RU2542904C2 - Self-tuning electric drive - Google Patents

Abstract

FIELD: electricity.

SUBSTANCE: invention refers to electric drives and may be used to make control systems. Self-tuning electric drive comprises serial summators, correction device to correct value of electric drive error, amplifier, motor and reduction gear with position sensor installed on its output shaft, quad unit, divider and multiplier units, constant signal sources, integrator, sinusoidal functional converter, amplitude setter, rooting unit.

EFFECT: improved operational speed of the electric drive without excessive preset dynamic error at the valid amplitude of input harmonic signal considering inductance of its armature circuit.

2 dwg

Description

The invention relates to electric drives and can be used to create their control systems.

A self-adjusting electric drive is known comprising a first adder in series, a correcting device, an amplifier, an electric motor with a reducer, on the output shaft of which a position sensor is installed, the output of which is connected to the first input of the first adder, in series, an amplitude adjuster, a quadrator, a division unit, the second input of which is connected to the output of the first constant signal source, the second adder, the first square root extraction unit, the third adder, the second input of which is connected to the output of the second constant signal source and the second input of the second adder, the second square root extraction unit, an integrator, a sine function converter and a multiplication unit, the second input of which is connected to the output of the amplitude adjuster, and the output to the second input of the first adder (see RF patent No. 2399080, Bull. No. 25, 2010).

The disadvantage of this device is that due to the approximation of the description of the used amplitude-frequency characteristics, it does not provide the maximum speed of the electric drive, if the inductance of its anchor circuit cannot be neglected.

A self-adjusting electric drive is also known, comprising a first adder in series, a correcting device, an amplifier, an electric motor with a gearbox, on the output shaft of which a position sensor is installed, the output of which is connected to the first input of the first adder, a quadrator connected in series, the first division unit, the second input of which is connected to the output of the first constant signal source, and the second adder, the integrator connected in series, the sine functional converter, the first the first multiplication unit, the second input of which is connected to the output of the amplitude setter, and the output - to the second input of the first adder, the second constant signal source and the third adder connected in series, the second multiplication unit connected in series, the first input of which is connected to the quad output and the first inputs of the fourth, the fifth and sixth adders, the third multiplication unit, the second division unit, the square root extraction unit, the seventh adder, the second input of which is connected to the output of the amplitude adjuster and the second input the third adder, the fourth multiplication unit and the eighth adder, the second input of which is connected to the output of the third adder and the input of the quadrator, and the output to the integrator input, the fifth multiplication unit connected in series, the first and second inputs of which are connected, respectively, to the outputs of the second adder and unit square root extraction, and the third division block, the output of which is connected to the second input of the fourth multiplication block, and the second input to the output of the first constant signal source, to the second inputs of the fourth, fifth and the sixth adder and the first inputs of the fourth, fifth and sixth division blocks, the second input of the fourth division block connected to the output of the fifth adder and the second input of the second multiplication block, the second input of the fifth division block to the output of the sixth adder and the second input of the third multiplication block, the second the input of the sixth division unit is to the output of the fourth adder and the second input of the second division unit, and the output is to the second input of the second adder, the third and fourth inputs of which are connected, respectively, to the outputs of the fourth and fifth addition of division blocks (see RF patent No. 2450300, bull. No. 13, 2012).

The specified device in its technical essence is the closest to the proposed invention and is taken as a prototype. Its disadvantage is that it does not allow to preserve the given dynamic accuracy when changing the amplitude of the driving harmonic signal of the electric drive, if the inductance of its anchor circuit cannot be neglected.

The task to which the claimed technical solution is directed is to ensure the maximum possible speed of the electric drive, taking into account the inductance of its anchor circuit when changing the amplitude of the input harmonic signal without reducing the specified dynamic accuracy.

The technical result that can be obtained by implementing the proposed technical solution is expressed in the formation of an additional self-tuning circuit, in which the maximum possible value of the input signal frequency is formed, and therefore the maximum possible speed of the electric drive without exceeding the specified dynamic error at the current amplitude of the input harmonic signal and taking into account the inductance of its anchor chain.

