RU2575765C1 - Meter of parameters of multi-element passive dipoles - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: device, which comprises a square ware generator, n serially connected inverting integrators that generate pulses of voltage changing according to the law of the first, second, etc. n degree, a differential "current-voltage" converter, (n+1) controlled resistors, one of the outputs of each is connected to the outlet of the square ware generator and outlets of the integrators accordingly, (n+1) analogue switchboards, inlets of which are connected to free outlets of the controlled resistors, outlets of the switchboards are connected to "current-voltage" inlets of the differential converter, n-cascade differentiator on differentiating RC-links, the inlet of the first link is connected to the outlet of the "current-voltage" converter; (n+1) zero indicators (ZI), inlets of each of them are connected accordingly to inlets of the n-th RC-link of the differentiator, (n-1)-th RC-link, etc., with the outlet of the differential converter "current-voltage", additionally the "voltage-current" converter is introduced on the operational amplifier with the parallel negative feedback by voltage and the circuit of the negative feedback by current, the inlet of the converter is connected to the outlet of the (n-1)-th integrator, and the outlet - to the first pole of the measurement facility dipole, the second pole of which is grounded, and to the inlet of the voltage repeater, to the outlet circuit of which a reference resistor is connected, being joined by the second outlet to one of inlets of the differential "current-voltage" converter.

EFFECT: expansion of the device functional capabilities during the measurement of parameters of dipoles with a capacitance element in a circuit break between the poles.

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Description

The invention relates to measuring technique and, in particular, to a technique for measuring the parameters of objects in the form of passive two-terminal devices with lumped parameters having a multi-element equivalent circuit.

A known parameter meter of multi-element passive two-terminal devices (RF patent No. 2144195, G01R 17/10), made in the form of a four-armed electric bridge, in which a voltage pulse shaper of a cubic shape is used for power supply. The inputs of the differential amplifier are included in the measuring diagonal of the bridge, and three differentiators connected in series to the output of the differential amplifier. The outputs of the differentiators, as well as the output of the differential amplifier are connected to the inputs of the zero indicator. The bridge is balanced after the end of transient processes in its circuits, sequentially leading to a zero voltage value at the outputs of the first third, then second and first differentiators and, finally, a differential amplifier. The disadvantages of this bridge meter are:

1) A complex branch circuit with a multi-element bipolar relationship and a multi-element balancing bipolar, which includes adjustable resistors, capacitors and inductors.

2) Bulky analytical expressions for calculating the parameters of the elements of the measured bipolar.

3) Narrow limits of permissible values of the measured parameters.

4) A limited set of options for multi-element two-terminal devices, for which balancing conditions are provided for a specific bridge configuration.

The closest in technical essence to the proposed one is a multi-element passive bipolar parameter meter (RF patent No. 2466412, G01R 17/00), containing a voltage pulse shaper having the form of a function of the nth time degree, which includes a rectangular pulse generator and n series-connected inverting integrators, differential measuring transducer of the difference of currents into voltage, n-cascade differentiator on differentiating RC links, input of the first differentiating RC links but connected to the output of the converter; microprocessor controller (IPC) with (n + 1) measuring channels connected to the outputs of the differentiator and transducer, (n + 1) analog switches, the control inputs of which are connected to the corresponding outputs of the IPC, (n + 1) discretely adjustable resistance resistors included between the outputs of the pulse generator and integrators, on the one hand, and the inputs of analog switches, on the other, the outputs of the switches are connected to the inputs of the current difference to voltage converter. If in the expression for complex conductivity

$Y\left(p\right)=\frac{b_0+b_{\mathrm{one}}p+b_2{p}^2+b_3{p}^3}{a_0+a_{\mathrm{one}}p+a_2{p}^2+a_3{p}^3}$

the values of a ₀ and b _{0 are} not equal to zero, the pulses of the output voltage of the nth integrator, which vary according to the law of the function of the nth degree, excite current pulses in the bipolar of the measurement object with exponents from n to zero, which allows one to determine (n + 1) Y-parameters with indices from zero to n.

