RU2592036C1 - Self-tuning electric drive - Google Patents

Abstract

FIELD: electrical appliances.

SUBSTANCE: invention relates to electric drive self-tuning control system. Self-tuning electric drive has series-connected first adder, correction device, amplifier, motor connected directly with speed sensor and via reduction gear with position sensor. Position transducer output is connected to first input of first adder. Adder second input is connected to device input. Second adder, first integrator, third adder and second integrator are connected in series. At that, first input of second adder is connected to output of speed sensor. Second input of third adder is connected to output of position sensor, and output is to second input of second adder and input of second integrator. Output of second integrator is connected to third input of first adder.

EFFECT: technical result consists in provision of serviceability of electric drive at defects of position sensor.

1 cl, 1 dwg

Description

The invention relates to the field of automatic control of electric drives when defects occur in their position sensors.

A self-adjusting electric drive is known comprising a mismatch meter, a regulator, an amplifier, an electric motor with a gearbox, the output shaft of which is connected to a speed sensor and a position sensor, the output of which is connected to the first input of the mismatch meter, the second input of which is connected to the input of the mismatch, the first relay is connected in series element, the first adder, the second input of which is connected to the output of the speed sensor and the input of the first relay element, and its third the first input with the output of the current sensor of the armature winding of the electric motor, the first integrator, the first rectifier, the division unit, the second input of which through the second rectifier is connected to the output of the speed sensor, a sampling-storage element, the second input of which is connected through the second relay element to the output of the speed sensor, and its output with the second input of the controller, the second and third adders connected in series, the second integrator, the fourth adder, the second input of which is connected to the output of the current sensor, the first multiplication unit, the third integrat p and a second multiplication unit, the second input of which is connected to the second input of the controller, and its output to the third input of this controller, connected in series with the third multiplication unit, the first input of which is connected to the output of the second adder, and its second input with the second input of the first multiplication unit and through a functional converter with the output of the second integrator, the fifth adder, the second input of which is connected to the output of the constant voltage source, and the fourth multiplication unit, the second input of which is connected to the output of the fourth Mathator, and its output with the second input of the third adder, the third input of which is connected to the output of the fifth multiplication unit, connected by the first input to the output of the second integrator, and the second input with the output of the third integrator, the first and second inputs of the second adder connected respectively to the outputs of the speed sensor and amplifier (see RF patent No. 2060530, IPC G05B13 / 02, 1996).

The disadvantage of this device is that it allows you to improve the accuracy and quality of the control process, when the inertia of the control object and the resistance of the armature winding of the electric motor change significantly, but accommodation is not provided for defects in the drive position sensor.

A self-adjusting electric drive is also known, containing a first adder connected in series, an inertial differentiating element, a multiplication unit, a second adder, the second input of which is connected through an aperiodic link to the output of the first adder, an amplifier, an electric motor, a gearbox, on the output shaft of which a position sensor is installed, the output of which is connected to the second input of the first adder, the first input of which is connected to the input of the electric drive, as well as a speed sensor mounted on the output shaft of the electrode a needle, series-connected motor current sensor, a third adder and integrator, as well as a division unit, the second input of the third adder through the first relay element is connected to the output of the speed sensor, as well as to the inputs of the first rectifier and the second relay element, the first input of the division unit through the second rectifier connected to the output of the integrator, its second input is connected to the output of the first rectifier, and the output to the first input of the sample-storage element, the second input of which is connected to the output of the second relay element a, and the output is through a functional converter that implements a piecewise-linear approximation of the nonlinear function, the inverse cutoff frequency of the amplitude-frequency characteristic of the electric drive and depending on the changing total reduced moment of inertia of the rotor of the electric motor and the rotating parts of the gearbox with the control object - with the second input of the multiplication unit (see RF patent No. 2397529, IPC G05B13 / 00, 2010).

The specified device in its technical essence is the closest to the proposed invention. But its disadvantage is that it, providing high quality control at any value of its total moment of inertia, does not allow to maintain high dynamic accuracy when errors occur in the operation of the position sensor of the output shaft of the gearbox.