The problem is solved in that in a self-adjusting electric drive containing a first adder in series, a correction device, an amplifier, an electric motor with a gearbox, on the output shaft of which a position sensor is installed, the output of which is connected to the first input of the first adder, a quadrator, a first division unit are connected in series, the second input of which is connected to the output of the first constant signal source, and the second adder, series-connected integrator, sine functional the first converter and the first multiplication unit, the second input of which is connected to the output of the amplitude adjuster, and the output - to the second input of the first adder, the second constant signal source and the third adder connected in series, the second multiplication unit connected in series, the first input of which is connected to the quad output and the first the inputs of the fourth, fifth and sixth adders, the third multiplication unit, the second division unit, the square root extraction unit, the seventh adder, the second input of which is connected to the output of the setter the plates and the second input of the third adder, the fourth multiplication unit and the eighth adder, the second input of which is connected to the output of the third adder and the input of the quadrator, and the output to the integrator input, the fifth multiplication unit connected in series, the first input of which is connected to the output of the second adder, and the third the division unit, the second input of which is connected to the output of the first constant signal source, to the second inputs of the fourth, fifth and sixth adders and to the first inputs of the fourth, fifth and sixth division units, and the output to the third input of the fourth multiplication block, the second inputs of the fourth and fifth division blocks connected, respectively, to the outputs of the fifth and sixth adders, the second input of the sixth division block connected to the output of the fourth adder and the second input of the second division block, and its output to the second input of the second the adder, the third and fourth inputs of which are connected, respectively, to the outputs of the fourth and fifth blocks of division, additionally introduced sequentially connected ninth adder, the first input of which is connected to the output a quadrator, and a seventh division unit, the second input of which is connected to the output of the first constant signal source and the second input of the ninth adder, and the output to the fifth input of the second adder, as well as the sixth multiplication unit, the first and second inputs of which are connected, respectively, to the outputs of the fifth and the ninth adder, and the output is to the second input of the third multiplication unit, and the seventh multiplication unit, the first input of which is connected to the output of the square root extraction unit, the second input to the output of the third adder, and the output to the second input fifth multiplier.

A comparative analysis of the essential features of the proposed technical solution with the essential features of the analogue and the prototype indicates its compliance with the criterion of "novelty", these essential features do not explicitly follow from the prior art, i.e. the proposed technical solution meets the criterion of "inventive step" and is industrially applicable.

In this case, the distinguishing features of the claims provide the highest possible speed of the electric drive, taking into account the inductance of its anchor circuit, while maintaining a given dynamic control accuracy when changing the amplitude of the input harmonic signal.

; F (с абсциссой $${\omega }_p^0$$

), G, Н - точки пересечения горизонтальной прямой, имеющей ординату A_p/ε₁, с АЧХ 1, секущей 2 и касательной 3, соответственно; A(ω_min), A( $${\omega }_p^{*}$$

), A(ω_mах) - значения АЧХ на частотах ω_min, $${\omega }_p^{*}$$

и ω_max, соответственно.Figure 1 shows the structural diagram of a self-adjusting electric drive, and figure 2 - objects that explain the features and operation of the proposed device. The following designations are introduced in these drawings: α- angle of rotation of the output shaft of the gearbox; α _ВХ - a setting (input) harmonic signal supplied to the input of the electric drive; And _p , ω _p - the amplitude and frequency of the signal α _BX , respectively; ε = α _BX -α and ε ₁ - respectively, the error of the electric drive and the set allowable value of its dynamic error; [ω _min , ω _max ] is the range of variation of the working frequencies of the input signal; U *, U, respectively, the amplified signal and the control signal of the electric motor 4. The number 1 in figure 2 indicates the amplitude-frequency characteristic (AFC) of the drive in question; number 2 - secant, connecting points A and B on this frequency response; and the number 3 is the tangent to the frequency response at point C with an abscissa $${\omega }_p^{*}$$

; F (with abscissa $${\omega }_p^0$$

), G, Н - the intersection points of the horizontal line with the ordinate A _p / ε ₁ , with frequency response 1, secant 2 and tangent 3, respectively; A (ω _min ), A ( $${\omega }_p^{*}$$

), A (ω _max ) - frequency response at frequencies ω _min , $${\omega }_p^{*}$$

and ω _max , respectively.