The disadvantage of this device is the reduction by at least a unit of the number of measured parameters of capacitive sensors, in the equivalent circuit of which a capacitive element is included in the circuit between the poles, compared to measuring the parameters of two-terminal devices with finite (not zero and not infinite) DC resistance, therefore that in the conductivity formula Y (p) in this case b ₀ = 0 and the parameter Y _{0 is} identically equal to zero, that is, it does not contain information about any element of the two-terminal network. Therefore, it will be necessary to increase the degree of the test voltage pulse, which complicates the equipment. In addition, the measurement errors increase, since the signal level with each subsequent parameter decreases by about an order of magnitude.

The problem to which the invention is directed, is to expand the functionality of the bipolar parameter meter containing a capacitive element in the open circuit between the poles, and to reduce measurement errors.

The technical result is achieved by the fact that in the parameter meter of multi-element passive two-terminal devices containing a rectangular voltage pulse generator, n series-connected inverting integrators, each of which includes an operational amplifier (op-amp), a resistor in the circuit of the inverting input of the op-amp, a parallel capacitor and a discharge key in the feedback circuit of the op-amp, the differential current-voltage converter on the series-connected (n + 1) -th and (n + 2) -th operational amplifiers with parallel negative feedback, the first and second inputs of the converter are connected to the inverting inputs of the (n + 1) th and (n + 2) th op amps, respectively, (n + 1) adjustable resistors, one of the terminals of each of them is connected to the output of the generator pulses and integrator outputs, respectively, of (n + 1) analog switches, the inputs of which are connected to the free terminals of adjustable resistors, the outputs of the switches are connected to the inputs of the current-voltage converter, an n-cascade differentiator on series-connected differentiating RC- venyah, the first link input is connected to the output of inverter "current-voltage"; (n + 1) null indicators (NI), the input of the first of them is connected to the output of the last, n-th RC-link, the input of the second NI is connected to the output of the (n - 1) -th RC-link, etc., the input of the (n + 1) -th NI is connected to the output of the current-voltage converter; the microcontroller, the synchronization output of which is connected to the synchronization input of the pulse generator, additionally introduces a voltage-current converter on the (n + 3) -th operational amplifier with two resistors in the circuit of parallel negative voltage feedback and a reference resistor, the first voltage follower at ( n + 4) -th operational amplifier and resistor divider - in the negative current feedback circuit, the second voltage follower on the (n + 5) -th operational amplifier, the input of which is connected to a common point, is connected the output of the voltage-current converter and the first pole of the two-terminal object of measurement, and an exemplary resistor, one of the terminals of which is combined with the output of the second voltage follower, and the other with the input of the current-voltage converter. The second pole of the bipolar of the measurement object is grounded.

The invention is illustrated by the example of a parameter meter five-element bipolar. The device diagram is shown in FIG. one.

The device contains a generator 1 of rectangular voltage pulses (GUI), four serially connected inverting integrators, each of which includes an operational amplifier (OA) 2, 3, 4 or 5, a resistor 6, 7, 8 or 9 and a capacitor 10, 11, 12 or 13, as well as a bit switch 14, 15, 16 or 17, respectively, a differential current-voltage converter built on the fifth and sixth operational amplifiers 18 and 19, a resistor 20 and 21 are included in the feedback circuit of each of them, respectively, and between the output of the op-amp 18 and the input of the op-amp 19 - a resistor 22, to the lane the outputs of the switches 23, 24, 25, 26 and 27, the inputs of which are connected to adjustable resistors 28, 29, 30, 31 and 32, and the second terminals of the mentioned resistors are connected to the outputs of the generator 1, connected to the second and second inputs of the current-voltage converter the first op-amp 2, the second op-amp 3, the third op-amp 4 and the fourth op-amp 5, respectively. The input of the four-stage differentiator, built on differentiating RC links: capacitors 33, 34, 35 and 36 and resistors 37, 38, 39 and 40, is connected to the output of the current-voltage converter. The outputs of the differentiator are connected to the inputs of the zero indicators (NI): the common terminal of the capacitor 36 and resistor 40 with the input of the first NI 41, the common terminal of the capacitor 35 and the resistor 39 with the input of the second NI 42, the common terminal of the capacitor 34 and the resistor 38 with the input of the third NI 43, the common terminal of the capacitor 33 and the resistor 37 with the input of the fourth NI 44, the input of the fifth NI 45 is connected to the output at converter 'current-voltage ". The input of the synchronization signal of the generator 1 is connected to the synchronization output of the microcontroller 46.

