CN102707142A - Frequency spectrum analyzing method and device of control object - Google Patents

Abstract

The invention provides a frequency spectrum analyzing method of a control object, comprising the following steps: presetting the resistance of an inductance-capacitance-resistance (LCR) oscillating circuit, wherein the value of the resistance is more than -2 and less than 0; obtaining the input signal of the system control object, and obtaining the output signal of the system control object; inputting the input signal to the LCR oscillating circuit, obtaining the first response signal after performing the convergence treatment; inputting the output signal to the LCR oscillating circuit, obtaining the second response signal after performing the convergence treatment; comparing the first response signal with the second response signal to obtain the spectrum analysis result of the system control object. The invention further puts forward a spectrum analysis device of the control object. The anti-interference ability of the system is improved, and the reliability of the frequency spectrum analysis is improved.

Description

The frequency spectrum analysis method of controlling object and device

Technical field

The present invention relates to field of industrial automatic control, particularly relate to the frequency spectrum analysis method and the device of controlling object.

Background technology

The frequency characteristic of system's controlling object is the fundamental basis of Control System Design and parameter adjustment.The Points Identification for Process Frequency Response ultimate principle is: system's controlling object is under the pumping signal effect; Obtain system or object input signal and the frequency spectrum characteristic of output signal respectively through the frequency spectrum discrimination method, mainly comprise: amplitude-frequency spectral property, phase spectral characteristic etc. at frequency domain.

But the process signal of industrial process systems generally receives the interference of various inside and outside random noises, and noise has constituted very important influence to the Points Identification for Process Frequency Response of Process Control System.

See from system response identification angle; Most process object has the characteristic of similar low-pass filter; Pumping signal is through behind the object; Relative high frequency rate signal outside the object low-pass cut-off frequencies will have decay by a relatively large margin; Particularly exist under the noise of higher-strength at system's controlling object output terminal, the jamtosignal characteristic of these relative high frequency rate signals will worsen significantly, and the Points Identification for Process Frequency Response quality of system's controlling object on these relative high frequency rates normally is difficult to guarantee.

Summary of the invention

The objective of the invention is to propose the frequency spectrum analysis method of controlling object, improve the antijamming capability of system, improve the reliability of spectrum analysis.

For achieving the above object, the technical scheme of employing is:

The frequency spectrum analysis method of controlling object comprises step:

The resistance of preset LCR oscillatory circuit;

Obtain the input signal of system's controlling object;

Obtain the output signal of system's controlling object;

Said input signal is imported said LCR oscillatory circuit, and carry out obtaining first response signal after the convergence process;

Said output signal is imported said LCR oscillatory circuit, and carry out obtaining second response signal after the convergence process;

More said first response signal and said second response signal obtain the spectrum analysis result of said system controlling object.

The inventive method at first is provided with the resistance of LCR oscillator, and the signal amplitude of process LCR oscillatory circuit is index in time to be strengthened, and the influence of noise also just weakens gradually like this, thereby has reduced the jamtosignal of output frequency signal significantly; With the signal of LCR oscillatory circuit output, multiply by a convergence exponent function that is complementary then, finally obtain being still the signal of constant amplitude output; But the jamtosignal characteristic of signal is significantly improved, thereby under stronger noise environment, has significantly improved controlling object frequency domain characteristic identification quality, has improved the antijamming capability of system, improves the reliability of spectrum analysis.

The present invention also aims to propose the frequency spectrum analysis method of controlling object, improve the antijamming capability of system, improve the reliability of spectrum analysis.

For achieving the above object, the technical scheme of employing is:

The arrangements for analyzing frequency of controlling object comprises:

Pre-configured unit is used for the resistance of preset LCR oscillatory circuit;

First acquiring unit is used to obtain the input signal of system's controlling object;

Second acquisition unit is used to obtain the output signal of system's controlling object;

First signal processing unit is used for said input signal is imported said LCR oscillatory circuit, and carries out obtaining first response signal after the convergence process;

The secondary signal processing unit is used for said output signal is imported said LCR oscillatory circuit, and carries out obtaining second response signal after the convergence process;

Spectral analysis unit is used for more said first response signal and said second response signal, obtains the spectrum analysis result of said system controlling object.

Apparatus of the present invention at first are provided with the resistance of LCR oscillator, and the signal amplitude of process LCR oscillatory circuit is index in time to be strengthened, and the influence of noise also just weakens gradually like this, thereby has reduced the jamtosignal of output frequency signal significantly; With the signal of LCR oscillatory circuit output, multiply by a convergence exponent function that is complementary then, finally obtain being still the signal of constant amplitude output; But the jamtosignal characteristic of signal is significantly improved, thereby under stronger noise environment, has significantly improved controlling object frequency domain characteristic identification quality, has improved the antijamming capability of system, improves the reliability of spectrum analysis.

