SU1413598A1 - Extremum controller for resonance object - Google Patents

Abstract

The invention relates to electrical control systems and can be used in frequency control systems for resonant objects of ultrasonic technology and technology, vibration machines, RLC circuits, etc. The aim of the invention is to increase the stability of the controller with periodic changes of the controlled value. The regulator contains a resonant object 1, a controlled-value sensor 2, a rectifier 3, a capacitor 4, elements of comparison 5.9, a pulse arrest detector 6, a discharge key 7, a T-flip-flop 8, an integrator 10, an actuator 11, the Regulator operable and stable with periodic changes of the adjustable value due to the pulse disappearance detector, implemented on the basis of a timer, which eliminates false reverses when searching for a global extremum. 2 Il. (L with

Description

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FIG. one

The invention relates to electrical control systems and can be used in systems for adjusting the frequency of resonant objects, vibration mapping, RLC circuits, etc.

The aim of the invention is to increase the stability of the regulator and with periodic changes of the adjustable value,

FIG. shows a regulator circuit; Fig. 2 shows stress plots showing the operation of an extremal controller.

The regulator contains a resonant object 1, a sensor of a controlled variable 2, a rectifier (diode) 3, a storage capacitor A, the second element of comparison 5, a detector of loss of pulses 6, a discharge key 7, T - trigger 8, the first element of comparison 9 , integrator 10, actuator 11.

The voltage plots depict:

, - voltage ripple power source; U is the output voltage of the controlled-value sensor 2; U is the voltage at the output of the capacitor 3, Uj is the voltage at the output of the capacitor 4; U4 is the voltage at the output of the second element of comparison 5; Uy is the voltage at the output of the pulse-loss detector 6; Ug is the voltage at the first output of the T-flip-flop 8; U is the output voltage, the first element of comparison 9; Ug is the voltage at the output of the integrator 10.

The extreme regulator for the resonant object works as follows. .

Let the modulation of the amplitude of the signal and, - from the output of the sensor 2 of the controlled cycle, be due to the voltage ripples and., &Apos;, the power source (see

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2).

The input of the resonant object 1 from the actuator 1 receives a regulating action, leading to oscillations of the controlled values of the object.

Let, for example, the system be in the preresonance region and a gradual increase in the frequency of the regulating effect occurs. The signal U, proportional to the amplitude of oscillations of a resonant object, from sensor 2 of a controlled value is fed to a series-connected rectifier 3, at the output of which a signal is observed

and (see figure 2). On the capacitor 4, the signal level is memorized by Uj from the output of the upper section 3 ,. and at the output of the capacitor 4 a signal Uj is observed.

The second comparison element 5 compares the signals arriving at its inputs. If the current signal from the output of sensor 2 is larger than the previous one in amplitude, i.e. the capacitor 4 starts to blow, then the output of the second element of comparison 5 is observed to have a pulse U corresponding to 1, which is fed to the input of the loss detector b, which is used to eliminate false adjustments to local extremes that take place in time intervals from t to t ,, from t, to t, j, from tj to t and are caused by the ripple of the supply voltage U.

A detector of impedances 6 outputs a voltage pulse at the output.

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if the pulses V from the output of the second element of comparison 5 are absent during the delay time Tj longer than the time interval between local extremes, which is caused by the frequency

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Neither the first local extremum in the time interval from t to t pulses U4 from the output of the second element of comparison 5 are missing. The pulse disappearance detector 6 is tuned for a longer time interval and therefore there is no signal from its output. At time t, a new subcharge of the capacitor occurs, when the amplitude of the signal u begins to grow again. A pulse U from the output of the second element of comparison 5 is detected by a pulse 6 detector, a pulse Uj is absent at its output, and the process of increasing the oscillation frequency continues until the resonance frequency is reached. When the system reaches the resonant frequency (point A in Fig. 26), the value of the global extremum, on the capacitor 4, is memorized. Then the current value of the signal Uj. With sensor 2 of the controlled variable will be less than the signal from the capacitor 4. Therefore, there are no pulses from the output of the second element of comparison 5; The absence of pulses is 1/4 for a time longer than the period of pulsation and “„ indicates that the system goes beyond the resonant frequency.

Lack of impulses U4. from the output of the second element of comparison 5 is detected by a pulse-detecting detector 6, at its output a level 1 Uj is set, the leading edge of this signal T is the trigger 8 inverts its state. At the same time, the signal Uj is fed to the input of the discharge key 7, which discharges capacitor 4, preparing it for a new operating cycle. With the arrival of the first positive half-wave U, of the capacitor 4, the second element of comparison 5 is triggered, which gives a pulse U4 to the input of the impulse detector 6, after which the level O - Uf is set again at the output of the latter. Detector 6 is ready for: a new work cycle.

T-flip switch is triggered. switching the first element of comparison 9, at the output of which the voltage changes its polarity. As a result, the voltage Ug at the output of the integrator 10 decreases linearly, which leads to a decrease in the frequency of the regulating action — a reverse, which is provided by the actuator P. The system again begins to move towards resonance. The processes for moving to resonance with decreasing frequency are similar to those described above.

A self-oscillatory mode arises in which the amplitude of the controlled variable oscillates about its maximum value, the global extremum, which corresponds to maintaining the extremum with some error in yawing in its vicinity,

Thus, the use of the device makes it possible to increase the stability of the frequency setting in installations and eliminate the error caused by changes in the parameters of the oscillatory system during operation or external disturbances, such as power supply ripples.

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Functions of the detector of impulses transmission 6 impulses eT node based on timer a.

The T-flip-flop is executed on the basis of the IK-flip-flop and is controlled by the synchronization input, with the arrival of each pulse from the impulse detector 6 pulses its state. The first element of comparison 9 is an analog comparator.

Claims (1)

Invention Formula An extreme controller for a resonant object containing a T-flip-flop, the direct and inverse outputs of which are connected respectively to the first and second inputs of the first comparison element, the output of which is connected via serially connected integrator, actuator and resonant object connected to the rectifier input, the output of which is connected to the first output of the storage capacitor and to the first output of the discharge key, the second output of which is connected to A memory storage capacitor with a second output of a controlled variable sensor and with a zero potential bus, which is different in that in order to increase the stability of the trr rdr with periodic changes of the control value, a second comparison element and a propa- tion detector are introduced impulses, connected by the output to the synchronization input of the T-flip-flop and to the control input of the dongle, the input of the impulse detector of the impulses f. It is connected to the output of the second reference element, the first and second inputs of which are connected respectively to the first output of the sensor of the controlled variable and to the first output of the storage capacitor. t / num, ° Dorezonmsnar F i kv one Zarezo Amsnaa Losto 2