SU1228033A1 - Apparatus for forming numerical equivalent of measured parameter - Google Patents

Abstract

The invention relates to a measurement technique and can be used in digital devices for measuring periods. The purpose of the invention is to increase the measurement accuracy. The device contains a cumulative counter 1, counters 2 and 3, element 4 OR, elements 5 and 6 AND, trigger 7, logic block 8, block 9 of memory and block 10 of control. Introduction to the device of counters 2, 3, logic unit, control unit, WL element, memory unit and the formation of new connections between device elements will ensure that there is no change in the generated numerical equivalent of the measured parameter when the measured parameter fluctuates depending on its average value to 1 / 6-1 / 3 of the magnitude, corresponding to the weight of the youngest category. 2 tab., 4 Il. i (L

Description

The invention relates to a measurement technique and can be used in digital devices for measuring periods.

The purpose of the invention is to improve the measurement accuracy.

Figure 1 shows the functional diagram of the device for generating a numerical equivalent of the parameter being measured; ff, 2 is the axis of the values of the parameter being measured and its numerical equivalent; in FIG. 3, a change in the limiting amplitude of oscillations of the measured parameter, before which it is reached, there are no fluctuations in the number equivalent i depending on the average value of the measured parameter; 4 shows timing diagrams of the output signals of the control unit.

The device for generating a numerical equivalent of the parameter being measured contains a cumulative counter 1, the first 2 and the second 3 additional counters, the OR 4 element, the first 5 and the second 6 elements AND, the trigger 7, the logical block 8, the memory block 9 and the control block 10. The counting input of the cumulative counter 1 is connected to the output of the first additional counter 2, the counting input of which is connected to the output of the element OR 4, the first and second inputs of the element OR 4 are connected to the outputs of the elements 5 and 6. The first and second installation inputs of the trigger 7 are connected to the outputs of the logic unit 8, the first and second inputs of which are connected to the outputs of the bits of the second additional counter 3. The output of the trigger 7 is connected to the first input of the second element AND 6. The counting input of the second additional counter 3 is connected to the output p The first element And 5 signal inputs of memory block 9 are connected to the bits of accumulative counter 1. The first output of control block 10 is connected to the set inputs of accumulative and first additional counters 1 and 2, second, third, fourth, fifth and sixth outputs. the control unit is connected. respectively to the installation input of the second additional counter 3, the third input of the logic unit 8, the nepBbiM input of the first element And 5, the second input of the second element And 6 and the installation input of

0

five

ka 9 memory. The first input of the control unit 10 is the first input 11 of the device, and the second input of the first element AND 6 is the second input 12 of the device.

A device for generating a numerical equivalent of the parameter being measured works as follows.

Input 12 receives impulses that are counted during the formation of a numerical equivalent, and input 11 receives impulses, defined as the duration of the time intervals for which the numerical equivalent is produced, i.e., the periods of impulses arriving at input 12 are made the quantization of time intervals, the information about the duration of which is fed to the input 11. For the pulse counting time, the first element AND 5 is open by the signal from the control unit 10 (Fig. 4a), and the second element And 6 by the signal from the control unit 10 is closed (.4b) The pulses from the input 12 are fed to the counting inputs of the additional counters 2 and 3, and from the output of the first additional counter 2 to the counting input of the cumulative counter 0. 11. The conversion factor of the additional counters 2 and 3 is assumed to be three. After the quantized time interval, for which vpbrfi produces the formation of a numerical equivalent of the measured parameter in accumulative counter 1, the signal from control unit 10 sets the pulse to the input element And 6 (fig.4b). If trigger 7 is in the single state, then an additional impulse is sent from the output of element 6 to the counting input of the first additional counter 2. If trigger 7 is in the zero state, no additional impulse is fed to the input of counter 2.

When an additional pulse is applied to the input of the counter 2, two situations can occur.