A voltage-to-current converter is additionally introduced into the device circuit at the seventh operational amplifier 47, which is covered by two types of feedback: by the voltage circuit, consisting of resistors 48 and 49, and by the current, by the circuit containing the reference resistor 50, the first voltage follower on the eighth an operational amplifier 51 and a resistor divider 52-53; the second voltage follower at the ninth op-amp 54, the input of which is connected to the output of the voltage-current converter, and the output is to the first output of the reference resistor 55, the second terminal of the latter is connected to one of the inputs of the current-voltage converter. As an example, the equivalent circuit of the five-element two-terminal device of the measurement object contains three series-connected capacitive elements 56, 57 and 58, as well as two resistive elements 59 and 60, with one output of the element 59 connected to the common contact of the elements 56 and 57, and the second output of the element 59 to the grounded contact of the element 58, also one terminal of the element 60 is connected to the common contact of the elements 57 and 58, and the second terminal of the element 60 is connected to the grounded contact of the element 58.

The device operates as follows. Generator 1 generates rectangular voltage pulses of duration t _and with amplitude U ₀ . At the output of the first integrator (OS 2), pulses of linearly varying voltage with amplitude are formed

$$U_{\mathrm{one}}=\frac{U_0{t}_{\text{and}}}{T_{\mathrm{one}}}\text{, (one)}$$

where T ₁ = R ₆ C ₁₀ is the time constant of the first integrator.

The output of the second integrator (OS 3) produces quadratic pulses with amplitude

$$U_2=\frac{U_0{t}_{\mathrm{and}}^2}{2T_{\mathrm{one}}{T}_2},(2)$$

where T ₂ = R ₇ C ₁₁ is the time constant of the second integrator.

The third integrator generates at the output of the op-amp 4 pulses of cubic shape with amplitude

$$U_3=\frac{U_0{t}_{\text{and}}^3}{6T_{\mathrm{one}}{T}_2{T}_3},\text{(3)}$$

where T ₃ = R ₈ C ₁₂ is the time constant of the third integrator.

The fourth integrator generates voltage pulses having the form of a function of the fourth degree of time and an amplitude equal to

$$U_{\mathrm{four}}=\frac{U_0{t}_{\text{and}}^{\mathrm{four}}}{24T_{\mathrm{one}}{T}_2{T}_3{T}_{\mathrm{four}}},\text{(four)}$$

where T ₄ = R ₉ C ₁₃ is the time constant of the fourth integrator.

Cubic current pulses are used to excite a two-terminal C ₅₆ -C ₅₇ -C ₅₈ -R ₅₉ -R ₆₀

$i\left(t\right)=\frac{I_m{t}^3}{t_{\mathrm{and}}^3},$

which forms the voltage-current converter from the output voltage of the third integrator

$i\left(t\right)=\frac{G{U}_3{t}^3}{t_{\mathrm{and}}^3}=\frac{G{U}_0{t}^3}{6T_{\mathrm{one}}{T}_2{T}_3}.$

Here G is the direct transmission conductivity of the converter. It is determined by the elements of the circuit. With a pairwise equality of the resistances R ₅₂ = R ₄₈ , R ₅₃ = R _{49, the} value of G is

$G=-\frac{R_{49}}{R_{48}{R}_{\mathrm{fifty}}}.$

Consequently, the current amplitude of the two-terminal network will be equal to

$I_m=G{U}_3=\frac{G{U}_{0}t{}_{\mathrm{and}}{}^3}{6\cdot T_{\mathrm{one}}{T}_2{T}_3}.\text{(5)}$

An operator image of the complex resistance of a two-terminal device containing a capacitive element 56 in the open circuit between the poles does not contain a free term in the denominator

$$Z\left(p\right)=\frac{\mathrm{one}+p\left[R_{59}{C}_{56}+\left(R_{59}+R_{60}\right)C_{57}+R_{60}{C}_{58}\right]+p^2{R}_{59}{R}_{60}\left(C_{56}{C}_{57}+C_{56}{C}_{58}+C_{57}{C}_{58}\right)}{p{C}_{56}+p^2\left[\left(R_{59}+R_{60}\right)C_{56}{C}_{57}+R_{60}{C}_{56}{C}_{58}\right]+p^3{R}_{59}{R}_{60}{C}_{56}{C}_{57}{C}_{58}}$$

