SU1525605A1 - Measuring transducer of electric signals of random shape - Google Patents

Abstract

The invention relates to electrical measuring equipment and solves the problem of measuring the power and the square of the effective voltage value. The purpose of the invention is to improve the accuracy in the study of signals of asymmetrical shape and enhanced functionality. The converter contains an adder 1 and 5, three quadrants 2-4, a generator 6 of triangular voltage. Each quadrator contains a comparator 7, an inverter 8, switches 9 and 10, the averaging block 11. Input signals proportional to current and voltage, respectively, are fed to the inputs of quadrants 2 and 4 and to the inputs of adder 1, the output of which is connected to the input of the quadrant 3. The voltage proportional to the power is removed from the output of the adder. 5. 2 Il.

Description

The invention relates to a measurement technique and can be used in devices measuring the effective values of arbitrary electrical signals, as well as power, the invention solves the complex measurement of the square of the effective value, current and voltage of an arbitrary shape, for example, non-cross-section, also their active power.

The purpose of the invention is to expand the functionality due to the possibility of simultaneously measuring the power of an electrical signal and the rms values of current and voltage, increasing the accuracy in the study of signals of asymmetric shape.

FIG. 1 shows the block diagram of the proposed device j on. 2 - time diagrams of work.

The device comprises an adder 1, a left 2, a second 3 and a third 4 blocks for converting electrical signals into a square of the effective value (quadrs), an adder 5, a generator 6 of triangular voltage. Each quad includes a comparator 7, an inverter 8, keys 9 and 10, averaging unit 11. The first input of the device is connected to the first input of the first adder 1 and the input of the quad 2, the second input is connected to the input of the quad 4 and the second input of the adder 1, the output of which is connected to the input of: Quad 3, The outputs of Quad 2 and 4. Are device codes and are connected to the first and third inputs of the adder 5, to the second input of which the output of the quad is connected 3. From the output of the adder 5, output of the device, remove the signal proportional to oschnosti.

The device works as follows. The input normalized voltage Uy (t), proportional to the voltage across the object, goes to the first input of the device, and the second normalized voltage U; (t), proportional to the current at the facility, is fed to the second input of the device. Adder 1 sums the input voltages) and U; (t) and. Brings their sum, in turn, to the new normalized value. Quad work parallel and similar. Consider, for example, the operation of the channel for converting the square of the effective voltage value.

From the first input of the device, the voltage Uy (t) goes to the first input of the first comparator 7, to the signal input of the first key 9, to the input of the inverter 8, where it is inverted, and post it to the signal input of the second key 10. The alternating voltage generator 6 is variable voltage) with amplitude reception UTmax-Uu mac. (Fig. 2a). The alternating triangular voltage U – r (c) is fed to the second input of comparator 7. Comparator 7 compares the voltages at its inputs (Fig. 26).

The first 9 and second 10 keys are controlled by logically opposite signals, i.e. when a high level signal is present at the control input, the first key 9 is open and the second key 10 is closed. Thus, o6pa30Nf, the first key 9 forms from the input voltage Uy (t) a pulse sequence at time intervals when Uy (t) Uy (t), and the second key 10 forms a pulse sequence from the inverse voltage Uy (t) at time intervals when U (j (t) Ur (t). Both pulse sequences arrive at the corresponding inputs of the averaging block 11, where they are summed and C mean.

From (2) it is known that the voltage Uep, obtained by averaging the pulses of the first sequence of the positive half-wave T, is equal to m,

  . m (-t, + 2Tit „„, with TI

 U, (t) dt,

UCP ... i --- (t) dt + -

a, the voltage U;. obtained by averaging the pulses of the second sequence is equal to m,

 (t) dtg J

 t max

21 1

Uu (t) dt.

Total averaged voltage

Ucpt,

ty, 1

1 U4t) dt,

Poppy

51525605

Similarly for negative sex

tensions Tg

TUrMOIKC

Uu (t) is equal to

uenie u

z

 UJ (t) dt,

CPU pulses

received for the entire period

one

ti

t / iox

I

 U $ (t) dt.

Thus, the input voltage conversion is fully implemented in one half-period, which removes the fundamental restrictions on the symmetry of the half-waves in both spatial and temporal ratios, which increases the conversion accuracy for an arbitrary shape of the measured voltage.

At the output of the third quad, we have

t 1

 TUT:;.;

and,

U (t) dt

The power is determined using adder 5 according to the following relationship

tt

P - | - j U, (t) Ui (t) dt - i j Uu (t)

0o

+ U -, (t) -U2 / t) -U2. (T) dt,

 -i- uu (t) (t) Mt

, u5 (t) .dt - - | -J u (t) dt.

Where do we get

2 uattf

(.p, -U.

R:

t) H

Claims (1)

Invention Formula Measure an arbitrary-shaped converter of arbitrary-shaped signals containing three signal conversion units into a square of the effective value (quad), two adders, the inputs of the first of which are inputs of the device, and the output connected to the input of the second quad. The 15 output of which is connected to the second input of the second adder, characterized in that, in order to catch the accuracy and enhance the functionality, a triangular pulse generator is inserted into it, the input of the first quad is connected to. the first input of the device, the output is connected to the first output of the device and to the first input of the second adder, The second quadrant input is connected to the second input of the device, the output is connected to the second output of the device and the third input of the second adder, the output of which is the third output 30 of the device, the output of the triangular pulse generator is connected to the clock inputs of the quadrants, and each quad includes an inverter, a comparator, two keys and an averaging unit whose output is a quad output, the inputs are connected respectively to the outputs of the keys, the information input of the first of which is connected to the input the second and the second to the output of the inverter, whose input is connected to the input of the quad, the control inputs of the keys are connected to the output of a cog-charger, whose inputs are connected respectively to the input of the quad and so Quad input. 35 40 FIG. 2 tks