The task to which the claimed technical solution is directed is to ensure the consistently accurate operation of the electric drive when defects occur in the position sensor.

The technical result that can be obtained by implementing the proposed technical solution is expressed in ensuring the insensitivity of the electric drive to emerging defects in the position sensor due to the formation of an additional control action applied to its input. This preserves the operability of the electric drive during its operation.

The problem is solved in that in a self-adjusting electric drive containing a series-connected first adder, a correction device, an amplifier, an electric motor connected with a speed sensor directly and through a gearbox with a position sensor, the output of which is connected to the first input of the first adder, the second input of which is connected to the input of the device, in addition, a second adder is connected in series, the first input of which is connected to the output of the speed sensor, the first integrator, the third an adder, the second input of which is connected to the output of the position sensor, and the output to the second input of the second adder and the input of the second integrator, the output of which is connected to the third input of the first adder.

A comparative analysis of the essential features of the proposed technical solution with the essential features of the analogue and prototype indicates its compliance with the criterion of "novelty."

In this case, the distinguishing features of the claims ensure the invariance of the electric drive to errors in the operation of its position sensor, which ensures consistent quality during its operation.

- угол поворота выходного вала редуктора; $${\alpha }_{\text{н}}^{\text{вх}}$$

- задающий (входной) сигнал, $$\dot{\alpha }$$

- скорость вращения вала электродвигателя, $$\epsilon$$

- ошибка электропривода.The invention is illustrated in the drawing, which shows a structural diagram of a self-adjusting electric drive and the following notation is introduced: $${\alpha }_{\text{n}}^{}$$

- angle of rotation of the output shaft of the gearbox; $${\alpha }_{\text{n}}^{\text{in}}$$

- specifying (input) signal, $$\dot{\alpha }$$

- rotation speed of the motor shaft, $$\epsilon$$

- electric drive error.

The self-adjusting electric drive contains serially connected first adder 1, correction device 2, amplifier 3, electric motor 4, connected directly with speed sensor 5 and through gearbox 6 to position sensor 7, the output of which is connected to the first input of the first adder 1, the second input of which is connected to the input of the device, connected in series to the second adder 8, the first input of which is connected to the output of the speed sensor 5, the first integrator 9, the third adder 10, the second input of which is connected to the output yes snip position 7, and the output - to the second input of the second adder 8 and the input of the second integrator 11 whose output is connected to a third input of the first adder 1, the control object 12.

, обеспечивающее требуемый закон изменения угла $${\alpha }_{\text{н}}^{}$$

. На выходе первого сумматора 1, все положительные входы которого имеют единичные коэффициенты усиления, вырабатывается сигнал $$\epsilon$$

, который после коррекции в корректирующем устройстве 2, усиливаясь, поступает на электродвигатель 4, приводя его вал во вращательное движение с направлением и скоростью (ускорением), зависящим от величины поступающего напряжения. The electric drive operates as follows. A control action is applied to its input. $${\alpha }_{\text{n}}^{\text{in}}$$

providing the required law of angle change $${\alpha }_{\text{n}}^{}$$

. At the output of the first adder 1, all positive inputs of which have unit gains, a signal is generated $$\epsilon$$

which, after correction in the correction device 2, amplifies, enters the electric motor 4, bringing its shaft into rotational motion with direction and speed (acceleration), depending on the magnitude of the incoming voltage.

, снижающую точность работы электропривода в процессе выполнения им конкретных технологических операций. If a defect occurs in the position sensor 7, its output signal will contain an error $$\delta$$

, which reduces the accuracy of the electric drive in the process of performing specific technological operations.

