SU1444713A1 - Two-channel extremum controller - Google Patents

Abstract

The invention relates to automatic control systems and can be used to control various objects with extreme characteristics, preferably low inertia. The purpose of the invention is to increase the speed of the controller. The controller contains a controlled generator of orthogonal signals 1, two channels of forming a search signal 2, 3, a trigger and 1mitt 4, a differentiator 5, a one-oscillator 6. Improving speed is achieved by independent search using a continuous search signal at which each subsequent cycle is performed. taking into account the coordinates of the extremum found in the previous cycle, 5 Il.

Description

The invention relates to automatic control systems and can be used to control various objects with extreme characteristics, preferably low inertia,

The purpose of the invention is to increase the speed of the controller by using an independent search using a continuous search signal.

Fig. 1 shows a functional diagram of a two-channel extreme regulator; Fig. 2 - electrical circuit of a controllable generator of orthogonal signals; FIGS. 3 - 5 are graphics for explaining the operation of the device.

The regulator () contains a controlled generator of orthogonal signals 1, channels for forming the search signal 2 and 3, Schmitt trigger 4 differentiator 5, one-shot b, first key 7d first scaling resistor 8, capacitive divider 9j second scaling resistor 10, amplifier P, the first repeater 12, the second switch ISj, the capacitor 14, the second repeater J5 and the third mapping resistor J6,

. The controlled oscillator J of orthogonal signals (Fig. 2) contains an input-switched self-oscillator 7 intermittent (self-modulated) oscillations, a zmitter repeater 18 and a phase splitter 19 in the form of two phase-shifted CS chains with a common input, which are gene outputs Ratio 1 (the phase difference of the output signals is (+90) yoga. (- 90, the sign of the role is not played by j auto-bias circuit 20. In the figures, the designations of signals at the generator output () 21 ()) of the movement path 22 - 24 ( FIGS. 4) -5 pulses 25 to 29 (FIG. 5) 5 common bus 30,

The device works as follows.

In the initial state, when the autoregulation system is open, the voltage at the input of the regulator is U., 0. The voltage at the output of the trigger 4 you know the generator I and the keys 7, 13 are off, the voltage on the capacitor 14 and the outputs of the regulator are zero .

g

five

0 5 0

5 about 5

0

When the auto-regulation system is closed, a voltage is applied to the controller input indicating the state of the object of regulation, which is definitely an indicator of the quality of the object Q. (), Where Xj and Xj. - input controllable parameters, by converting the output parameter Y (), one can always obtain Q (X., 5X2) as the voltage of the required polarity. Further, for definiteness, we assume that Q (X, X2) Ug 0 .

When U increases from, О to UBX Е 5 where n is the trigger threshold of 4, the voltage at its output is jumped abruptly, it {reaches to the value rhi mksx, the autogenerator 17 starts and the key 7 opens at the same time, and the signals from the outputs open Oscillator 1 is passed through divider 9, resistor 10 and amplifier 11 on the controller. For the full period, the rate of oscillation is variable and the voltage is 5 and 2 HS. the controller outputs pass twice the extreme values of the opposite signs. The corresponding parameters of the object X ,, Xg and Q Ug, vary from minimum to maximum within a given period of values, t, e. scanning takes place. In each subsequent period, the scanning amplitudes increase exponentially (graph in FIG. 3). The orthogonality of the stresses Uj and Ug allows us to consider the process of extremal search as a certain function on the phase plane – CTPI with Cartesian coordinates and. Zad.dadim her as

F (and,, and) uf -f and. (one)

Equations of orthogonal components in parametric form

(t) cosQt, U2, R (t) (2)

where P (t) P (oD) l-exp (-t / c: Ko) l (3) R (t) R (oo) l-epx (-t / C ,, 7 J beat radio pulses 21 at the leading edge ;

R () | and, makoI. (° o). (ii) x is the maximum values of the amplitudes of the search signals in the steady state generation mode, The difference between the values of P and R is due to the difference in the adjusting characteristics of the actuators of the systems in parameters X and X. Requirement 14

In each case, my P / R ratio is set by selecting the gain of amplifier 11 in the controller channels,

Expressions (1) - (3) form a system of equations of an elliptic developing spiral with a step that kills exponentially. Similarly, a system of equations of a collapsing elliptical helix corresponding to a pulse decay can be made (Fig. 3).

The law of change of the modulating signal does not play a significant role; in particular, the radio pulse envelope can obey the harmonic law. The continuous nature of the functions P (t) and R (t), 4TO, is essential for the implementation of the descriptive search algorithm.

Fig. 4 shows the trajectories (22) of movement along the unfolding helix of point A belonging to the function F (and ,, and). The Hell point on the phase plane corresponds to the extremal state of the object: Q (AQ) U (A) 0. The control accuracy is determined by the region of permissible deviations of the extremum coordinates from the point Hell, which in turn depends on the release thresholds E, and the triggering E of the trigger 4. EJ, E by the magnitude of the hysteresis of the trigger 4. The boundaries of the regions are ellipses 23 and 24, the ratio of the semiaxes of which is P / R.

Scanning of orthogonal stresses according to a harmonic law with an amplitude magnitude ± ± corresponds to the movement of point A from the zero coordinate in a spiral approaching the point Hell. When crossing the border, indicated by an ellipse 23, and trigger 4 is turned off (U, UTU, min b) Due to the inertia of the control process due to the delay of the actuators, the control object itself, the transducer of the output parameter of the object, and the elements of the control moment the extremum is somewhat delayed. Point A, corresponding to the moment the search is stopped, is inside the area bounded by the ellipse 23. The self-oscillator 17 and the key 7 are turned off, and the voltages U "and U. corresponding to AJ are remembered in d 13

Body 9 (more precisely, the values of and are stored, / Kd. and UJ / KOIJ, where KQIJ is the gain of the amplifier 11). Since the output impedance of the key 7 is large, to memorize the voltages on the divider 9, it is necessary that either the discharge circuit is high enough, or there is a charge transfer from another source that is matched with the divider 9 for voltage. The latter has the advantage, as it simultaneously allows each subsequent search cycle, taking into account the coordinates of the extremum found in the previous cycle, which is directly related to an increase in the speed of the controller. This task is solved by a second storage device, performed on elements 12-15.

