SU711545A1 - Device for measuring parameters of control system links - Google Patents

Description

The invention relates to automatic control and can be used in the study and adjustment of automatic control systems. A device for measuring parameters of links of control systems is known, comprising an integrator, the inputs of which are connected to the inputs of the link under investigation, and an output with a measuring device 1. The device for measuring parameters of links of control systems comprising a measuring unit and an integrator are closest to the invention. The input of which is connected with the input of the link under study 2. The disadvantage of these devices is that with their help it is possible to measure the parameters of only one type of links — first order links then As in practice, it is quite often necessary to deal with links whose transfer function has W (p) p (Tp + 1). The purpose of the invention is to expand the functionality of the device. This is achieved by the fact that it has a day and a scaling unit, the input of which is connected to the output of the link under study, the output to the first input of the adder, the second input which is connected to the output of the integrator, and the output to the input of the measuring unit. The drawing shows a functional diagram of the device. It contains linkable link 1, integrator 2, scaling unit 3, adder 4, measuring unit 5. The device operates in response, the signal taken from the input of link 1 is fed to integrator 2, the output of which is connected to the input of adder 4, to another input adder 4 with the opposite sign gives a signal from the output of the scaling unit 3, the input of which is connected to the output of the probed link 1 The measurement process consists of two operations; setting the gain of the scaling unit and actually measuring the parameters of the link. The transmission coefficient is set as follows. At the test link input, a rectangular signal is applied, At steady state, by changing the transfer coefficient of the scaling block, zero reading of the measuring device 5 is obtained. After this operation, the device is calibrated and, after returning it to its original state, you can begin to determine the parameters of the link 1 under investigation. this is necessary, by giving a step signal to the input of the link under study, using measurement unit 5 to perform the determination of parameters at the end of the transition process.

Let's do this mathematical proof.

The studied link is linear, the principle of superposition is applicable to it, i.e. The reaction of the studied link to a rectangular impulse can be considered as the sum of the reactions of the link: positive step action applied at time t and negative step effect of the same amplitude applied at time t + g, where the pulse duration. Then the response of the studied link to a rectangular pulse of duration C can be represented

h (t) at О t iry (t) 1 (1)

h (t) + -h (t-r)} prigr,

where h (t) is the reaction link to the step action, but.

h (t) (1-e), (2) where -V is the amplitude of the rectangular pulse.

Trgda from (1) and (2) .i.

f -T (1st)

y (t) -} - tjr g / t

(Q) g - “- te (1st) f Sett value

y (oQ) -Vkf. (4)

When applying to the input of the examined, a link 1 of a rectangular pulse of duration T, the signal at the first input of the adder 4 is determined as

Z. Jxdt jDdt VT (5)

the signal at the output of the adder 4 Z, - Z,

but

Zj k y (co,

(6)

where K is the static transfer ratio of the scaling unit 3, and, since by changing the transfer coefficient Kj, the value of 2d O is achieved in a steady state,

2g (") - 2 (00) o (7)

From (4), (5), (6) and (7) we have

k - k

(eight)

Let us further carry out a mathematical proof that when 5 is fed to the input of the studied link 1 of a single step action, the measuring unit 5 in the established mode registers the value of the parameter T.

0 As a result of structural transformations, the signal at the input of the measuring unit 5 is recorded in an operator form.

15- -

4 Tr h -1

(9)

The solution of a linear differential equation with constant coefficients (9) is the expression

Z (t) Settled value

2 () T

Thus, the measuring unit 5 in the steady state registers the value of the parameter T.

The proposed device makes it possible to measure the parameters of links

  R()

that fundamentally distinguishes this device from previously known ones.

 the invention

A device for measuring the parameters of the links of the control systems, comprising a measuring unit and an integrator, the input of which is connected to the input

The studied link, characterized in that, in order to expand the functionality of the device, it contains an adder and a scaling unit, the input of which is connected to the output of the studied link, the output is connected to the first input of the adder, the second input is connected to the integrator output, and the output is vdsds 1 measuring unit.

Information sources,

taken into account in the examination

1 USSR author's certificate №467332, cl. H 02 T 3/24, 1971.

2. Bortsov Yu, A., Suvorov T.V. and Shestakov Yu.S. Experimental determination of the parameters of automated electric drives. L., Energie, 1969, p. 16 (prototype) ..

Claims (1)

Claim A device for measuring the parameters of links of control systems, comprising a measuring unit and an integrator, the input of which is connected to the input of the studied link, characterized in that, in order to expand the functionality of the device, it contains an adder and a scaling unit, the input of which is connected to the output of the studied link, the output - to the first input of the adder, the second input of which is connected to the output of the integrator, and the output is connected to the input of the measuring unit.