The self-adjusting electric drive contains a series-connected first adder 1, a correction device 2, an amplifier 3, an electric motor 4 with a gear 5, on the output shaft of which a position sensor 6 is installed, the output of which is connected to the first input of the first adder 1, the quadrator 7 connected in series, the first division unit 8 , the second input of which is connected to the output of the first source 9 of the constant signal, and the second adder 10, connected in series to the integrator 11, the sine functional Converter 12 and the first a multiplication unit 13, the second input of which is connected to the output of the amplitude setter 14, and the output is connected to the second input of the first adder 1, the second constant signal source 15 and the third adder 16 connected in series to the second multiplication unit 17, the first input of which is connected to the quad output 7 and the first inputs of the fourth 18, fifth 19 and sixth 20 adders, the third multiplication unit 21, the second division unit 22, the square root extraction unit 23, the seventh adder 24, the second input of which is connected to the output of the amplitude adjuster 14 there and the second input of the third adder 16, the fourth multiplication unit 25 and the eighth adder 26, the second input of which is connected to the output of the third adder 16 and the input of the quadrator 7, and the output to the input of the integrator 11, connected in series to the fifth multiplication unit 27, the first input of which is connected to the output of the second adder 10, and the third division unit 28, the second input of which is connected to the output of the first constant signal source 9, to the second inputs of the fourth 18, fifth 19 and sixth 20 adders and to the first inputs of the fourth 29, fifth 30 and sixth 31 blocks division, and the output to the second input of the fourth block 25 of multiplication, and the second inputs of the fourth 29 and fifth 30 blocks of division are connected, respectively, to the outputs of the fifth 19 and sixth 20 adders, the second input of the sixth block 31 division is connected to the output of the fourth adder 18 and the second the input of the second division unit 22, and its output to the second input of the second adder 10, the third and fourth inputs of which are connected, respectively, to the outputs of the fourth 29 and fifth 30 of the division units, the ninth adder 32, the first input of which is connected in series connected to the output of the quadrator 7, and the seventh division unit 33, the second input of which is connected to the output of the first constant signal source 9 and the second input of the ninth adder 32, and the output to the fifth input of the second adder 10, as well as the sixth multiplication unit 34, the first and second the inputs of which are connected, respectively, to the outputs of the fifth 19 and ninth 32 adders, and the output to the second input of the third multiplication block 21, and the seventh multiplication block 35, the first input of which is connected to the output of the square root extraction unit 23, the second input to the output of the third from ummatora 16, and the output to the second input of the fifth block 27 of the multiplication. Management Object 36.

Self-adjusting electric drive operates as follows. The error signal 8 at the output of the adder 1, the first negative (from the sensor 6 side) and second positive inputs of which have unit gains, after correction in block 2, amplifying, is fed to the input of electric motor 4, bringing its shaft into rotational motion with direction and speed (acceleration), depending on the incoming signal U. As you know, the value of the error ε with the installed correction device 2 with a constant structure and constant parameters will increase with increasing load on the drive , i.e. when the amplitude A _r and frequency ω _{r of the} input signal α _VX change. If at the current value of A _{p the} value of ε becomes less than the permissible ε ₁ , then it is possible to increase ω _p , and therefore the speed (productivity) of the electric drive within the specified dynamic accuracy.

=k_H(A_p/ε₁-A(ω_min))+ω_min, а на выходе квадратора 7 - сигнал $${\omega }_p^{*2}$$

(где k_H=(ω_mах-ω_min)/(A(ω_max)-A(ω_min))).At the output of setter 14, a signal A _r is generated, at the output of source 9, a single signal, and at the output of source 15, a signal equal to ω _min - k _H A (ω _min ). The first (from the source 15) and second positive inputs of the adder 16, respectively, have a unity gain and gain equal to k _H / ε ₁ . As a result, a signal is generated at its output. $${\omega }_p^{*}$$

= k _H (A _p / ε ₁ -A (ω _min )) + ω _min , and at the output of quadrator 7, the signal $${\omega }_p^{*2}$$

(where k _H = (ω _max- ω _min ) / (A (ω _max ) -A (ω _min ))).