When trigger 4 is turned off, at time t (A), a one-shot 6 is started with a pulse at the output of differentiator 5, the front of which coincides with the pulse drop of trigger 4 (figure 5 The pulse generated by the one-shot 6 opens the key 13 and the voltage from the output divider 9 through the repeater 12 and the key 13 charges the capacitor 14, the transfer coefficients of the repeater 12 and the Key 13 are close to 1. The charging process of the capacitor 14 is quite short-lived, since the output resistance of the public key is large. Repeater 12 serves to isolate between Lemma 9 and capacitor 14 (due to the high input impedance follower 12 discharge capacitor divider lower arm 9 does not occur). In further voltage divider 9 is maintained by the repeater 15, to the input

the capacitor 14 is connected, the discharge circuit of the capacitor 14 is formed by parallel connection of the output resistance of the open key 13 and the input resistance of the repeater 15, each of which is high, due to which the voltage on the capacitor 14 changes slowly. In FIG. 4, this process corresponds to a segment of a trajectory 22, in FIG. 3, plots 25-29 in the time interval t, -t2 between the pulses of the trigger 4. The slow discharge of the capacitor 14 (plot 27) corresponds to a similar change in the voltage U, U ( Fiq 28) and UBX (chart 29). Feature

five

the latter consists in the fact that its natural gradual approach to the threshold E is accompanied by fluctuation due to a change in the coordinates of the extremum with time due to the effect on the object of regulation of external factors about

During the time interval t, tg between two search cycles, the capacitor (upper arm) of the divider 9 must be discharged through the resistor 8. so that when turning on the key 7, the capacitor of the divider 9 is not abruptly discharged through the relatively low internal resistance of the key 7. At that same time the discharge through the resistor 8: should not be accompanied by a noticeable change in the voltage at the input of the amplifier

From the moment t of the second triggering of the trigger 4, the second search cycle starts when you unlock the key 7., With the transfer coefficient; close to, the value of R g / (R, o-K, b), the total stress is fed to the input of the amplifier 1I and amplified by KQH times to the regulator's output. The second and subsequent search cycles end in a fraction of the period Tj., In the second search cycle, segment A ,, A corresponds to trajectory 22, and on graphs 25-29 in the Sh1 interval of time t.

Resistor 16 serves to prevent the search signal from being bridged by a low-impedance output resistor: repeater 15 Together with resistor 10, it forms a voltage divider j needed to equalize the voltages that come from the amplifier 11 to divider 9 and repeater 15. -Otherwise, when re-recording: voltage recording, from the output of divider 9 to capacitor 14 and transmitting it through repeater 15, a jump in the value of this voltage will occur, since the transfer coefficients of blocks 12,; 13. and 15 are slightly less than one, : Independent of sos However, the object of regulation (more precisely, relay) nature of the search with the help of a continuous signal practically does not impose any limitations on speed, since time-consuming step-by-step processing of information is excluded, as well as auto-generators of harmonic oscillations, as opposed to relaxation (impulse) 5 have significantly

u 15 20

25 30

g 40 45 gQ gg

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wider range of generated frequencies.

Adding the search signal to the voltage stored in divider 9 in the previous cycle reduces the search time to fractions of the period of the generated signal, which further enhances the positive effect of this solution. In this case, the first most prolonged search cycle (Fig. 5) can be considered as an initial transient process, characteristic of almost any, for example, radio-electronic system at the moment of its incorporation.

The independent nature of the search ensures the separation between the input and output signals of the controller, i.e. Fail feedback during search. This is achieved greater than with other control algorithms, stability. system to self excitement.

Claims (1)

Invention Formula A two-channel extreme regulator containing a controlled generator of orthogonal sigy.lov whose first output is connected to the information; The first input channel for forming the search signal, the output of which is connected to the first output of the controller, the second channel for generating the search signal, the output of which is connected to the second output of the controller, is different in that, in order to increase the speed of the controller, a 1-Fmitter trigger is inserted. and one vibrator, - the Schmitt trigger input is connected to the controller input, and the Schgottt trigger output is connected to the first control inputs of the first and second search signal generation channels, with a single output differentiator and with the control input of the controlled generator of orthogonal signals, the second output of which is connected to the information input of the second channel of forming the search signal, the second control. The input of which is connected to the second control input of the first channel for search engine detection and to the one-shot output connected to the output of the differentiator, and each channel to form the search signal contains the first and second switches, the first, second and third scaling resistors, eNncocTHbtf) divider, amplifier, first and second repeaters, separation capacitor, with the control input of the first key connected to the first control input of the search signal generation channel, information input cat This is connected to the information input of the first key connected by the output to the first output of the first scaling resistor and to the input of a capacitive divider, the output of which is connected to the input of the first repeater and through the second A resistor is connected to the amplifier input, the output of which is connected to the output of the channel forming a search signal, the second control input of which is connected to the control input of the second key, whose information input is connected to the output of the first repeater, and the output to the first output of the coupling capacitor and to the input the second repeater, the output of which is connected via the third scaling resistor to the amplifier input, the second terminals of the first scaling resistor and the coupling capacitor are connected to a common bus. 77 W SJ ( EHI o-ChGGNTs I  Zb / Jrf About CPU g Faye. five Ui Faye. I tJLl (m g 28 and.