SU1254434A1 - Adaptive system for stabilizing non-stationary discrete object - Google Patents

Abstract

The invention relates to automatic control systems and can be used to stabilize the output of a nonstationary, mainly linear object, subject to interference. The invention makes it possible to increase the accuracy of the output coordinate of the control object, which is achieved by combining the training modes. control and mitigation. The system contains meters for input and output values, blocks for calculating their current average values, adders, a correction unit, a task block, a control action calculator, and an actuator. Achievement of the set goal, the comparators block is entered into the system, the inputs of which are connected to the outputs of the first block of adders, and the outputs are connected to the first inputs of the block of I elements, the outputs of which are connected to the control inputs of the block of controlled dividers, the first information inputs of which are connected to the outputs of the first adder unit, the adder, the first input of which is connected to the output value meter, the second input - to the output of the current mean value calculation unit ff its output value value, and: It is provided with an information input of a controllable storage device, the control input of which 3 is connected via a comparator to the output of an output value meter, and you -. the stroke is connected to the second informational inputs of the unit of controlled deltas. The outputs of the latter are connected via ti to the first inputs of the second block of summers, the outputs of which are connected to js to the second inputs of the control action calculator and through the memory block to the second inputs of the second block of adders, the output of the threshold device is connected to J the second inputs of the block of elements I. 2 ill.

Description

The invention relates to automatic control systems and can be used to stabilize the output of a non-stationary, preferably linear object subject to interference.

The purpose of the invention is to increase the accuracy of stabilization of the output of a non-stationary linear object.

The introduction of additional blocks and connections eliminates the separation in time of the training and control modes, since there is no model of the object itself, and the coefficients linking the disturbances of the disturbances with the control action required to compensate for them, so that the output value The statistical value does not depend on the deviations of disturbances and is not affected by changes in the parameters of the control object.

H FIG. 1 shows a functional diagram of the proposed device; in fig. 2 explains its principle of operation.

The adaptive stabilization system for the output of a non-stationary linear object consists of the control object 1, at the input of which controlled disturbances (input quantities) x act. , Xg b of noncontrol of the output value, to the first input of the adder 10 and the input of the comparator 11. The output of the block 9 for calculating the current average value of the output

The magnitude 5 is connected to the second input of the adder 10 and the first input of the control correction unit 12, the second input of which is connected to the setpoint 13 of the output value. Adder output

10 10 is connected to the input of a controlled storage device (RAM) 14, which memorizes the deviation of the output parameter from its current average value, the control input 15 of the ultrasound sensor 14 is connected to the output of the comparator 11, and the output is connected to the first inputs of the block 15 of controlled divisors, the second inputs of which are connected to the outputs of the first block 4 of the sum20 mators, and the controlled inputs to the outputs of the block 7 elements I. The output of the comparator 11 is connected through the delay block 16 to the second inputs of the block 7 elements I. The outputs of the block 15 15 equal divisors are connected to

the inputs of the block 17 are large-scale amplifiers with coefficients v-, the outputs of which are connected to the first inputs of the second block 18 adders. Outputs

30 of the second block 18 of adders are connected to the second inputs of the block 6 of the calculation of control actions and through the block 19 of the memory to its second inputs. Memory block 19 is intended

rolling disturbances 1, CN, i ,,. Nl

,, and, at the output of Blo-35 No. "storing the results, the posuk 2 measuring input quantities, the outputs of which are connected to the inputs of the unit 3 for calculating the current average values of the input values, the outputs of which are connected to the first inputs of the first block 4 of adders, the second inputs of which are connected to the outputs of block 2 measuring input quantities. The outputs of the first block 4 of the adders are connected to the inputs of the block 5 of the comparators and the information inputs of the block 6 for calculating the control actions. The comparator unit 5 is adjusted so that the signal is present at any of its output in the event that the signal at the corresponding input exceeds in absolute value the specified deviation value of 40

45

50

18 adders from the second block, until the next value of perturbations arrives (until the next step N). The output of the correction unit 12 is connected to the third input of the calculation unit 6 of control actions, the output of which is connected to the input of the actuator 20, the output of which is connected with the control input of the control object 1.

