CN101510071B - Pseudo-imaginary frequency filtering control method and apparatus - Google Patents

Abstract

The embodiment of the invention discloses a pseudo-virtual-frequency filtering control method and a device thereof; the method comprises: second-order differential enveloping characteristics demodulation operation is carried out to a process input signal for obtaining a second-order differential enveloping characteristics quantity signal; the second-order differential enveloping characteristics quantity signal is multiplied by the process input signal for obtaining a real frequency item signal; and the signal obtained after a differential operation of the process input signal is subtracted by the real frequency item signal so as to obtain a pseudo-virtual-frequency signal. By adopting the embodiment of the invention, the impact of high-frequency interference on a thermal control system can be reduced, and the regulating quality of a thermal control loop can be improved.

Description

Pseudo-imaginary frequency filtering control method and device

Technical field

The present invention relates to thermal technology's control technology field, relate in particular to a kind of pseudo-imaginary frequency filtering control method and device.

Background technology

Thermal power plant's thermal technology's controlling object has characteristics such as big inertia, pure time-delay, time variation and strong nonlinearity, and because the inside and outside disturbing source of various the unknowns is constantly scurried into the object passage, the system that makes is difficult to control.How effectively to overcome the adverse effect of various inside and outside disturbances, thereby improve the regulation quality of thermal technology's control loop, be that the thermal technology controls one of target of constantly pursuing in the field always.

In the prior art, robust property is PID (Proportion Integration Differentiation preferably, proportion integration differentiation) control strategy is controlled the absolute leading position in field always in occupation of the thermal technology, for improving the controlling performance of thermal object, in regulating loop, add the differentiation element effect, can improve the response speed in loop, this is the typical method that the thermal technology controls normal employing.

The inventor is in implementing process of the present invention, find that existing P ID control strategy has following shortcoming: in the differential action item of PID regulator loop, play the anticipatory control effect be wherein empty frequently, then increased the high-frequency gain of regulator and made stability decreases frequently in fact.Therefore, the differential action item in the regulating loop is when improving dynamic performance, and its high-pass filtering characteristic has also been amplified high frequency interference, causes system to cause the fluctuation of governor motion easily when having external high frequency to disturb.

Summary of the invention

The embodiment of the invention provides a kind of pseudo-imaginary frequency filtering control method and device, can reduce the influence of high frequency interference to thermal technology's control system, improves the regulation quality of thermal technology's control loop.

The embodiment of the invention provides a kind of pseudo-imaginary frequency filtering control method, and this method comprises:

The process input signal is carried out second-order differential envelope characteristic demodulation computing, obtain second-order differential envelope characteristic amount signal;

Described second-order differential envelope characteristic amount signal and described process input signal are multiplied each other, obtain a real signal frequently;

A signal and a described real signal subtraction frequently with described process input signal is obtained after differentiating obtain pseudo-empty signal frequently;

Described pseudo-empty signal frequently is used for thermal technology's control loop, and the differential term that substitutes the PID regulator in thermal technology's control system carries out anticipatory control.

Correspondingly, the embodiment of the invention also provides a kind of pseudo-imaginary frequency filtering control device, comprising:

Second-order differential envelope characteristic demodulation module is used for the process input signal is carried out second-order differential envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal;

A real constructing module frequently is used for described second-order differential envelope characteristic amount signal and described process input signal are multiplied each other, and obtains a real signal frequently;

An empty extraction module frequently is used for a signal and a described real signal subtraction frequently that described process input signal is obtained through differentiating after, obtain pseudo-void frequency signal;

Described pseudo-imaginary frequency filtering control device is used for thermal technology's control system, adopts the differential term of the PID regulator in the pseudo-empty control system of signal substituting thermal technology frequently to carry out anticipatory control.

Implement the embodiment of the invention, have following beneficial effect:

Pseudo-imaginary frequency filtering control method that the embodiment of the invention provides and device, empty item frequently in the differential action link is leached, be applied to the process control in thermal technology's control field, can solve the contradiction between time domain closed-loop system and the frequency domain closed-loop system performance index, reduce the influence of high frequency interference, improve the regulation quality of thermal technology's control loop system.

Description of drawings

In order to be illustrated more clearly in the embodiment of the invention or technical scheme of the prior art, to do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below, apparently, accompanying drawing in describing below only is some embodiments of the present invention, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.

Fig. 1 is the schematic flow sheet of an embodiment of pseudo-imaginary frequency filtering control method provided by the invention;

Fig. 2 is the structural representation of first embodiment of pseudo-imaginary frequency filtering control device provided by the invention;

Fig. 3 is the structural representation of second embodiment of pseudo-imaginary frequency filtering control device provided by the invention;

Fig. 4 is the theoretical amplitude frequency characteristic figure of the pseudo-imaginary frequency filtering of pseudo-imaginary frequency filtering control device provided by the invention;

Fig. 5 is the pseudo-imaginary frequency filtering time domain step response figure of pseudo-imaginary frequency filtering control device provided by the invention.

Embodiment

Below in conjunction with the accompanying drawing in the embodiment of the invention, the technical scheme in the embodiment of the invention is clearly and completely described, obviously, described embodiment only is the present invention's part embodiment, rather than whole embodiment.Based on the embodiment among the present invention, those of ordinary skills belong to the scope of protection of the invention not making the every other embodiment that is obtained under the creative work prerequisite.

Referring to Fig. 1, be the schematic flow sheet of an embodiment of pseudo-imaginary frequency filtering control method provided by the invention.

