SU1239623A1 - Device for measuring harmonic coefficient - Google Patents

Abstract

The invention relates to instrumentation technology and can be used in monitoring signal sources and communication lines. The purpose of the invention is to expand the functionality provided. possibility of determining the coefficients for individual harmonics. The device contains a selective filter 1, an adder 3 and a switch 4. To achieve this goal, N-1 selective filters, a detector, a ratio calculation unit 5, a display unit 6 and a control unit 7 are added to it. The choice of the position of the switch corresponding to the calculation of the total harmonic coefficient or the calculation of its value for each of the components is made from control unit 7. The coefficients calculated by the block 5 are displayed by the display unit, 1 slug. o (L 00 with Od tc 00

Description

 I

The invention relates to a test and measuring technique and can be used to control sources of signals and lines of communication.

The aim of the invention is to expand the functionality, which consists in the possibility of determining the coefficients of the pho to individual harmonics, which allows us to expand the field of application of the device:

The drawing shows a block diagram of a device for measuring harmonic coefficients.

The device contains a voter. nk filters 1-1 - -p, p detector 2-1 - 2-f rms value adder 3, switch 4, ratio calculation block 5, display unit 6, control block 7, with the inputs of all selective filters 1-1 Gl merged and connected to the input device, as well. the outputs of the selective filters 1-2 - 1-I through Detectors 2-2 - 2p are connected to the corresponding inputs of switch 4 and adder 3, the output of which is connected to one of the inputs of switch 4, the output of which is connected to one of the inputs of the ratio calculation unit 5, the second input of which is connected through the detector 2-1 to the output of the selective filter 1-1, and the display 6 is connected to the output of the ratio calculation unit 5.

The device works as follows.

In the initial state, the first selective filter 1-1 is tuned to the frequency-fo of the measured signal, and each i.- and l-i- filter to the frequency of the corresponding harmonic of the signal i f (). .

Selective filters 1-1 through -f select the harmonic components of the input signal with the harmonic number, from 1 to f | . At the outputs of the detectors 2-1 - 2-c, the root-mean-square values of the voltages of the corresponding harmonics are formed.

The rms values of the voltages of all harmonics, beginning with the second, are sent to the first a-1 inputs of the switch 4, the last input of which is summed cp €; the square-root value of all harmonics except the first, from the output of the adder 3.

The ratio calculation unit 5 performs a calculation operation eg 39623

zhen arriving at his entrance with

switch output, the voltage arriving at its other input from the output of the first detector 2-1. Thus, the root-mean-square value of the voltage of the first harmonic always acts as the divider, and the dividend depends on the switch position) Q or the root-mean-square value of the voltage of any of I 2, ..., n harmonics, or switch in the lower position of the rms value of the average

J5 of all harmonics except the first. In this case, in the latter case, the signal at the output of the ratio calculation unit 5. corresponds to the value of the harmonic coefficient, and in other positions

20 of switch 4 — the coefficient of nonlinear distortion at the selected harmonic; the values of the coefficients calculated by block 5 are displayed by block 6 of the display. .

25- The selection of the position of the switch corresponding to the total harmonic coefficient or the calculation of its value for each of the jt -x components is performed with the control unit 7.

KoiviMyTaTop 4 it is advisable to perform on the basis of mechanical switches or on the basis of integrated I analog commutators designed to sequentially switch several sources to a single load, such as on the basis of integral switches MOS, CMOS, or other structures with control of typical integrated logic circuits35

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A device for measuring the harmonic coefficient, which contains a selective filter, an adder and a commutator, differs from the fact that, with q (2) to expand its functionality, Jfl-l selective filters, N detectors, are entered. of which are connected to the output of the corresponding selective filter, the serially connected ration calculation unit and the control unit and the box, the control unit whose output is connected to the control input of the switch, each input is connected to the output of the corresponding detectors ora, and one of

31239623-4

the inputs are connected to the output of the adder, the supercooled relation unit, the second inputs of which are connected to the corresponding input of which is connected to the output, specifically to the outputs of the detectors, starting. mutator, - and the inputs of all the electors from the second, with the output of the first. The filters are combined and connected to a detector connected to the first input of the device.

Claims (1)

Claim Device for measuring the harmonic coefficient, containing a selective filter, adder and switch-: torus, characterized in that, for the purpose of expanding the functionality, selective filters are introduced into it, Ν detectors5® tori .. each input is connected- ^; The output of the corresponding selective filter is a series-connected ratio calculation unit and an indication unit, a control unit, the output of which is connected to the control input of the switch, each input of which is connected to the output of the corresponding detector, and one of the inputs is connected to the output of the adder, the inputs of which are connected respectively to the outputs of the detectors, starting from the second, while the output of the first, the detector is connected to the first input of the ratio calculation unit, the second input of which is connected to the output of the switch pa - and the inputs of all electoral filters are combined and connected to the input device.