RU1786467C - Automatic regulator - Google Patents

Abstract

An automatic controller can be used to control the temperature and improves the dynamic characteristics of the control process by including a sensor and an adjustable parameter setter of the comparison unit, a driver of the control signal in the form of analog-to-frequency converters and a frequency-phase discriminator. The inputs of the analog-frequency converters and the frequency-phase discriminator are connected to the output of the comparison unit, and their outputs are connected to the inputs of the frequency-phase discriminator, the output of which is connected to the actuator. 3 ill.

Description

The invention relates to automatic control of parameters of objects in automated control systems of industrial plants and can be used, for example, to control temperature, pressure, flow, speed and other parameters, the current values of which can be represented as an analog electrical signal.

Known pulse-width temperature controller for objects with delay, comprising a conversion unit and a communication and disturbance unit, the inputs of which are connected to the inputs of the controller, a comparison unit, the output of which is connected through an amplifier, pulse-width modulator and adder to the object of regulation, and the inputs are connected to the input of the conversion unit directly and the object of regulation through the temperature sensor.

A disadvantage of the analogue is reduced dynamic characteristics.

The closest in technical essence to the claimed invention analogue, selected as a prototype, is an automatic control device comprising a sensor and a variable parameter adjuster connected to a comparison unit, a differentiation unit connected to an input with an adjustable parameter sensor and connected to an output together with the output of the comparison unit to the driver of the control signal, a pulse generator with a frequency-determining circuit, and an actuator.

The disadvantage of the prototype are low dynamic characteristics, because control signal driver made in the form of an adder, generates a control signal as the algebraic sum of signals proportional to the current value of the parameter and the differential component of the feedback signal (sensor signal), and the ratio of

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to ensure the required quality of control depends on the dynamic characteristics of a particular control object, in addition, in the case of programmed measurement of an adjustable parameter, for example, at a constant rate of change of reference and the algebraic sum of the sensor and master signals equal to zero, the differential component of the feedback signal is not is equal to zero and is aimed at changing the control action in the direction of decreasing the rate of change of the adjustable parameter, which brings the control process to overshoot.

An object of the invention is to improve the dynamic performance of a control process.

This goal is achieved in that in an automatic controller containing a sensor and an adjustable parameter setter connected by outputs to the corresponding inputs of the comparison unit, a control signal shaper, and an actuator, the output of which is the output of an automatic controller, the control signal shaper contains two analog-to-frequency converters and a frequency-phase discriminator, the inputs of the analog-to-frequency converters connected to the output of the comparison unit, their outputs connected to Resp input frequency-phase discriminator whose output is coupled to an input of the executive authority.

 When comparing with the prototype and analogue, distinctive features were revealed: the control signal generator contains two analog-to-frequency converters and a frequency-phase discriminator, which allows us to assert that it can be argued that this invention meets the criterion of novelty.

These distinctive features implement a phased program control process, which includes the basic properties of positional and continuous control methods, and provide a new quality of the automatic control process by implementing a control action proportional to the duty cycle of the control signals of the frequency-phase discriminator, the current value of which depends on the difference in the pulse repetition period analog-to-frequency converters of the output signal of the comparison unit, while pulses of analog-frequency converters coincide in the absence of a signal from the comparator when the mismatch signal is zero, on the rate of change of the difference between the pulse repetition periods, on the sign of the time it affects the control system, depending on the dynamic characteristics

control object, automatically taken into account by the functioning algorithm of the invention, which is, therefore, a self-adjusting device.

This property improves the dynamic characteristics of the control process and allows us to conclude that the invention meets the criterion of significant differences.

In FIG. 1 shows a block diagram of an automatic controller; in FIG. 2 is a timing diagram of the operation of the regulator (a, b, c, d, e, e are diagrams of the output voltages of the corresponding blocks); in FIG. 3a, b are analog-frequency conversion plots for analog-to-frequency converters.

The automatic controller comprises a sensor 1, a setter 2, a comparison unit 3, analog-to-frequency converters 4 and 5, a frequency-phase discriminator 6, and

5, the actuator 7, wherein the comparison unit 3 is connected to the sensor 1, the master 2 and the output and inputs of the analog-frequency converters 4 and 5, the outputs of which are connected respectively to the inputs of the frequency-phase discriminator 6, which is connected to the input of the actuator 7.

The device operates as follows.

5 Sensor 1 signal proportional. the current value of the adjustable parameter, and the signal of the setter 2, proportional to the desired value of the adjustable parameter, are converted

0 by comparator 3 to an analog signal proportional to the magnitude and sign of their algebraic sum that arrives; to the inputs of analog-frequency converters 4 and 5.

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The mismatch signal from the output of comparison 3 is converted by analog-to-frequency converters 4 and 5 into two sequences of pulses whose frequencies

0 coincide with a mismatch signal equal to zero and accordingly change when it is present (see Fig. 3).

The frequency-phase discriminator 6 compares two sequences of pulse signals of analog-to-frequency converters along their leading edges and generates an output control signal from executive beam 7 in the form of pulses of varying duration in proportion to the temporal mismatch of the leading edges of the compared signals (see Fig. . 2).

Changing the value of the output signal of control by the executive body is aimed at reducing the current value of the error signal until it disappears completely, which corresponds to the equality of the frequencies of the analog-to-frequency converters with the automatically established value of the time interval between the leading edges of the pulse sequences of the analog-to-frequency converters. The perturbation of the system caused by a change in the value of the signals of the sensor or setter is automatically compensated by a change in the value of the output signal of the frequency-phase discriminator,

An example of an analog-to-frequency converter is the KR1108PP1 microcircuit.

An example of a frequency-phase discriminator is the KR1015XKZ microcircuit,

The use of the inventive controller in automatic control and regulation systems improves the quality of regulation by providing a self-adjusting control mode and minimizing the astatic error.

The controller is intended for use as a unified device for controlling the parameters of industrial plants.

Claims (1)

SUMMARY OF THE INVENTION An automatic controller comprising a sensor and an adjustable parameter setter connected by outputs to respective inputs of a comparison unit, a control signal generator and an actuator, the output of which is an output of an automatic controller, characterized in that, in order to improve the dynamic characteristics of the regulation process , the driver of the control signal contains two analog-to-frequency converters and a frequency-phase discriminator, the inputs of the analog-frequency converters zovateley connected to the output of the comparison unit, their outputs connected to respective inputs of the phase-frequency discriminator with an output connected to the input of the executive authority. 9uz.l rf 8 Z ..lJ.J .. l.Li-UU J L LLJL l l e JllLfL.rLrU UTnJTUnj-irL