соответственно, а их вторые положительные входы - единичные коэффициенты усиления. В результате на выходе блока 23 формируется сигнал $$\sqrt{\left(1+{\omega }_p^{*2}{T}_1^2\right)/\left({\omega }_p^{*2}\left(1+{\omega }_p^{*2}{T}_2^2\right)\left(1+{\omega }_p^{*2}{T}_3^2\right)\left(1+{\omega }_p^{*2}{T}_4^2\right)\right)}.$$

The first positive inputs of the adders 18, 19, 20 and 32 (from the side of the quadrator 7) have gains $$T_{\mathrm{one}}^2,{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2,{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2,T_{\mathrm{four}}^2,$$

respectively, and their second positive inputs are unity gain. As a result, a signal is generated at the output of block 23 $$\sqrt{\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2\right)/\left({\omega }_p^{*2}\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{four}}^2\right)\right)}.$$

The first (from the side of block 23) negative input of the adder 24 has a gain equal to K, and the second positive one has a gain of 1 / ε ₁ . As a result, a signal is generated at its output. $$A_p/{\epsilon }_{\mathrm{one}}-K\sqrt{\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2\right)/\left({\omega }_p^{*2}\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{four}}^2\right)\right).}$$

Первый (со стороны блока 8), третий (со стороны блока 29), четвертый (со стороны блока 30) и пятый (со стороны блока 33) отрицательные входы сумматора 10 имеют коэффициенты усиления, равные 1, $$T_1^2,T_2^2,T_3^2\text{ и }{T}_4^2,$$

соответственно, а второй положительный вход (со стороны блока 31) - коэффициент усиления $$T_1^2.$$

В результате на выходе сумматора 10 формируется сигнал $$\frac{T_1^2}{1+{\omega }_p^{*2}{T}_1^2}\text{ - }\frac{\text{1}}{{\omega }_{\text{p}}^{\text{*2}}}\text{ - }\frac{{\text{T}}_{\text{2}}^{\text{2}}}{\text{1}+{\omega }_{\text{p}}^{\text{*2}}{T}_2^2}\text{ - }\frac{{\text{T}}_{\text{3}}^{\text{2}}}{\text{1}+{\omega }_{\text{p}}^{\text{*2}}{T}_3^2}\text{ - }\frac{{\text{T}}_{\text{4}}^{\text{2}}}{\text{1}+{\omega }_{\text{p}}^{\text{*2}}{T}_4^2},$$

a на выходе блока 28 - сигнал $${\left[\sqrt{\frac{1+{\omega }_p^{*2}{T}_1^2}{\left(1+{\omega }_p^{*2}{T}_2^2\right)\left(1+{\omega }_p^{*2}{T}_3^2\right)\left(1+{\omega }_p^{*2}{T}_4^2\right)}}\left(\frac{T_1^2}{1+{\omega }_p^{*2}{T}_1^2}\text{ - }\frac{\text{1}}{{\omega }_{\text{p}}^{\text{*2}}}\text{ - }\frac{{\text{T}}_{\text{2}}^{\text{2}}}{\text{1}+{\omega }_{\text{p}}^{\text{*2}}{T}_2^2}\text{ - }\frac{{\text{T}}_{\text{3}}^{\text{2}}}{\text{1}+{\omega }_{\text{p}}^{\text{*2}}{T}_3^2}\text{ - }\frac{{\text{T}}_{\text{4}}^{\text{2}}}{\text{1}+{\omega }_{\text{p}}^{\text{*2}}{T}_4^2}\right)\right]}^{-1}.$$

Первый (со стороны блока 25) и второй положительные входы сумматора 26 имеют коэффициенты усиления, равные 1/К и 1, соответственно. В результате, на его выходе формируется сигналAt the outputs of blocks 8, 29, 30, 31 and 33, respectively, signals are generated $$\mathrm{one}/{\omega }_p^{*2},\text{one/}\left(\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2\right),\text{one/}\left(\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\right),\text{one/}\left(\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{T}_{\mathrm{one}}^2\right),\text{one/}\left(\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{T}_{\mathrm{four}}^2\right).$$

The first (from the side of block 8), the third (from the side of block 29), the fourth (from the side of block 30) and the fifth (from the side of block 33) the negative inputs of the adder 10 have gains equal to 1, $$T_{\mathrm{one}}^2,{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2,{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\text{and}{T}_{\mathrm{four}}^2,$$

respectively, and the second positive input (from the side of block 31) is the gain $$T_{\mathrm{one}}^2.$$