Since for a given class of objects, the disturbance fluctuations are of a random nature and have a limited range, in the general case the statistical dependence of the output value of the controlled disturbances can be expressed at discrete points in time by the multiple regression equation. For simplicity, consider a one-dimensional object. In this case

Since for this class of perturbation fluctuations are tea-like and have a limited range, in the general case the static dependence of the output level of the controlled perturbations can be expressed in discrete-time by the equation of multiple regression. For simplicity, consider a one-dimensional object. In this case

mutations S; . The outputs of block 5 of the comparators are connected to the first inputs of the block 55

.... about the regression equation has the form ka 7 elements I. The meter 8 output-

Node value is connected to the input of block 9 for calculating the current average sign Lj N a +.

t

,

2544342

output value, to the first input of the adder 10 and the input of the comparator 11. The output of the block 9 for calculating the current average value of the output

The magnitude 5 is connected to the second input of the adder 10 and the first input of the control correction unit 12, the second input of which is connected to the setpoint 13 of the output value. Adder output

10 10 is connected to the input of a controlled storage device (RAM) 14, which memorizes the deviation of the output parameter from its current average value, the control input 15 of the ultrasound sensor 14 is connected to the output of the comparator 11, and the output is connected to the first inputs of the block 15 of controlled divisors, the second inputs of which are connected to the outputs of the first block 4 of the sum20 mators, and the controlled inputs to the outputs of the block 7 elements I. The output of the comparator 11 is connected through the delay block 16 to the second inputs of the block 7 elements I. The outputs of the block 15 15 equal divisors are connected to

the inputs of the block 17 large-scale amplifiers with coefficients v-, the outputs of which are connected to the first inputs of the second block 18 adders. Outputs

30 of the second block 18 of adders are connected to the second inputs of the block 6 of the calculation of control actions and through the block 19 of the memory to its second inputs. Memory block 19 is intended

No. "memorize the results, post

18 adders from the second block, until the next value of perturbations arrives (until the next step N). The output of the correction unit 12 is connected to the third input of the calculation unit 6 of control actions, the output of which is connected to the input of the actuator 20, the output of which is connected with the control input of the control object 1.

Since for a given class of objects, the disturbance fluctuations are of a random nature and have a limited range, in the general case the statistical dependence of the output value of the controlled disturbances can be expressed at discrete points in time by the multiple regression equation. For simplicity, consider a one-dimensional object. In this case

 +.

This dependence is shown in FIG. 2. Due to the influence of interference, which includes uncontrolled disturbances, the relationship between the input and output of the object is statistical and the regression line 1 only on average determines this relationship. FIG. 2 and M {Y are the mathematical expectations of the perturbation and output value, respectively, whose estimates are their average values and (in relative units x 1, y 1). To eliminate the influence of the controlled perturbation on the output value, it is necessary to apply such control so that the regression line takes position 2 or as close as possible to it.

The inclusion of a comparator block, an And block, a second block of adders, a memory block, a block of large-scale amplifiers, a block of controlled dividers, an adder, a comparator, an ultrasound unit, and a delay block into the device ensures the introduction of an operational correction into the transmission coefficients without disabling the control mode, t . provides a combination of control and training.

With small deviations of the disturbance from the mean value, it may turn out that the sign of this deviation contradicts the physical meaning of the dependence of the output of the object on its input due to the influence of uncontrolled disturbances (for example, point A in Fig. 2). Then the sign of the gain correction factor may turn out to be incorrect, which will lead to a delay in adjusting this coefficient. Turning on the comparators block minimizes the probability of a false step by introducing insensitivity zones defined by the values of 8; (for a one-dimensional object, the dead zone is shown in Fig. 2). The size of the dead zone is chosen to be (0.5- t), 7) d; (where b; is the root-mean-square deviation of the i -th disturbance.