If previously the number 2 was fixed in counter 2, the arrival of an additional pulse to the input of counter 2 leads to the transition of this counter to the zero state and the supply of an additional pulse from its output to the input of accumulative counter 1. Therefore, to the number previously formed in the counter 1 is added one

0

five

0

five

ca, i.e. Correction of the generated numerical equivalent of the measured parameter occurs. In other states of counter 2, this will not happen. Then, from control unit 10, a pulse is applied to the input of logic unit 8 (Figure 4b). In this case, if in the additional counter 3 the O number is fixed, a signal is output from the output of the logic unit 8 to the input of the trigger 7, which sets it to the one state. If in the additional counter 3 the number 1 is fixed, then from the output of logic block 8 a signal is sent to set the trigger 7 to the zero state. If the additional counter 3 is fixed with the number 2, then the signal from the output of logic block 8 to the switching of trigger 7 will not arrive and the trigger 7 will retain the previous state. By signals from the control unit 10, the number recorded in accumulative counter 1 is entered into memory block 9 (Fig. 4d), and then accumulative counter 1 and additional counters 2 and 3 are reset to the initial state by signals from the outputs of control unit 10 (Fig .4d). Further, the cycles of forming the numerical equivalent of the parameter being measured are repeated. Therefore, if in the current measurement cycle in the additional counter 2 the number two is fixed, and in the additional counter 3 in the previous measurement cycle the number is fixed zero or in the previous measurement cycle in the additional counter 3 the number two is fixed, and before that the number zero was fixed in it, One more pulse is added to the number of pulses counted by a cumulative counter 1. Thus, the generated numerical equivalent depends not only on the value of the measurement

parameter in the current cycle of measurements from a to more

its meaning in some accidental cycles

Based on the considered operation of the device for forming a numerical equivalent of the measured parameter, it is possible to determine the values of the limiting amplitude of oscillations of the measured parameter, before reaching which the generated numerical equivalent is 5 10 5 20 -25 z o

Aer35

40

45

tapes is stable. It uses the notation

And - measured parameter;

N is the numerical equivalent of the measured parameter Nf – T KA;

f is the frequency of the pulses fed to the input 12; T is the duration of time intervals, information about which is fed to input 11;

K is the proportionality coefficient between the numerical equivalent of the parameter being measured and the parameter measured by the parameter; average value of the Measured parameter, relative to which its oscillations may occur;

some values of the numerical equivalent, which can be fixed by the counter 1, and the corresponding cases, when in the counters 2 and 3 the zero value is fixed;

the values of the measured parameter, which correspond to numerical equivalents;

4N, is the weight of the least significant bit of the counter 1

LC N - N., N,. ,, - N,;

LA, is the increment of the measured parameter, which corresponds to the weight of the least significant bit of counter 1; counter bit weight 2 and 3 I

one

N

1-1

"I; NjH

H,; A; 5A;

i-f

AN, AN ,, - | -4N,;

4A,

increment of the measured parameter, which corresponds to the weight of bits of the counters 2 and 3

AA,

- | - A,

- intermediate numerical equivalents not recorded by the counter 1

N,

N;

-f.

N,., - f4Nj I; -24N.j; N., + 2ftN2 Nj-aN2.

"-.2

The remaining intermediate numerical equivalents are defined by a similar s digit.

the values of the measured parameter, which correspond to intermediate numerical equivalents with the same indices.

-t.i -m

A ;, A; - 2LA, A, -. + 24A A.- ft A,

2 “2

The remaining values of the measured parameter, to which the intermediate numerical equivalents correspond, are determined in the same way.

Using the notation as explained in FIG. In Fig.2, the axis of the values of the measured parameter and the axis of numerical equivalents are combined.