As a result, a signal is generated at the output of the adder 10 $$\frac{T_{\mathrm{one}}^2}{\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2}\text{-}\frac{\text{one}}{{\omega }_{\text{p}}^{\text{* 2}}}\text{-}\frac{{\text{<figure-callout id="2" label="T" filenames="00000027.png" state="{{state}}">T</figure-callout>}}_{\text{2}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2}\text{-}\frac{{\text{<figure-callout id="3" label="T" filenames="00000027.png" state="{{state}}">T</figure-callout>}}_{\text{3}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2}\text{-}\frac{{\text{T}}_{\text{four}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{T}_{\mathrm{four}}^2},$$

a at the output of block 28 is a signal $${\left[\sqrt{\frac{\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2}{\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{four}}^2\right)}}\left(\frac{T_{\mathrm{one}}^2}{\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2}\text{-}\frac{\text{one}}{{\omega }_{\text{p}}^{\text{* 2}}}\text{-}\frac{{\text{<figure-callout id="2" label="T" filenames="00000027.png" state="{{state}}">T</figure-callout>}}_{\text{2}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2}\text{-}\frac{{\text{<figure-callout id="3" label="T" filenames="00000027.png" state="{{state}}">T</figure-callout>}}_{\text{3}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2}\text{-}\frac{{\text{T}}_{\text{four}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{T}_{\mathrm{four}}^2}\right)\right]}^{-\mathrm{one}}.$$

The first (from the side of block 25) and the second positive inputs of the adder 26 have gains equal to 1 / K and 1, respectively. As a result, a signal is generated at its output.

$${\omega }_p={\left[K\sqrt{\frac{\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2}{\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{four}}^2\right)}}\left(\frac{T_{\mathrm{one}}^2}{\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2}\text{-}\frac{\text{one}}{{\omega }_{\text{p}}^{\text{* 2}}}\text{-}\frac{{\text{<figure-callout id="2" label="T" filenames="00000027.png" state="{{state}}">T</figure-callout>}}_{\text{2}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2}\text{-}\frac{{\text{<figure-callout id="3" label="T" filenames="00000027.png" state="{{state}}">T</figure-callout>}}_{\text{3}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2}\text{-}\frac{{\text{T}}_{\text{four}}^{\text{2}}}{\text{one}+{\omega }_{\text{p}}^{\text{* 2}}{T}_{\mathrm{four}}^2}\right)\right]}^{-\mathrm{one}}\times$$

$$\times (A_p/{\epsilon }_{\mathrm{one}}-K\sqrt{\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{one}}^2\right)/\left({\omega }_p^{*2}\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2\right)\left(\mathrm{one}+{\omega }_p^{*2}{T}_{\mathrm{four}}^2)\right)\right)}+{\omega }_p^{*},\text{(one)}$$

determining the frequency ω _p , providing the maximum possible speed of harmonic motion of the electric drive with an error not exceeding ε ₁ .

At the output of the integrator 11 having a unity gain, a signal ω _p t is formed, and at the output of the functional converter 12, a signal sinω _p t is generated. As a result, at the output of block 13

the desired harmonic signal is formed α _in = A _p sinω _p t with a given amplitude A _p and an automatically generated frequency ω _p , which ensures the maximum possible speed of the electric drive taking into account its inductance (for given values of ε ₁ and А _p ).

To clarify this fact, we note that the corrective device 2, which ensures the stability of the considered electric drive, has the form:

$$W_k(S)=\frac{T_{\mathrm{one}}S+\mathrm{one}}{T_{2}S+\mathrm{one}},$$

where T ₁ > T ₂ = const, T ₁ = 1 / ω _cp = const, ω _cp is the cutoff frequency of the amplitude-frequency characteristic (AFC) of the electric drive. As a result, the transfer function of the direct circuit of this electric drive, taking into account the specified correction device, has the form:

$$W(S)=\frac{K(T_{\mathrm{one}}S+\mathrm{one})}{S\left(T_{2}S+\mathrm{one}\right)\left(T_{3}S+\mathrm{one}\right)\left(T_{\mathrm{four}}S+\mathrm{one}\right)},$$

and its frequency response is:

$$A\left(\omega \right)=\frac{K\sqrt{\mathrm{one}+T_{\mathrm{one}}^2{\mathrm{<figure-callout\; id="2"\; label="\omega "\; filenames="00000027.png"\; state="\{\{state\}\}">\omega </figure-callout>}}^2}}{\omega \sqrt{\left(\mathrm{one}+{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2{\omega }^2\right)\left(\mathrm{one}+{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2{\omega }^2\right)\left(\mathrm{one}+T_{\mathrm{four}}^2{\omega }^2\right)}},\text{(2)}$$