Description of drawings

Fig. 1 is an embodiment process flow diagram of the inventive method;

Fig. 2 is an embodiment synoptic diagram of the inventive method;

Fig. 3 is a structural representation of apparatus of the present invention.

Embodiment

For ease of understanding, will combine accompanying drawing to set forth below.

The present invention proposes the frequency spectrum analysis method of controlling object, please refer to Fig. 1, comprises step:

The resistance of S101, preset LCR oscillatory circuit;

S102, obtain the input signal of system's controlling object, and the output signal that obtains system's controlling object;

S103, input signal is imported the LCR oscillatory circuit, and carry out obtaining first response signal after the convergence process;

S104, will export signal input LCR oscillatory circuit, and carry out obtaining second response signal after the convergence process;

S105, comparison first response signal and second response signal obtain the spectrum analysis result of system's controlling object.

The inventive method at first is provided with the resistance of LCR oscillator, and behind the signal process LCR oscillatory circuit, amplitude is index in time and strengthens, and the influence of noise also just weakens gradually like this, thereby has reduced the jamtosignal of output frequency signal significantly; With the signal of LCR oscillatory circuit output, multiply by a convergence exponent function that is complementary then, finally obtain being still the signal of constant amplitude output; But the jamtosignal characteristic of signal is significantly improved, thereby under stronger noise environment, has significantly improved controlling object frequency domain characteristic identification quality, has improved the antijamming capability of system, improves the reliability of spectrum analysis.

Fig. 2 is one embodiment of the present of invention synoptic diagram, the be interfered influence of signal of the output signal of system's controlling object; The signal that obtains the input system controls object is to the LCR oscillatory circuit, and the output signal that obtains system's controlling object is to the LCR oscillatory circuit; Behind the LCR oscillatory circuit, handle through multiplier again, carry out frequency spectrum processing then, the output spectrum result.

Wherein, the LCR pierce circuit is made up of inductance L, capacitor C, resistance R, when the resistance R end is exported, can use following transport function statement relation between the two at frequency signal:

$G_f\left(s\right)=\frac{Y\left(s\right)}{X\left(s\right)}=\frac{{\mathrm{RT}}_{I}S}{T_I{T}_D{s}^2+{\mathrm{RT}}_{I}s+1}---\left(1\right)$

In the formula (1), R representes resistance; T _IThe pairing integration constant of expression electric capacity; T _DThe pairing derivative constant of expression inductance; S representes plural cps.

Be without loss of generality, make T _I=T _D=T _O, then formula (1) converts formula (2) into:

$G_f\left(s\right)=\frac{Y\left(s\right)}{X\left(s\right)}=\frac{{\mathrm{RT}}_{O}s}{{T_O}^2+s^2+{\mathrm{RT}}_{O}s+1}---\left(2\right)$

Wherein, LCR oscillator centre frequency ω ₀For:

${\mathrm{\ω}}_o=\frac{1}{\sqrt{T_I{T}_D}}=\frac{1}{T_O}---\left(3\right)$

Formula (2) unit-step response is formula (4):

$Y_f\left(s\right)=\frac{{\mathrm{RT}}_{O}s}{s({T_O}^2{s}^2+{\mathrm{RT}}_{O}s+1)}---\left(4\right)$

Formula (4) is carried out the Laplace inverse transformation obtains formula (5):

$Y_f\left(t\right)=\frac{R}{\sqrt{1-R^2/4}}{e}^{-0.5R{\mathrm{\ω}}_{O}t}\sin \left({\mathrm{\ω}}_{O}t\sqrt{1-R^2/4}\right)---\left(5\right)$

If in the formula (5);-2 < R < 0; Then the amplitude of formula (5) sine wave output signal is index

and disperses, and abbreviates the LCR diverging oscillation as.

If but formula (5) multiply by a convergence exponent function

then obtain formula (6):

$Y_F\left(t\right)=e^{0.5R{\mathrm{\&omega;}}_{O}t}{Y}_f\left(t\right)=\frac{R}{\sqrt{1-R^2/4}}\sin \left({\mathrm{\&omega;}}_{O}t\sqrt{1-R^2/4}\right)---\left(6\right)$

Formula (6) sine wave output signal remains constant amplitude, simply is called LCR and disperses the convergence vibration.

For the simplification problem, when the R span hour, like | R|＜0.2, then formula (6) can be approximated to be formula (7), compares its former formula, its amplitude is about with the error of frequency generation ± 0.5%, on engineering, can accept fully.

Y _F(t)≈Rsin(ω _Ot) (7)

Formula (7) shows that under step excitation, LCR disperses the convergence vibration and is output as centre frequency ω ₀The constant amplitude sinusoid signal.