The device works as follows.

Upon receipt of controlled disturbances in the control object 1 by the block 2 of the input value meters, disturbances V, N, x, N are measured

..,., according to which management is conducted. The disturbance signals are received in block 3 of the calculation of the current average values of the input values, which is calculated in each step N of their values, for example, using the known recurrent formula for the current average, using the values, k, x N, ...,

xiCHi ((l - «0 oC; x-, N, (1)

where is X; N- - current average; the value calculated in the previous step; X; tNl - measured value of the I-th input at the Nth step;

oij is a weighting factor. The calculated values are fed to the first block 4 of adders, where as 2 measurements of the input quantities, the measured values of the disturbances are received. In the first block of 4 adders, the perturbation deviation values are calculated

Bx; m.

(2)

These values are remembered until the next signals arrive.

The signals come to the control actions calculation block 6, which calculates the necessary control actions at the Nth step in accordance with the expression

p uU N -IlK; N-ilbX-, N, (3)

where - transfer coefficients, calculated at the previous step and received in block 3 from the output of the second block 18 adders.

Since the parameters that affect the optimal value of K; change rather slowly, the one-step shift has little effect on the control accuracy.

Calculated in block 6 by the formula (3), the magnitude of the control action enters the executor S12

device 20 configuring the control object.

Correction of transfer coefficients h K; N is carried out discretely in the following manner.

Simultaneously with the arrival of the signals in the control calculation unit 6 (x effects, they arrive in the control divider unit 15. The output value meter 8 measures the output parameter y. N. The signal ij N goes in the current average value calculation unit 9 and to the first input adder 10, the second input of which

There is a signal from block 9, calculated .15 you y, J respectively.

The signals b, N а, Гм1 у,, bjM tN Jfj, ...., go to the second block 18 of adders, where they are added to the memorized values of the coefficients

TO; N-i3 calculated in the previous step, i.e.

in it by the formula similar to formula (1).

  i.K-i (-ot + «iyij Nl. (4)

The adder 10 calculates the deviation of the output from the current average value

iy N "y N} -ytNl.

25

40

 TO; N is the new value. The signal fcij tNl goes to the OAS 14. 1st transfer coefficient. From the output of the OZU 14 memorized value The second term of the expression (6) is the deviation of the output value of the arrival, correction to the previous value of the coefficient on the second inputs of the block 15 controlled divisors, on the first inputs of which there are already signals

Ax.tNl,.

The same signals are present at the first inputs of the block 5 of the comparators. On the control actions, the second inputs of the comparator unit 5 are given signals S,, 8, ...., 5, defining the deadband.

Each of the comparators of the block 5 of the comparators works as follows.

If the i-th input contains the AX signal; NC, greater in absolute value of S; , then a signal appears at the f-th output, at the first i-th input of the block 7 elements AND. The second i -th input signal comes from the delay block 16 after the time required to measure and memorize the iyLN of the ultrasound unit 14. If there are signals at the two lx inputs of the block 7 of the AND elements, a signal appears at its i -th output arrives at the i-th input of the control unit 15 control- 55 12 control correction, to another l servo dividers and allows division whose input is given by the specifying signal Lu LN on yx; M. The output is the result of the division:

SO

transfer rate, taking into account the change in process characteristics.

The signals from the output of block 4 adders are received in block 6 of the calculation

After the output value is measured at the output of the comparator 11, and therefore at the control input of the ultrasonic device 14, the signal disappears, the memorized value of the output value deviation is reset and preparation for storing the next value is performed. output atjtN deviations. The measured output value also enters block 9 for calculating the current average value of the output value, which ry calculates the current average value of the output value by the formula (4). The value of M is fed to the input block

9o mi

in accordance with the terms

"

If Ax; tN i6, then the resolution signal in the i -th and divider of block 15 will not follow, and at its -th output the signal will be zero (ie, 0).