If the operator p is taken out of the denominator, the resulting expression contains the product of the 1 / p operator, which corresponds to the additional operation of integrating the test signal and the modified operator image of the complex resistance of the two-terminal network:

$$Z\left(p\right)=\frac{\mathrm{one}}{p}\cdot \frac{\mathrm{one}+p\left[R_{59}{C}_{56}+\left(R_{59}+R_{60}\right)C_{57}+R_{60}{C}_{58}\right]+p^2{R}_{59}{R}_{60}\left(C_{56}{C}_{57}+C_{56}{C}_{58}+C_{57}{C}_{58}\right)}{C_{56}+p\left[\left(R_{59}+R_{60}\right)C_{56}{C}_{57}+R_{60}{C}_{56}{C}_{58}\right]+p^2{R}_{59}{R}_{60}{C}_{56}{C}_{57}{C}_{58}}$$

 Therefore, the reaction of a two-terminal to a cubic current pulse will contain voltage pulses on the two-terminal not only of the 3rd, 2nd, 1st and zero degrees, but also a component of the 4th degree:

$$u_{dP}\left(t\right)=\frac{Z_{-\mathrm{one}}{I}_m{t}^{\mathrm{four}}}{\mathrm{four}{t}_{\mathrm{and}}^3}+\frac{Z_0{I}_m{t}^3}{t_{\mathrm{and}}^3}+\frac{3\cdot Z_{\mathrm{one}}{I}_m{t}^2}{t_{\mathrm{and}}^3}+\frac{6\cdot Z_2{I}_{m}t}{t_{\mathrm{and}}^3}+\frac{6\cdot Z_3{I}_m}{t_{\mathrm{and}}^3}(6)$$

The amplitudes of all five components of the voltage pulses at the two-terminal are determined by the generalized parameters of the resistance of the two-terminal (Z-parameters). In particular, for the C ₅₆ -C ₅₇ -C ₅₈ -R ₅₉ -R ₆₀ five-element two-terminal network considered as an example, these parameters are equal

$$Z_{-\mathrm{one}}=\frac{\mathrm{one}}{C_{56}};$$

$$Z_0=R_{59};$$

$$Z_{\mathrm{one}}=-R_{59}^2{C}_{57};$$

$$Z_2=R_{59}^2\left(R_{59}+R_{60}\right)C_{57}^2;$$

$$Z_3=-R_{59}^2{C}_{57}^2\left[{\left(R_{59}+R_{60}\right)}^2{C}_{57}+R_{59}^2{C}_{58}\right]$$

By measuring the amplitudes of all five components of the voltage (6), it is possible to calculate the values of Z-parameters, and then the electrical quantities — capacitances C ₅₆ , C ₅₇ and C ₅₈ and resistance R ₅₉ and R ₆₀ . Measurements of Z-parameters are carried out by balancing all components of the current created by voltage (6) through the model resistor 55 with current pulses in the form of power functions with exponents from fourth to zero. First, the currents of the highest, fourth, degree are balanced. The amplitude of the current pulse of the two-terminal I ₄ is determined by the amplitude of the voltage pulse (6) of the same form U _{DP 4} :

$$I_{\mathrm{four}}=\frac{U_{dP\mathrm{.four}}}{R_{55}}=\frac{Z_{-\mathrm{one}}{I}_m{t}_{\mathrm{and}}}{\mathrm{four}\cdot R_{55}}=\frac{Z_{-\mathrm{one}}G{U}_0{t}_{\mathrm{and}}^{\mathrm{four}}}{24\cdot T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}(7)$$

The amplitude of the balancing current of the 4th degree is regulated by a resistor 32:

$$I_{\mathrm{at}R\mathrm{four}}=\frac{U_{\mathrm{four}}}{R_{32}}=\frac{U_{0}t{}_{\mathrm{and}}{}^{\mathrm{four}}}{24\times T_{\mathrm{one}}{T}_2{T}_3{T}_{\mathrm{four}}{R}_{32}}(8)$$

