180 ° absolute values of this phase difference in the infra-low-frequency range, when the amplitudes of the signals can vary among themselves and vary widely.

Various devices are known for determining the phase relationship of two sinusoidal signals in the measurement of shifts

FGEZ.

Such devices are characterized by considerable complexity due to the large number of auxiliary units used to generate additional pulses at certain points in time, compare time intervals, determine modulation coefficients, correlation and perform other functional transformations. In addition to difficulties in manufacturing, errors arise in determining the sign of the difference for small shifts and close 90 °, 180 ° of their absolute values, as well as for the small amplitude of at least one of the signals whose frequency lies in the infra-low frequency range.

Under these conditions, the error becomes significant due to the fact that at infralow frequencies the signal change rate decreases significantly and the response time of threshold devices becomes ambiguous, especially for small amplitudes (or amplitudes of at least one of the signals) and phase differences that are multiples of 90 °, while the durations of the generated additional pulses have a significant spread, which also increases the error in measuring the sign of the phase difference.

A device 4 is known, containing primary and secondary formers, two triggers and logical elements NAND.

The device is characterized by insufficient accuracy in measuring the phase difference at small signal amplitudes in the infrared frequency range at phase shifts of close and multiple 90 °

A device based on measuring phase shift using digital codes is known, comprising three pulse shapers connected to three inputs of the device, two of which are signal and the third is opera, a pulse counter, a generator, registers, and a comparison unit connected to the output of the device.

The disadvantage of this device is a significant increase in measurement error at small amplitudes of the studied

signals of the infra-low frequency region, and especially when the phase difference between them is close to zero or a multiple of 90 °.

This drawback is inherent in all threshold-type devices, the principle of operation

5 of which is based on a comparison of the test voltage with a threshold, and the error is due to the uncertainty of the response time of the corresponding units of the device when operating in the specified conditions.

0 The closest technical solution to the claimed for a large number of similar essential features is a device for determining the phase ratio of two sinusoidal signals 5 containing an integrating device, a differentiating device, a multiplier and a recording device - a zero organ or comparator. The input signals are integrated accordingly.

0 are differentiated, then multiplied and fed to a recording device, which has a signal output equal to zero at phase ratios between sinusoidal signals of 0 or 180 °.

5 The device is quite simple, however

has errors when reducing the amplitude of the studied signals. In addition, the device does not detect the sign of the phase difference between the signals.

0 The aim of the invention is to expand the functionality of the device while maintaining its simplicity.

The goal is achieved in that the device for determining the phase relationship of two sine-sine signals, comprising a differentiating device and a recording unit, the output of which is the output of the device, further comprises a division unit, the two inputs of the division unit being one for the divisible signal and the other for the signal -divider, connected to two inputs of the device, differentiating device and registration unit are connected in series with the division unit.

5 in FIG. 1 shows a functional diagram of a device; in FIG. 2 - time diagrams of the operation of the device.

The device comprises a division unit 1, a differentiating device 2, a registration unit 3.

Two inputs of division unit 1 are connected to two signal inputs of the device - marked by signals Ux (t). Uy (t) in FIG. 1. The output of the division unit 1 is connected to the input of the differentiating device 2. The output of which, in turn, is connected to the input of the registration unit 3.

The device operates as follows. Sinusoidal signals Ux (t) and Uy (t) are fed to two inputs of division block 1 and one of them, for example, Ux (t) is divisible, and the second Uy (t) is a divider.

The quotient of the division of the studied signals, equal to the voltage Ui, is a periodic function that varies according to a law close to the tangent or cotangent, and, depending on the sign of the phase difference of the initial signals, will be either a decreasing function on each half-period T of the signal the divider Uy (t), as in FIG. 2 for a positive phase difference, or an increasing function for a negative phase difference. The approximation of the dependences is due to the fact that at the beginning and end of each half-period the functions will have not infinite, but some finite value A.

The voltage signal Ui is supplied to a differentiating device 2, which differentiates the signal, and signals, voltage pulses Ua of a certain polarity determined by the form of the signal Ui, are received at the output of the differentiating device 2, i.e. a sequence of pulses of positive polarity is obtained if the divisible signal is ahead of the phase of the divider signal (Ui has the form of a cotangent), or a sequence of negative pulses is obtained if the equilibrium signal lags behind the divider signal in phase (Ui has the form of a tangent).

Thus, a sequence of pulses, the polarity of which is determined by the sign of the phase difference of the studied signal, is input to the input of the registration unit 3.

DEVICE FOR DETERMINING THE PHASE RELATIONSHIP OF TWO SINUSOIDAL SIGNALS. A differentiating device and a regeneration unit, the output of which is the output of the device, characterized in that it further comprises a unit

fishing The registration unit 3 may be either a comparator, or an integrating voltmeter, or some other device having an output signal for

pairing with other devices or other necessary indication,

, Information about the sign of the phase difference is needed either in the phase measuring devices, and then the obtained sequences

converted into control pulses for a common measuring circuit, or this information is necessary for self-registration, in this case, the polarity of the pulse sequence can be

it is determined, for example, using a pointer instrument with a zero in the middle of the scale or with digital recording these sequences can be used as logical control pulses.

The claimed device is made on standard elements: the side of division 1 is made four-square (7a). since it receives signals of different polarity

and time varying. The differentiating device 2 is given in (76), and the registration unit in the form of a comparator is given in 7c.

(56) 1. USSR author's certificate No. 1138760, class G 01 R 25/00, 1984.

2. USSR Certificate of Authorship

No. 1503025.cl. G 01 R 25/00, 1989.

3. USSR Certificate of Authorship

No. 1503026, class C 01 R 25/00, 1989.

4. USSR Certificate of Authorship

Ms 1195275, cl. G 01 R 25/00, 1986. 5 Copyright certificate of the USSR

No. 1167524. cl. G 01 R 25/00, 1985. 6. USSR Copyright Certificate

N 256865, cl. G 01 R 25 / 00.1973. 7. A.G. Alekseenko, E.A. Colombet, G.I. Starodub. Application of precision analog A. S. M: Sov. Radio 1980: a / c 96-97.fi/c. 96-97. with. 82-84, v / s. 168.

division, and two inputs of the division unit, one for the divisible signal, the other for the divider signal, connected to two inputs of the device, a differentiating device and a registration unit are connected in series with the division unit.

FIG. 2