In block 17 of scale amplifiers, to the input of which signals a, tN, ajw, ... come from block 15, they are multiplied by weighting factors 25

, N-04b-, Nl,

(6)

 TO; N is the new value of the 1st gain. The second term of expression (6) is the correction to the previous value of the coefficient

control actions

transfer rate, taking into account the change in process characteristics.

The signals from the output of block 4 adders are received in block 6 of the calculation

control actions

12 control correction, to the other input of which a driving signal is applied

After the output value is measured at the output of the comparator 11, and therefore at the control input of the ultrasonic device 14, the signal disappears, the memorized value of the output value deviation is reset and preparation for storing the next value is performed. output atjtN deviations. The measured output value also enters block 9 for calculating the current average value of the output value, which ry calculates the current average value of the output value by the formula (4). The value of M is fed to the input block

12 control correction, to the other input of which a driving signal is applied

9o mi

in accordance with the expression S npHfy (N).,; 0, with | (.) 1 S, j i (7)

-UF at -8, j,

where Ojj is 30Hf insensitivity, in correction block 12, control correction is calculated and fed to block 6 for calculating the control actions, where it is recorded and with the arrival of the next input signals is summed up with a control action that compensates for the effect of disturbances determined by the formula ( 7). Thus, the total control action

  bU: NltuUjN-0.

(eight)

The introduction of a dUX correction eliminates the effect of slow destabilizing factors unrelated to the action of controlled disturbances.

The fixed control action uUm (7) is selected based on the sensitivity of the actuator. The dead zone is selected based on the tolerance for the output parameter of the object.

On this Nth loop setting is for-. is finished and the device is ready for a new cycle (cycle). With the beginning of the (N + 1) -th cycle iUntf l calculated by the formula (7) is summed up with + J and so on.

 Thus, in the proposed system, the training and control modes are combined, it has high noise immunity due to the inclusion of comparators in the circuit 5. This also makes it possible to significantly increase the speed of setting the transmission factors K; N, since the weights are Y; can be quite large, on the order of 0.3-0.5, whereas in a known system for the detuning they should be equal to 0.10-0.12. All this allows with high accuracy to stabilize the output of a nonstationary linear object under the conditions of interference.

Claims (1)

Invention Formula An adaptive stabilization system for a non-stationary discrete object containing an input measurement unit five , Yu 15 20 35 25 jq l 40 50 55 quantities whose outputs are directly connected to the first inputs of the first block of adders and through the block calculating the current average values of the input variables to the second inputs of the first block of adders, the outputs of which are connected to the information inputs of the block calculating control actions whose output is connected to the input of the executive device , the output value meter, the output of which is connected to the first input of the control correction unit through the calculator of the current value of the output value, the second input cat The output is connected to the output of the output value setting block, and the output is connected to the input of the control action calculating block, which, in order to increase the accuracy of the system, a comparators block, an And block of elements, a second block of adders, a memory block, are entered into it ti, block of large-scale amplifiers, controlled divider unit, -summator, comparator, delay unit, controlled storage device, with the inputs of the comparators unit connected to the outputs of the first summator unit, and the outputs connected to the first inputs of the And, o Which odes are connected to the control inputs of the controllable divider unit, the first information inputs of which are connected to the outputs of the first block of adders, the first input of the adder is connected to the output value meter, the second input to the output of the unit calculating the current average value of the output value, and the output is connected to the information the input of the controlled breaking device, the controlled input of which is connected to the output of the comparator, the input of which is connected to the output of the output value meter, and the output of the controlled output the remembering device is connected to the second information inputs of the controllable divider unit, the outputs of which are connected to the first inputs of the second block of adders, the outputs of which are connected to the second inputs of the control actions calculator, and through the memory block to the second inputs of the second block of adders the input of the delay unit is connected to the output of the comparator, and the output is connected to the second inputs of the block of elements I. s ro: Editor L. Pchelinska Compiled by V. Peshkov Tehred M. Khodanych Order 4718/50 Circulation 836 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab, 4/5 Production and printing company, Uzhgorod, Projecto st., 4 FIG. 2 Corrector S.Cherni