SU1737359A1 - Phase meter - Google Patents

Abstract

This invention relates to a measurement technique. The purpose of the invention is to increase the speed when eliminating galvanic communication between signal sources. The device contains standardizing amplifiers 1.1 and 1.2, parametric zone generators 2.1 and 2.2, limiting amplifiers 3.1 and 3.2, generator 4, element EXCLUSIVE OR 5, key 6, generator 7 quantizing pulses and an indicator counter 8. 1 h. item f-ly, 1 ill.

Description

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The invention relates to a measurement technique and can be used to measure the mutual phase shift of harmonic signals while providing galvanic isolation of their sources.

The purpose of the invention is to increase the speed while eliminating galvanic coupling between signal sources.

The drawing shows a functional diagram of the device.

The phase meter contains normalizing amplifiers 1.1 and 1.2, parametric zone (field) generators 2.1 and 2.2, limiter amplifiers 3.1 and 3.2, a pump generator 4, an EXCLUSIVE OR 5 element, an electronic switch 6, a generator of 7 quantizing pulses and an indicator counter 8. The first and the second input terminals of the phase meter through the respective normalizing amplifiers

1.1 and 1.2 are connected to the signal inputs of the generators 2.1 and 2.2, the combined pump inputs of which are connected to the generator 4 of the pump, and the outputs through limiting amplifiers 3.1 and 3.2 to the inputs of the EXCLUSIVE OR element 5, the output of the latter to the control input of the electronic switch 6, through which the generator 7 of quantizing pulses is connected to the counter-indicator 8.

Each of the two-dimensional generators 2.1 and

2.2 performed on two ring magnetic cores 9 and 10, on which there are: pumping windings 11 connected in series and according to and connected to the pump input of a piezo-oscillator; the windings 12 are resonant, connected in series and oppositely and connected to the series circuit from the capacitor 13 and the variable resistor 14 and to the output of the band generator; control windings 15 connected in series and in accordance with and connected to signal inputs.

Phase meter works as follows.

The signals, the phase shift between which it is necessary to measure, arrive at the inputs of the normalizing amplifiers 1.1 and 1.2, where they are normalized (amplified or attenuated) to a level sufficient for controlling the effect on the gap generators. From the output of the normalizing dividers 1.1 and 1.2, the compared signals arrive at the signal inputs of the square generators 2.1 and 2.2. The low-frequency signal from the pump generator 4 is fed to the combined pump inputs of the 2.1 and 2.2 gap generators and then to the pump windings 11, which causes modulation of the reactive parameter (inductance). As a result, parametric oscillations in the higher instability zones occur in the resonant windings 12 and the circuit from the capacitor 13 and the variable resistor 14, provided that the signal inputs of the gap generators and then to the control windings 15 of the normalized compared signals. In the absence of signals at the inputs

The phase meters of the gap generators are in the mode of breaking oscillations in the resonant windings 12, which is ensured by the appropriate initial setting of variable resistors 14 in both piezo oscillators. When compared signals arrive at the control windings 15, oscillations with a frequency F occur in the resonant windings 12

F nfHaK, (1)

where n is a positive number, depending on the amplitude of the pump generator;

fna is the frequency of the pump generator, and the initial phases corresponding to the initial phases of the compared oscillations

(i.e., the phase of the oscillations being compared is subject to parametric oscillations). From the outputs of the 2.1 and 2.2 gap generators, parametric oscillations with phases equal to the phases of the signals, arrive

to the inputs of limiting amplifiers 3.1 and 3.2, respectively, where they are converted into sequences of pulses of a fixed frequency F, the initial phases of which correspond to the phases of the input signals. WITH

the outputs of limiting amplifiers 3.1 and 3.2, these pulse sequences are fed to the inputs of the EXCLUSIVE OR 5 element, at the output of which pulses are formed with a duration proportional to the phase difference of the compared input oscillations. These pulses are controlled by an electronic key 6 (opening it) through which the signal from the generator of 7 quantizing pulses with a frequency of 360 F enters the

the input of the counter indicator 8. Since the phase shift p is by definition equal to

f-sp. and

where t is the time interval defined by the phase shift p,

T is the oscillation period,

then when quantizing the time interval r with the frequency 360F, we get the result

p g-360R C p,

where T - p

Thus, the obtained quantization result (p is numerically equal to the phase

shift p. This result is recorded by an indicator counter 8.

The proposed phase meter increases the speed in comparison with the prototype, since obtaining the numerical value of the phase shift is reduced to a simple count of the number of pulses. The use of gap generators provides the appropriate ratio of the frequencies of quantizing pulses and the frequencies of the compared oscillations, and the measurements are performed at a high frequency.

Claims (2)

Claim 1. Phase meter comprising a generator, two limiting amplifiers, a key, one input of which is connected to the output of a quantizing pulse generator, and the output to the counter-indicator input, characterized in that, in order to improve its performance, AN ORDER, two normalizing amplifiers, the outputs of which are connected respectively to the first and second inputs of the first and second parametric band generators, the third inputs of which are connected to the output of the generator, and the outputs are connected respectively to the input E limiting amplifiers whose outputs are coupled to inputs of the EXCLUSIVE OR, the output of which is connected to the second input key. 2. Phase meter according to claim 1, characterized in that the parametric zone generator contains two magnetic cores with pump windings, resonant windings and control windings, the outputs of which are connected to the first and second inputs of the parametric zone generator, and the control windings are connected in series and according to , while the windings of the pump are connected in series and according to, and their conclusions are connected respectively to the third input and the common bus of the parametric zone generator, the resonant windings are connected in series They are oppositely connected, and their terminals are connected to the outputs of the series circuit from the capacitor and the variable resistor, respectively, while the capacitor terminal is connected to the output of the parametric zone generator, and the output of the variable resistor is connected to the common bus.