(где $$i_{\text{р}}$$

- передаточное отношение редуктора 8), а его второй положительный вход - коэффициент усиления $$\omega$$

. В результате на выходе этого сумматора формируется сигнал The first positive input of the second adder 8 (from the side of the speed sensor 5) has a gain $$\frac{\mathrm{one}}{i_{\text{R}}}$$

(Where $$i_{\text{R}}$$

- gear ratio 8), and its second positive input is the gain $$\omega$$

. As a result, a signal is generated at the output of this adder

, (1) $${\dot{x}}_{}^{*}=\frac{\dot{\alpha }}{i_{\text{R}}}+\omega r$$

, (one)

, который является некоторой оценкой выходного сигнала датчика положения 7, где and at the output of the first integrator 9 having a unity gain, a signal $$x_{}^{*}={\displaystyle \int (\frac{\dot{\alpha }}{i_{\text{R}}}+\omega r})dt$$

which is some estimate of the output of the position sensor 7, where

(2) $$r={\alpha }_{\text{n}}-x^{*}$$

(2)

- the output signal of the third adder 10 having a first negative (from the side of the first integrator 9) and second positive inputs with unity gain.

, несложно получить: $$\dot{r}=-\omega r,$$

если дефекты в датчике положения 7 отсутствуют. Если же они присутствуют, то имеет место выражение Taking the derivatives of the left and right sides of the expression (2), taking into account the expression (1), as well as the fact that in the absence of defects in the position sensor 7, the expression $${\dot{\alpha }}_n=\dot{\alpha }/i_R$$

, it is easy to obtain: $$\dot{r}=-\omega r,$$

if there are no defects in the position sensor 7. If they are present, then the expression

, (3) $$\dot{r}=-\omega r+\dot{\delta }$$

, (3)

- величина, характеризующая ошибку измерения датчиком положения 7 угла $${\alpha }_{\text{н}}^{}$$

(она является производной от ошибки измерения $$\delta$$

). Where $$\dot{\delta }$$

- a value that characterizes the measurement error of the angle 7 position sensor $${\alpha }_{\text{n}}^{}$$

(it is a derivative of the measurement error $$\delta$$

)

. Поскольку положительная величина ω может быть выбрана достаточно большой, то в быстро наступающем установившемся режиме работы системы (спустя малое время t) имеет место соотношение $$\dot{\delta }=\omega r.$$

В результате на выходе второго интегратора 11, имеющего коэффициент усиления $$\omega$$

, формируется искомый сигнал ошибки измерения $$\delta =\omega {\displaystyle \int \text{[}{\alpha }_{\text{н}}\text{-}{\displaystyle \int (\frac{\dot{\alpha }}{i_{\text{р}}}+\omega r})dt\text{]}dt}$$

, который присутствует в показаниях датчика положения 7. В первом сумматоре 1 происходит вычитание найденного сигнала ошибки $$\delta$$

из выходного сигнала датчика положения 7, в котором присутствует эта ошибка. В результате удается получить точное (искомое) значение угла поворота выходного вала электропривода $${\alpha }_{\text{н}}^{}$$

и тем самым сохранить высокую точность его работы.The solution of equation (3) has the form: $$r(t)=C_{\mathrm{one}}{e}^{-\omega t}+\frac{\dot{\delta }}{\omega }$$

. Since the positive value of ω can be chosen large enough, in the rapidly onset steady-state mode of operation of the system (after a short time t), the relation $$\dot{\delta }=\omega r.$$

As a result, the output of the second integrator 11 having a gain $$\omega$$

, the desired measurement error signal is generated $$\delta =\omega {\displaystyle \int \text{[}{\alpha }_{\text{n}}\text{-}{\displaystyle \int (\frac{\dot{\alpha }}{i_{\text{R}}}+\omega r})dt\text{]}dt}$$

, which is present in the readings of the position sensor 7. In the first adder 1, the found error signal is subtracted $$\delta$$

from the output of the position sensor 7 in which this error is present. As a result, it is possible to obtain the exact (desired) value of the angle of rotation of the output shaft of the electric drive $${\alpha }_{\text{n}}^{}$$

and thereby maintain the high accuracy of its work.

Claims (1)

A self-adjusting electric drive, comprising a first adder, a correction device, an amplifier, an electric motor connected to the speed sensor directly and through a gearbox with a position sensor, the output of which is connected to the first input of the first adder, the second input of which is connected to the input of the device, characterized in that in addition, a second adder is connected in series, the first input of which is connected to the output of the speed sensor, the first integrator, the third adder, W swarm input of which is connected to the output of the position sensor and an output - to a second input of the second adder and the input of the second integrator whose output is connected to a third input of the first adder.

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