But in fact have a problem, along with the increase of time, it is infinitely great that the amplitude of formula (5) sine wave output signal will be tending towards, and may cause physical equipment to calculate and make mistakes, and mainly is transfiniting of numerical range.Therefore on calculating, limit.

Therein in embodiment, before above-mentioned S102 step, the preset time (for example :) of obtaining input signal with the output signal of system's controlling object at 10 cycle sine wave signals of output; When Preset Time arrives, then stop the current frequency spectrum analysis.

Arrangement formula (2) obtains LCR oscillator closed loop form, is formula (8):

$G_f\left(s\right)=\frac{Y\left(s\right)}{X\left(s\right)}=\frac{R{T}_{o}s}{{T_o}^2{s}^2+{\mathrm{RT}}_{o}s+1}=\frac{R/(T_{o}s+R)}{1+[R/(T_{o}s+R)]*[1/\left({\mathrm{RT}}_{o}s\right)]}---\left(8\right)$

Actual necessary through the closed loop form, promptly formula (8) realizes the LCR oscillator function.

To sum up, the present invention can be used to obtain the data source of frequency-domain analysis, and preferably, this data source is the sine wave signal or the sine-wave response signal of present count frequency.

In embodiment, above-mentioned S103 step is specially therein:

Input signal is imported the LCR oscillatory circuit, obtain first and disperse signal;

Disperse signal times with convergent function with first, obtain first response signal;

Above-mentioned S104 step is specially:

To export signal input LCR oscillatory circuit, and obtain second and disperse signal;

Disperse signal times with convergent function with second, obtain second response signal;

Wherein, convergent function is:

ω ₀Be the centre frequency of said LCR oscillator, R is the resistance identical with the resistance of presetting the LCR oscillatory circuit, and t is the time.

In embodiment, above-mentioned 105 steps comprise therein:

Obtain the amplitude information and the phase information of first response signal;

Obtain the amplitude information and the phase information of second response signal;

Compare the amplitude information of first response signal and the amplitude information of second response signal; And, compare the phase information of first response signal and the phase information of second response signal;

The output comparative result.

The present invention also proposes the arrangements for analyzing frequency of controlling object, please refer to Fig. 3, comprising:

Pre-configured list 301 is used for the resistance of preset LCR oscillatory circuit;

First acquiring unit 302 is used to obtain the input signal of system's controlling object;

Second acquisition unit 303 is used to obtain the output signal of system's controlling object;

First signal processing unit 304 is used for input signal is imported the LCR oscillatory circuit, and carries out obtaining first response signal after the convergence process;

Secondary signal processing unit 305 is used for the oscillatory circuit with output signal input LCR, and carries out obtaining second response signal after the convergence process;

Spectral analysis unit 306 is used for comparison first response signal and second response signal, obtains the spectrum analysis result of system's controlling object.

Apparatus of the present invention at first are provided with the resistance of LCR oscillator, and the signal amplitude of process LCR oscillatory circuit is index in time to be strengthened, and the influence of noise also just weakens gradually like this, thereby has reduced the jamtosignal of output frequency signal significantly; With the signal of LCR oscillatory circuit output, multiply by a convergence exponent function that is complementary then, finally obtain being still the signal of constant amplitude output; But the jamtosignal characteristic of signal is significantly improved, thereby under stronger noise environment, has significantly improved controlling object frequency domain characteristic identification quality, has improved the antijamming capability of system, improves the reliability of spectrum analysis.

In embodiment, pre-configured unit 301 also is used for the preset time of obtaining the input signal and the input signal of system's controlling object therein;

When Preset Time arrives, then notify spectral analysis unit to stop the current frequency spectrum analysis.

In embodiment, first signal processing unit 304 is imported the LCR oscillatory circuit with input signal therein, and when carrying out obtaining first response signal after the convergence process, input signal is imported the LCR oscillatory circuit, obtains first and disperses signal; Disperse signal times with convergent function with first, obtain first response signal;

Secondary signal processing unit 305 will be exported signal input LCR oscillatory circuit, and when carrying out obtaining second response signal after the convergence process, will export signal and import the LCR oscillatory circuit, obtain second and disperse signal; Disperse signal times with convergent function with second, obtain second response signal;

Wherein, convergent function is: ω ₀Be the centre frequency of said LCR oscillator, R is the resistance identical with the resistance of presetting the LCR oscillatory circuit, and t is the time.

Therein in embodiment, relatively first response signals and second response signal spectrum analysis as a result time that obtains system's controlling object of spectral analysis unit 306,

Obtain the amplitude information and the phase information of first response signal;

Obtain the amplitude information and the phase information of second response signal;

Compare the amplitude information of first response signal and the amplitude information of second response signal; And, compare the phase information of first response signal and the phase information of second response signal;

The output comparative result.