(T₃>T₄); $$K=\frac{K_y}{K_{\omega }{i}_p};$$

R, L - соответственно, активное сопротивление и индуктивность якорной цепи электродвигателя; K_M, K_ω - соответственно, коэффициенты крутящего момента и противоЭДС; K_y - коэффициент усиления усилителя 3; J - суммарный момент инерции, приведенный к валу электродвигателя; i_p - передаточное отношение редуктора.Where $${\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_{3,\mathrm{four}}=\frac{RJ}{2K_M{K}_{\omega }}\pm \sqrt{\frac{R^2{\mathrm{<figure-callout\; id="2"\; label="J"\; filenames="00000027.png"\; state="\{\{state\}\}">J</figure-callout>}}^2}{\mathrm{four}{K}_M^2{K}_{\omega }^2}-\frac{LJ}{K_M{K}_{\omega }}}$$

(T ₃ > T ₄ ); $$K=\frac{K_y}{K_{\omega }{i}_p};$$

R, L - respectively, the resistance and inductance of the armature circuit of the electric motor; K _M , K _ω - respectively, the coefficients of torque and counter-EMF; K _y is the gain of the amplifier 3; J is the total moment of inertia reduced to the motor shaft; i _p - gear ratio.

It is known (see Popov EP Theory of linear systems of automatic regulation and control. M .: Nauka, 1978. - 256 pp.) That with harmonic control of an electric drive with a working amplitude A _p , frequency ω _p and dynamic error not exceeding quantities ε ₁ , the inequality

$$A\left({\omega }_p\right)\ge \frac{A_p}{{\epsilon }_{\mathrm{one}}},\text{(3)}$$

as a result, taking into account expressions (2) and (3), we can write the equality

$$\frac{A_p}{{\epsilon }_{\mathrm{one}}}=\frac{K\sqrt{\mathrm{one}+T_{\mathrm{one}}^2{\mathrm{<figure-callout\; id="2"\; label="\omega \; p"\; filenames="00000027.png"\; state="\{\{state\}\}">\omega \; </figure-callout>}}_p^{}}}{{\omega }_p\sqrt{\left(\mathrm{one}+{\mathrm{<figure-callout\; id="2"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_2^2{\omega }_p^2\right)\left(\mathrm{one}+{\mathrm{<figure-callout\; id="3"\; label="T"\; filenames="00000027.png"\; state="\{\{state\}\}">T</figure-callout>}}_3^2{\omega }_p^2\right)\left(\mathrm{one}+T_{\mathrm{four}}^2{\omega }_p^2\right)}}.\text{(four)}$$

However, taking L into account, it is very difficult to obtain an analytical expression describing the dependence ω _p = f (A _p , ε ₁ ) (see expression (4)). Therefore, at first it is advisable to linearly approximate the current frequency response, and then using the obtained linear dependence from the known ordinate A _p / ε ₁ already find the frequency ω _p .

(см. абсциссу точки G на фиг.2), большая искомой частоты $${\omega }_p^0$$

(см. абсциссу точки F). Но использование $${\omega }_p^{*}$$

> $${\omega }_p^0$$

при формировании входного сигнала неизбежно приведет к тому, что динамическая точность системы ухудшится, превысив ε₁. Для устранения указанной негативной ситуации при поиске текущего значения частоты ω_р в предлагаемом устройстве используется касательная 3 к АЧХ в точке С, которая имеет абсциссу $${\omega }_p^{*}$$

