SU463949A1 - Device for controlling the dynamic characteristics of control systems - Google Patents

Description

one

The invention relates to the field of automatic control and can be used to determine and control the dynamic characteristics of linear automatic control systems for various purposes.

During the operation of some objects, it is required to conduct operational control of their dynamic characteristics, which is performed automatically.

Of the known methods of controlling dynamic characteristics, high efficiency provides control of the frequency of the "zero phase, and analog and digital devices are used to control the frequency of the zero phase, based on measuring the phase shift between zero transitions of the output and input signals of the system under study and searching for the signal frequency whose phase shift is zero.

A disadvantage of the known devices is the insufficiently high speed, since the search for the frequency of the zero phase is carried out by successively searching through a number of frequencies selected according to a certain law. The speed of the device is also limited by transients in the generator circuit when its frequency is tuned. The disadvantage is also the complexity of the circuit implementation, due to the difficulty of automating the frequency tuning process.

Automation of the search for the frequency of the zero phase at higher speeds is provided by a digital automatic control with a generator of sinusoidal oscillations based on a code-analogue converter.

The disadvantages of the digital control machine include the complexity of the circuit implementation and the insufficiently high speed. The speed of such a control automaton is limited by the search for the frequency of the “zero phase” by the method of sequential iteration of the frequency grid.

The complexity of the automaton is due to its construction on the Fourier transform, which is rather difficult to implement.

The advantage of such an automaton is that it can be used for nonlinear systems. But under operating conditions, where high accuracy requirements are not imposed on the control of dynamic parameters, and the requirements for speed and simplicity of the circuit implementation prevail, control systems can be considered quasi-linear and can be used to control simpler devices.

The purpose of the proposed device is to simplify the circuit implementation and increase the efficiency (speed) of the control.

The proposed device, as well as the known, contains the converter code -

analog, pulse shaper and phase character analyzer.

The distinctive features of the proposed device include the introduction of a phase converter in its composition - a code and a converter code - frequency. The phase-to-code converter serves to convert the phase shift between the output and input signals of the object under study into a proportional code.

The phase-to-code converter is connected in bitwise way with the first inputs of a reversible adder, which performs the functions of summation and storage of the frequency code of the zero phase. By the second inputs, the adder is connected bitwise with the block for setting the nominal frequency of the zero phase, and the reverse input with the output of the phase sign analyzer. By its outputs, the adder bit is connected to the converter code - frequency, connected to the converter code - analogue.

The structural scheme of the proposed device is shown in the drawing.

Its main nodes are the zero phase nominal frequency setting 1 unit, the reversing adder 2, the code-frequency converter 3, the code converter is analog 4, the object under study 5, the phase 6 sign analyzer, the pulse driver 7, the phase converter is code 8 and transfer unit 9.

In the initial state, a code corresponding to the nominal value of the zero phase frequency is entered from the nominal value setting unit 1 into the reversible adder 2. At the output of the transducer code - frequency 3, a sequence of pulses appears, the frequency of which corresponds to the code entered in the reversing adder 2. The received pulses go to the transducer code - analog 4, which forms a sinusoidal signal.

This signal is fed to the input of the object under study 5, as well as to the inputs of the phase 6 sign analyzer and the pulse shaper 7. The output signal of the object under study is also fed to the pulse shaper. The shaper selects the moments of the transition of sinusoidal signals through zero in the upstream region and generates short pulses at these moments. These pulses are fed to the input of a phase converter - code 8, which converts the phase shift into a proportional binary code.

The phase 6 character analyzer determines the phase mismatch sign and controls the mode of operation of the adder 2 in accordance with this sign.

The transfer unit 9 carries out code transfer from the phase converter - code 8 to the reversible adder 2.

Depending on the mode of operation of the adder, set by the analyzer sign phase

6, the code is summed or subtracted with the code of the nominal zero phase frequency. In line with this, the frequency at the output of the converter code - frequency 3 increases and decreases, and consequently, the frequency of the stimulating signal at the output of the converter code - analogue 4.

Since, in the frequency domain of the zero phase, the phase-frequency characteristic of the object under study 5 is, as a rule, linear, and the input-output characteristics of the phase converter — code 8 and code-frequency 3 are also linear, the frequency search of the zero phase is performed in almost 2-3 period of the stimulating signal, i.e. significantly

faster than known devices.

Subject invention

A device for monitoring the dynamic characteristics of control systems, comprising a code converter, an analogue connected by its outputs to a phase sign analyzer and pulse shaper, characterized in that it contains a phase-code converter, a transfer unit, and a reversible adder in order to improve device performance. The code-frequency converter, the transfer unit is bitwise connected to the first inputs of the reversible adder, and the block for setting the nominal frequency value to zero. phase, bitwise connected by its outputs to the second inputs of the reversible adder, the reverse input of which is connected to the phase sign analyzer.

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