The above embodiment has only expressed several kinds of embodiments of the present invention, and it describes comparatively concrete and detailed, but can not therefore be interpreted as the restriction to claim of the present invention.Should be pointed out that for the person of ordinary skill of the art under the prerequisite that does not break away from the present invention's design, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with accompanying claims.

Claims (8)

1. the frequency spectrum analysis method of controlling object is characterized in that, comprises step:

The resistance of preset LCR oscillatory circuit; Wherein, the span of said resistance is: greater than-2 and less than 0;

Obtain the input signal of system's controlling object;

Obtain the output signal of system's controlling object;

Said input signal is imported said LCR oscillatory circuit, and carry out obtaining first response signal after the convergence process;

Said output signal is imported said LCR oscillatory circuit, and carry out obtaining second response signal after the convergence process;

More said first response signal and said second response signal obtain the spectrum analysis result of said system controlling object.

2. the frequency spectrum analysis method of controlling object according to claim 1 is characterized in that,

Before the step of the said input signal that obtains system's controlling object, the preset time of obtaining input signal with the output signal of system's controlling object; When Preset Time arrives, then stop the current frequency spectrum analysis.

3. the frequency spectrum analysis method of controlling object according to claim 1 is characterized in that,

Said input signal is imported said LCR oscillatory circuit, and the step of carrying out obtaining after the convergence process first response signal is specially:

Said input signal is imported said LCR oscillatory circuit, obtain first and disperse signal;

Disperse signal times with convergent function with said first, obtain said first response signal;

The said signal of will exporting is imported said LCR oscillatory circuit, and the step of carrying out obtaining after the convergence process second response signal is specially:

Said output signal is imported said LCR oscillatory circuit, obtain second and disperse signal;

Disperse signal times with convergent function with said second, obtain said second response signal;

Wherein, said convergent function is:

ω ₀Be the centre frequency of said LCR oscillator, R is the resistance identical with the resistance of said preset LCR oscillatory circuit, and t is the time.

4. according to the frequency spectrum analysis method of each described controlling object of claim 1 to 3, it is characterized in that,

The step that said comparison first response signal and said second response signal obtain the spectrum analysis result of said system controlling object comprises:

Obtain the amplitude information and the phase information of said first response signal;

Obtain the amplitude information and the phase information of said second response signal;

The amplitude information of the amplitude information of more said first response signal and said second response signal; And, the phase information of the phase information of more said first response signal and said second response signal;

The output comparative result.

5. the arrangements for analyzing frequency of controlling object is characterized in that, comprising:

Pre-configured unit is used for the resistance of preset LCR oscillatory circuit; Wherein, the span of said resistance is: greater than-2 and less than 0;

First acquiring unit is used to obtain the input signal of system's controlling object;

Second acquisition unit is used to obtain the output signal of system's controlling object;

First signal processing unit is used for said input signal is imported said LCR oscillatory circuit, and carries out obtaining first response signal after the convergence process;

The secondary signal processing unit is used for said output signal is imported said LCR oscillatory circuit, and carries out obtaining second response signal after the convergence process;

Spectral analysis unit is used for the spectrum analysis result that more said first response signal and said second response signal obtain said system controlling object.

6. the arrangements for analyzing frequency of controlling object according to claim 5 is characterized in that,

Said pre-configured unit also is used for the preset time of obtaining input signal with the output signal of system's controlling object;

When Preset Time arrives, then notify said spectral analysis unit to stop the current frequency spectrum analysis.

7. the arrangements for analyzing frequency of controlling object according to claim 5 is characterized in that,

Said first signal processing unit is imported said LCR oscillatory circuit with input signal, and when carrying out obtaining first response signal after the convergence process, said input signal is imported said LCR oscillatory circuit, obtains first and disperses signal; Disperse signal times with convergent function with said first, obtain said first response signal;

Said secondary signal processing unit will be exported signal and import said LCR oscillatory circuit, and when carrying out obtaining second response signal after the convergence process, said output signal imported said LCR oscillatory circuit, obtain second and disperse signal; Disperse signal times with convergent function with said second, obtain said second response signal;

Wherein, said convergent function is: ω ₀Be the centre frequency of said LCR oscillator, R is the resistance identical with the resistance of said preset LCR oscillatory circuit, and t is the time.

8. according to the arrangements for analyzing frequency of each described controlling object of claim 5 to 7, it is characterized in that,

The spectrum analysis that said spectral analysis unit comparison first response signal and said second response signal obtain said system controlling object is as a result the time,

Obtain the amplitude information and the phase information of said first response signal;

Obtain the amplitude information and the phase information of said second response signal;

The amplitude information of the amplitude information of more said first response signal and said second response signal; And, the phase information of the phase information of more said first response signal and said second response signal;

The output comparative result.

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