RU1798727C - Method for object phase shift determining - Google Patents

Abstract

Usage: digital phase meters for measuring or monitoring the phase shift introduced by dynamic objects, including high-frequency ones. The inventive form of the time interval of the signal at the output of the measured object at the moment of transition of the zero level and quantized, the difference of the invention is: measure the voltage and sign of the quantized signal in the moments before and after changing the sign of this signal, and also measure the sequence of changes of the input signal at the moment corresponding to the moment of the beginning of the time interval, the number of quantizing pulses is selected, the oscillation period of the input signal is a multiple of the quantization interval. The phase shift of an object is determined by the formula. 1 ill.

Description

The invention relates to measuring technique and can be used to measure or control the phase shift introduced by dynamic objects, including high-frequency ones.

The aim of the invention is to increase the accuracy of determining the phase shift of an object.

The drawing shows a block diagram of a variant of the device that implements the proposed method, which indicates:

1 - object

2 - generator of sinusoidal and clock signals (GTSS),

3 - computing unit (WB),

4 - quantizer.

The device operates as follows.

The input and output of the object are connected to the device via terminals a and b, respectively.

Generator 2 generates an input blue. a co-signal with a predetermined period T of oscillations (output 1), a signal about the passage of a sinusoidal input signal through a zero level (output 2), which starts the quantizing pulse count of the output signal in the computing unit 3, a quantization signal of the output signal (output 3). The oscillation period of the input signal is set as a multiple of the quantization interval of the output signal, moreover. that the zero values of the input signal coincide in time with the moments of quantization. The output signal, passed through quantizer 4, is fed to the first input of computing unit 3, in which information about the last two samples is constantly stored, with each path replaced by the previous one with the current one. In the computing unit, the signs of the last two samples are compared. At the time of quantization, when the sign

ate

WITH

3

00

and

vi

of the current sample for the first time does not coincide with the sign of the previous sample, the last pair of samples is fixed, the number of quantizing pulses K 1 + 1 from the beginning of the measurement of the time interval and the modules of the fixed samples (Uebixi), (new2) are determined. Using this data, the duration of the time interval and, accordingly, the main value of the phase shift are determined by the formula (1), by the calculation method. In addition, in the computing unit 3, the sequence of the Signs of the input and output signals and for different sequences is determined The main value of the phase a shear p is added according to formula (2) 180 and a certain phase shift value is applied to the output terminal of the device.

SUMMARY OF THE INVENTION A method for determining the phase shift of an object, which comprises inputting a measured signal to an object to be measured and generating a time interval that is proportional to the phase shift, wherein the time interval starts at the time of the transition with the zero level input signal, the time interval is quantized, and I determine the phase shift of the object from the calculated number of quantizing pulses, characterized in that, in order to increase the accuracy,

0

0

5

0

5

the time of the end of the time interval is determined by additionally measuring the values of the voltage and sign of the signal corresponding to the moments before and after changing the sign of this signal, as well as measuring the sequence of the sign of the input signal at the moment corresponding to the moment of the beginning of the time interval, and the number of quantizing pulses I is taken equal to K-1 (where K is the number of measured quantizing pulses), the oscillation period of the input signal is set as a multiple of the quantization interval, and the phase shift p of the object is defined by the formula

/ l - 1YAL G D (i 1- «s, Р - (I + ГГГ --- ГТТм-- |) 1 V | Tsvykh2 | + | TsvykhG

+ risigri UxMlsign LUxVrislgn UBxAnslgn U8X

where is the D quantization interval,

T is the period of fluctuations of the input signal, output1, output2 is the value of the voltage of the quantized signal, respectively, before and after changing the sign of this signal, nslgnUex.DslgnUabix is the sequence of changing the sign of the input and output signals, respectively, and rislgn U 1 when changing the sign from - to

Hi and

FlsfgnU 0 when changing Sign + to