The output voltage of the current-voltage converter u _PNT at the output of the OS 19 is proportional to the difference of the input currents I _{in 1} and I _{in 2} . If the resistance of the resistors 20 and 22 is equal, the voltage u _PNT = (I _{in 1} - I _{in 2} ) R ₂₁ . When currents (7) and (8) are reached, the pulse voltage with a flat top at the output of the fourth stage of the differentiator after the transition in the two-terminal network becomes zero, which is controlled by the first zero indicator 41. The equilibrium condition has the form

$$\frac{Z_{-\mathrm{one}}G}{R_{55}}=\frac{\mathrm{one}}{T_{\mathrm{four}}{R}_{32}}$$

whence find the value of the parameter Z _-1 :

$$Z_{-\mathrm{one}}=\frac{R_{55}}{G{T}_{\mathrm{four}}{R}_{32}}.(9)$$

Then carry out the balancing of the pulses of the currents of a cubic shape. The amplitude of the current I _{3 of the} two-terminal network depends on the cubic component of the voltage pulse on the two-terminal terminal U _{dp 3} :

$$I_3=\frac{U_{dP.3}}{R_{55}}=\frac{Z_0{I}_m}{R_{55}}=\frac{Z_{0}G{U}_0{t}_{\mathrm{and}}^3}{6\cdot T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}(10)$$

The amplitude of the balancing current is regulated by a resistor 31:

$$I_{\mathrm{at}R3}=\frac{U_3}{R_{31}}=\frac{U_{0}t{}_{\mathrm{and}}{}^3}{6\cdot T_{\mathrm{one}}{T}_2{T}_3{R}_{31}}(\mathrm{eleven})$$

The equilibrium condition has the form

$$\frac{Z_{0}G}{R_{55}}=\frac{\mathrm{one}}{R_{31}}$$

where do they find the value of the parameter Z ₀ :

$$Z_0=\frac{R_{55}}{G{R}_{31}}.(12)$$

At the third stage, the impulses of the currents are quadratic balanced. The amplitude of the current I _{2 of the} two-terminal network depends on the quadratic component of the voltage pulse on the two-terminal network U _{dp 2} :

$$I_2=\frac{U_{dP.2}}{R_{55}}=\frac{Z_{\mathrm{one}}G{U}_0{t}_{\mathrm{and}}^2}{2\cdot T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}(13)$$

The amplitude of the balancing current is regulated by a resistor 30:

$$I_{\mathrm{at}R2}=\frac{U_2}{R_{\mathrm{thirty}}}=\frac{U_{0}t{}_{\mathrm{and}}{}^2}{2\cdot T_{\mathrm{one}}{T}_2{R}_{\mathrm{thirty}}}(\mathrm{fourteen})$$

The equilibrium condition has the form

$$\frac{Z_{\mathrm{one}}G}{T_3{R}_{55}}=\frac{\mathrm{one}}{R_{\mathrm{thirty}}}$$

whence determine the value of the parameter Z ₁ :

$$Z_{\mathrm{one}}=\frac{T_3{R}_{55}}{G{R}_{\mathrm{thirty}}}.(\mathrm{fifteen})$$

At the fourth stage, balancing the pulses of the currents of a linear form is performed. The amplitude of the current I ₁ is determined by the two-terminal voltage pulse amplitude on a linear two-terminal network component U _{dn 1:}

$$I_{\mathrm{one}}=\frac{U_{dP\mathrm{one}}}{R_{55}}=\frac{Z_{2}G{U}_0{t}_{\mathrm{and}}}{T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}(16)$$

The amplitude of the balancing current is regulated by a resistor 29:

$$I_{\mathrm{at}R\mathrm{one}}=\frac{U_{\mathrm{one}}}{R_{\mathrm{29th}}}=\frac{U_0{t}_{\mathrm{and}}}{T_{\mathrm{one}}{R}_{\mathrm{29th}}}(17)$$

The equilibrium condition has the form

$$\frac{Z_{2}G}{T_2{T}_3{R}_{55}}=\frac{\mathrm{one}}{R_{\mathrm{29th}}}$$

where do they find the value of parameter Z ₂ :