. Используя уравнение этой касательной A_p/ε₁-A( $${\omega }_p^{*}$$

)=A'( $${\omega }_p^{*}$$

)(ω_p- $${\omega }_p^{*}$$

), где A'( $${\omega }_p^{*}$$

) производная А(ω) в точке ω= $${\omega }_p^{*}$$

, можно определить абсциссу ω_р точки Н, имеющей ординату α_p/ε₁. Эта абсцисса в предлагаемом устройстве формируется на входе блока 26 (см. выражение 1) и является искомой частотой задающего гармонического сигнала.From figure 2 it is seen that the approximation of the plot of the incident frequency response in the operating frequency range [ω _min , ω _max ] secant 2, located between the points with ordinates A (ω _min ) and A (ω _max ), will lead to the fact that when using this interval for the known ordinate A _p / ε ₁ will be found frequency $${\omega }_p^{*}$$

(see the abscissa of the point G in figure 2), a large desired frequency $${\omega }_p^0$$

(see abscissa of point F). But use $${\omega }_p^{*}$$

> $${\omega }_p^0$$

in the formation of the input signal will inevitably lead to the fact that the dynamic accuracy of the system will deteriorate, exceeding ε ₁ . To eliminate this negative situation, when searching for the current value of the frequency ω _r , the proposed device uses a tangent 3 to the frequency response at point C, which has an abscissa $${\omega }_p^{*}$$

. Using the equation of this tangent A _p / ε ₁ -A ( $${\omega }_p^{*}$$

) = A '( $${\omega }_p^{*}$$

) (ω _p - $${\omega }_p^{*}$$

), where A '( $${\omega }_p^{*}$$

) the derivative A (ω) at the point ω = $${\omega }_p^{*}$$

, it is possible to determine the abscissa ω _{p of the} point H having the ordinate α _p / ε ₁ . This abscissa in the proposed device is formed at the input of block 26 (see expression 1) and is the desired frequency of the master harmonic signal.

(см. фиг.2), но при этом всегда будет выполняться главное неравенство ε≤ε₁, для обеспечения которого и создавалось предлагаемое устройство. При этом ω_р всегда будут незначительно меньше $${\omega }_p^0$$

.Obviously, the indicated choice of ω _p leads to a slight decrease in the system speed, since ω _p < $${\omega }_p^0$$

(see figure 2), but the main inequality ε≤ε ₁ will always be fulfilled, for which the proposed device was created. Moreover, ω _p will always be slightly less $${\omega }_p^0$$

.

Claims (1)

A self-adjusting electric drive containing a first adder connected in series, a device for correcting an error value of an electric drive, an amplifier, an electric motor with a gearbox, on the output shaft of which a position sensor is installed, the output of which is connected to the first input of the first adder, a quadrator connected in series, the first division unit, the second input of which connected to the output of the first constant signal source, and the second adder, series-connected integrator, sine functional pre the educator and the first multiplication unit, the second input of which is connected to the output of the amplitude setter, and the output to the second input of the first adder, the second constant signal source and the third adder connected in series, the second multiplication unit connected in series, the first input of which is connected to the quad output and the first inputs the fourth, fifth and sixth adders, the third multiplication unit, the second division unit, the square root extraction unit, the seventh adder, the second input of which is connected to the output of the amplitude setter to the second input of the third adder, the fourth multiplication unit and the eighth adder, the second input of which is connected to the output of the third adder and the input of the quadrator, and the output to the integrator input, the fifth multiplication unit is connected in series, the first input of which is connected to the output of the second adder, and the third the division unit, the second input of which is connected to the output of the first constant signal source, to the second inputs of the fourth, fifth and sixth adders and to the first inputs of the fourth, fifth and sixth division units, and the output to the second at the input of the fourth multiplication block, the second inputs of the fourth and fifth division blocks connected, respectively, to the outputs of the fifth and sixth adders, the second input of the sixth division block connected to the output of the fourth adder and the second input of the second division block, and its output to the second input of the second the adder, the third and fourth inputs of which are connected, respectively, to the outputs of the fourth and fifth blocks of division, characterized in that it further introduced sequentially connected ninth adder, the first input of which of the second is connected to the output of the quadrator, and the seventh division unit, the second input of which is connected to the output of the first constant signal source and the second input of the ninth adder, and the output to the fifth input of the second adder, as well as the sixth multiplication unit, the first and second inputs of which are connected, respectively , to the outputs of the fifth and ninth adders, and the output to the second input of the third multiplication unit, and the seventh multiplication unit, the first input of which is connected to the output of the square root extraction unit, the second input to the output of the third adder, and Exit - to the second input of the fifth multiplier.

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