I

For the sake of the situation, when a QHD correction is made, the numerical equivalent formed in the accumulator: W counter 1, i.e. the addition to this unit counter, is composed

Table 1. Table 1 lists the limits within which the value of the measured parameter can be found during the previous measurement cycle and the limits within which the value of the measured parameter can be found in the current measurement cycle. The + sign indicates that the specific situation defined by the table and the number formed in the current measurement cycle in accumulative counter 1 is added to one. The icon indicates that no one is added. When placing icons, upper boundaries are not included in the limits. If two icons are placed in a cage, then in this situation, the addition of the tool itself may or may not occur. It depends on the extent to which the value of the measured parameter was located before it falls within the limits corresponding to the columns. The disclosure of this uncertainty is given in table 2. In table 2, the columns of table. 1, including uncertainty, are presented in two columns. At the top of these columns are the limits within which the measurement can be

parameter before getting to the limits indicated in the top line.

On the basis of the considered operation of the proposed device, it is possible to determine the dependence of the limiting amplitude of oscillations AA „p of the measured parameter on the average value of the measured parameter, to which the generated numerical equivalent is stable.

At А & Аср А; + 0,5 АAj the amplitude of oscillations is maximum

4 A, Ajp

and varies from dA to 0.5 LA.

At 0.5 iAj AcpiAj + dA limiting amplitude

dal

and

4ip

is changing

Asrota 0.5 L A- to & A

2Pri And + iAj i S And; + 1.5 lA the maximum amplitude

A „p A

+ 2

and varies from AAj to 0.5 AA ,.

At А; + 1,5 Л А 6 Аср бА; + 2 А А., amplitude amplitude

 Aoj, cf-A-AA and varies from 0.5 LA / to dA ,.

When A; 4 2iA2.iA, "2.5 dAg, the maximum amplitude of oscillations

LA,

- BUT,

 P 1 + 1 Wed

and varies from iAj to 0.5 AAj

At А; + 2,5 uAj iA.p g А ;, the maximum amplitude of oscillations

LA

f

Asr-A;

2 dA

and varies from 0.5 YES; dodAg.

When A changes in other limits, the pattern of change of LA |, „is repeated.

Fig. 3 graphically shows the character of the change in the relative limiting amplitude of oscillations along the axis of the values of the measured parameter for the proposed device (solid line) and the known device (dotted line).

Thus, the proposed device ensures that there is no change in the generated numerical equivalent of the measured parameter when the measured parameter varies depending on its average value to 1 / 6-1 / 3 of the value corresponding to

the weight of the junior-p yes, which increases the measurement accuracy.

Claims (1)

The formula of the invention and A device for forming a numerical equivalent of the measured parameter, containing a cumulative counter, two elements AND and a trigger (characterized in that, in order to increase the measurement accuracy, two additional counters, a logic unit, a control unit, an OR element and a memory unit, moreover, the counting input of the first additional counter is connected to the output of the OR element, the first input of which is connected to the output of the first element AND and the counting input of the second additional counter, and the second input to the output of the second element AND, the first input of which is connected to the trigger output, perI A; ,,, -г AJ Aj ,, I А. ,, | А..Т А, -, | А. ,, 4 А; ,,,, + 1 Ai -i- A .; A;, L Chg A.-. R - Aj, AI +, A ,,, the second and second setup inputs of which are connected to the outputs of the logic unit, the first and second inputs of which are connected to the outputs of the bits of the second additional counter, the first code of the control unit with the installation inputs of the accumulation counter and the first additional counter, second, third, fourth, fifth and the sixth outputs of the memory block are connected respectively to the installation input of the second additional counter, the third input of the logic unit, the first input of the first element And, the second input of the second element And vhodok mounting block memory signal inputs of which are connected to the outputs of the storage bits of the counter, the control unit input is a first input device and the second input of the first element and - a second input device. Table 1 - + AMa - A ",one Ti-r, f Wi- f, .g. Mifij nm gn M -J- .. - f-h "Hf H, 2 4t Ds / t, 2, / / + 7.2 (7i / 8.2 table 2 .g. Mifij nm -J- .. - f-a "t, 2, / / + ut.if VNIIPI Order 2284/46 Circulation 728 Subscription Random polygons pr-tie, Uzhgorod, st. Project, 4 fpttt.S