At the fifth stage, balancing of the DC pulses is performed. The amplitude of the current I ₀ two-terminal is determined by the amplitude of the component of the voltage pulse on the two-terminal U _{dp 0} :

$$I_0=\frac{U_{dP0}}{R_{55}}=\frac{Z_{3}G{U}_0}{T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}(19)$$

The amplitude of the balancing current is regulated by a resistor 28:

$$I_{\mathrm{at}R0}=\frac{U_0}{R_{28}}(\mathrm{twenty})$$

The equilibrium condition has the form

$$\frac{Z_{3}G}{T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}=\frac{\mathrm{one}}{R_{28}}$$

where determine the value of the parameter Z ₃ :

$$Z_3=\frac{T_{\mathrm{one}}{T}_2{T}_3{R}_{55}}{G{R}_{28}}.(21)$$

Another example of a five-element bipolar can be an object, the equivalent circuit of which is shown in FIG. 2. The five-element two-terminal device of the measurement object consists of a series-connected first capacitive element 61, a first resistive element 62 and an inductive element 63, in parallel with which a second resistive element 64 and a second capacitive element 65 are connected. The first pole of the two-terminal device is connected to the output of the voltage-current converter, the second pole is grounded.

An operator image of the complex resistance of a two-terminal device containing a capacitive element 61 in the open circuit between the poles does not contain a free term in the denominator

$$Z\left(p\right)=\frac{R_{64}+p\left(R_{62}{R}_{64}{C}_{61}+L_{63}\right)+p^2\left[\left({\mathrm{<figure-callout\; id="62"\; label="R"\; filenames="00000047.png"\; state="\{\{state\}\}">R</figure-callout>}}_{62}+R_{64}\right)L_{63}{C}_{61}+R_{64}{L}_{63}{C}_{65}\right]+p^3{R}_{62}{R}_{64}{L}_{63}{C}_{61}{C}_{65}}{p{R}_{64}{C}_{61}+p^2{L}_{63}{C}_{61}+p^3{R}_{64}{L}_{63}{C}_{61}{C}_{65}}$$

The modified operator image of the complex resistance of the two-terminal network has the form

И в этом случае реакция двухполюсника на кубический импульс тока будет содержать импульсы напряжения на двухполюснике не только 3-й, 2-й, 1-й и нулевой степени, но и составляющую 4-й степени: $$Z\left(p\right)=\frac{R_{64}+p\left(R_{62}{R}_{64}{C}_{61}+L_{63}\right)+p^2\left[\left({\mathrm{<figure-callout\; id="62"\; label="R"\; filenames="00000047.png"\; state="\{\{state\}\}">R</figure-callout>}}_{62}+R_{64}\right)L_{63}{C}_{61}+R_{64}{L}_{63}{C}_{65}\right]+p^3{R}_{62}{R}_{64}{L}_{63}{C}_{61}{C}_{65}}{R_{64}{C}_{61}+p{L}_{63}{C}_{61}+p^2{R}_{64}{L}_{63}{C}_{61}{C}_{65}}$$

And in this case, the reaction of a two-terminal to a cubic current pulse will contain voltage pulses on the two-terminal not only of the 3rd, 2nd, 1st and zero degrees, but also a component of the 4th degree:

$$u_{\text{dp}}\left(t\right)=\frac{Z_{-\mathrm{one}}{I}_{\text{m}}{t}^{\mathrm{four}}}{\mathrm{four}{t}_{\text{and}}^3}+\frac{Z_0{I}_{\text{m}}{t}^3}{t_{\text{and}}^3}+\frac{3\cdot Z_{\mathrm{one}}{I}_{\text{m}}{t}^2}{t_{\text{and}}^3}+\frac{6\cdot Z_2{I}_{\text{m}}t}{t_{\text{and}}^3}+\frac{6\cdot Z_3{I}_{\text{m}}}{t_{\text{and}}^3}$$

Generalized bipolar resistance parameters (Z-parameters) are equal

$$Z_{-\mathrm{one}}=\frac{\mathrm{one}}{C_{61}};$$

$$Z_0={\mathrm{<figure-callout\; id="62"\; label="R"\; filenames="00000047.png"\; state="\{\{state\}\}">R</figure-callout>}}_{62};$$

$$Z_{\mathrm{one}}={\mathrm{<figure-callout\; id="63"\; label="L"\; filenames="00000047.png"\; state="\{\{state\}\}">L</figure-callout>}}_{63};$$

$$Z_2=-\frac{{\mathrm{<figure-callout\; id="63"\; label="L"\; filenames="00000047.png"\; state="\{\{state\}\}">L</figure-callout>}}_{63}^2}{R_{64}};$$

$$Z_3=\frac{{\mathrm{<figure-callout\; id="63"\; label="L"\; filenames="00000047.png"\; state="\{\{state\}\}">L</figure-callout>}}_{63}^3}{R_{64}^2}-{\mathrm{<figure-callout\; id="63"\; label="L"\; filenames="00000047.png"\; state="\{\{state\}\}">L</figure-callout>}}_{63}^2{C}_{65}.$$

As can be seen from the above examples, to measure the five parameters of a two-terminal device with a capacitive element in the open circuit between the poles, a test current pulse of the third degree is sufficient, which indicates a simplification of the equipment. The device has the property of separate balancing. The formulas for calculating two-terminal parameters are simple. The measurement results are stable, as they are determined by the stability of the resistors and capacitors that are part of the integrators, and adjustable resistors. It is also suitable for measuring the parameters of two-terminal devices of a general form with a finite, i.e., with non-zero and non-infinite resistance between the poles at constant current.

Information sources

1. RF patent No. 2144195, G01R 17/10. Bridge meter of parameters of multi-element passive two-terminal / V.I. Ivanov, G.I. Peredelsky, publ. 01/10/2000. Bull. Number 1.

2. RF patent No. 2466412, G01R 17/00. Parameter meter for multi-element passive bipolar / V.I. Ivanov, publ. 06/10/2012. Bull. No. 16. (Prototype).

3. Ivanov, V.I. The use of generalized parameters of the measuring circuit for the identification of multi-element bipolar / V.I. Ivanov, V.S. Titov, D.A. Golubov // Sensors and systems. - 2010. - No. 8. - S. 43-45.

4. Ivanov V.I. Transformation of the parameters of multi-element RLC two-terminal circuits with short circuit and open circuit between poles on a direct current / V.I. Ivanov, V.S. Titov // Sensors and systems. 2014. No9. S. 26-32.

Claims (1)

A multi-element passive two-terminal parameter meter containing a rectangular voltage pulse generator, n serially connected inverting integrators, each of which includes an operational amplifier (op-amp), a resistor in the op-amp inverting input circuit, a capacitor and a discharge key in the op-amp feedback circuit, parallel differential a current-voltage converter on serially connected (n + 1) -th and (n + 2) -th operational amplifiers with parallel negative feedback, the first and the second inputs of the converter are connected to the inverting inputs of the (n + 1) th and (n + 2) th op amps, respectively, (n + 1) adjustable resistors, one of the outputs of each of them is connected to the output of the pulse generator and the outputs of the integrators, respectively, ( n + 1) analog switches, the inputs of which are connected to the free terminals of adjustable resistors, the outputs of the switches are connected to the inputs of the current-voltage converter, an n-cascade differentiator on series differentiating RC links, the input of the first link is connected to the output current-voltage converter; (n + 1) null indicators (NI), the input of the first of them is connected to the output of the last, n-th RC-link of the differentiator, the input of the second NI - to the output of the (n - 1) -th RC-link, etc. , the input of the (n + 1) -th NI is connected to the output of the current-voltage converter; a microcontroller, the synchronization output of which is connected to the synchronization input of the pulse generator, characterized in that it additionally includes a voltage-current converter on the (n + 3) -th operational amplifier with two resistors in a parallel circuit with negative voltage feedback and a reference resistor , the first voltage follower on the (n + 4) -th operational amplifier and the resistor divider - in the negative current feedback circuit, the second voltage follower on the (n + 5) -th operational amplifier, the input of which is connected is connected to the common connection point of the output of the voltage-current converter and the first pole of the two-terminal device of the measurement object, as well as a model resistor, one output of which is connected to the output of the second voltage follower, and the second to the input of the current-voltage converter; the second pole of the bipolar of the measurement object is grounded.

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