The pseudo-imaginary frequency filtering control method that the embodiment of the invention provides leaches the empty item frequently in the differential action link and is used for process control, can overcome the prior art medium-high frequency and disturb shortcoming to the influence of thermal technology's control system, improves the regulation quality of thermal technology's control loop.This method comprises the steps:

S100 carries out second-order differential envelope characteristic demodulation computing to the process input signal, obtains second-order differential envelope characteristic amount signal; Specifically comprise: the process input signal is differentiated, obtain the single order differential signal; Again described single order differential signal is differentiated, obtain the second-order differential signal; Described second-order differential signal is carried out envelope characteristic demodulation computing, obtain second-order differential envelope characteristic amount signal.

S101 multiplies each other described second-order differential envelope characteristic amount signal and described process input signal, obtains a real signal frequently;

S102, a signal and a described real signal subtraction frequently with described process input signal is obtained after differentiating obtain pseudo-empty signal frequently.

More specifically, the embodiment of the invention is differentiated to process input signal X, obtains the single order differential signal; The transport function expression formula of this differentiation element is:

$G_1\left(s\right)=\frac{Y\left(s\right)}{X\left(s\right)}=\frac{{\mathrm{<figure-callout\; id="1"\; label="T\; d\; s"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_{d}s}{1+T_{d}s}$

Make s=ω j, obtain corresponding frequency-domain function expression formula and be:

$G_1\left(\mathrm{j\&omega;}\right)=\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}=\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}+\frac{T_d\mathrm{\&omega;}}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}j$

Wherein, a real function frequently is:

An empty function frequently is:

The contained real amplitude Transfer function in the frequency domain frequently of frequency domain of single order differential signal is

Further, described single order differential signal is differentiated, obtain the second-order differential signal; The pairing time-domain function expression formula of this secondary differential element is:

$G_2\left(s\right)=\frac{Y\left(s\right)}{X\left(s\right)}*\frac{Y\left(s\right)}{X\left(s\right)}={\left(\frac{{\mathrm{<figure-callout\; id="1"\; label="T\; d\; s"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_{d}s}{1+T_{d}s}\right)}^2$

Make s=ω j, obtain corresponding frequency-domain function expression formula and be:

$G_2\left(\mathrm{j\&omega;}\right)={\left(\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}\right)}^2$

The frequency domain amplitude Transfer function in the frequency domain of secondary differential element is:

$M\left(\mathrm{\&omega;}\right)=\left|G_2\left(\mathrm{j\&omega;}\right)\right|=\left|{\left(\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}\right)}^2\right|={\left|\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}\right|}^2=\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}$

Second-order differential signal frequency-domain amplitude Transfer function in the frequency domain is

Its envelope characteristic is consistent with a real function frequently of single order differential signal.Therefore, described second-order differential signal is carried out envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal, this second-order differential envelope characteristic amount signal and process input signal X are multiplied each other, can obtain a real signal frequently: $M\left(\mathrm{j\&omega;}\right)=\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}.$

Further, the single order differential signal is deducted a described real signal frequently, can obtain the empty signal frequently in the differentiation element frequency domain

As follows:

$G_1\left(\mathrm{j\&omega;}\right)-M\left(\mathrm{j\&omega;}\right)=\frac{T_d\mathrm{\&omega;}}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}j$

The pseudo-imaginary frequency filtering control method that the embodiment of the invention provides, empty item frequently in the differential action link is leached, this void is an external appearance characteristic with frequency characteristic frequently, be applied in thermal technology's control system, replace in the prior art differential action item in the PID regulator loop or be used for the anticipatory control network, to help the regulating system performance index, improve the regulation quality of thermal technology's control loop.

Referring to Fig. 2, be the structural representation of first embodiment of pseudo-imaginary frequency filtering control device provided by the invention.This device comprises: second-order differential envelope characteristic demodulation module 1, a real constructing module 2 frequently and pseudo-empty extraction module 3 frequently, wherein:

Second-order differential envelope characteristic demodulation module 1 is used for the process input signal is carried out second-order differential envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal;

A real constructing module 2 frequently is used for described second-order differential envelope characteristic amount signal and described process input signal are multiplied each other, and obtains a real signal frequently;

An empty extraction module 3 frequently is used for a signal and a described real signal subtraction frequently that described process input signal is obtained through differentiating after, obtain pseudo-void frequency signal.

Concrete, second-order differential envelope characteristic demodulation module 1 further comprises: first differentiation element, second differentiation element and envelope characteristic demodulating unit, wherein:

First differentiation element is used for the process input signal is differentiated, and obtains the single order differential signal;

Second differentiation element is used for described single order differential signal is differentiated, and obtains the second-order differential signal;

The envelope characteristic demodulating unit is used for described second-order differential signal is carried out envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal.

A described empty extraction module frequently comprises the algebraic sum circuit, the addition input end of this algebraic sum circuit inserts the single order differential signal, its subtraction input end inserts a real signal frequently, is used for a described single order differential signal and a described real signal are frequently subtracted computing, obtains pseudo-empty signal frequently.

The pseudo-imaginary frequency filtering control device that the embodiment of the invention provides, empty item frequently in the differential action link is leached, be applied to the process control in thermal technology's control field, can solve the contradiction between time domain closed-loop system and the frequency domain closed-loop system performance index, reduce the influence of high frequency interference, improve the regulation quality of thermal technology's control loop system.

Referring to Fig. 3, be the structural representation of second embodiment of pseudo-imaginary frequency filtering control device provided by the invention, this device comprises: second-order differential envelope characteristic demodulation module, a real constructing module frequently and pseudo-empty extraction module frequently; Wherein:

Second-order differential envelope characteristic demodulation module is used for the process input signal is carried out second-order differential envelope characteristic demodulation computing, obtain second-order differential envelope characteristic amount signal, specifically comprise differentiating circuit A1 and A2, circuit A3 and A5, flywheel circuit A4 and A6,0.1 constant circuit A7, algebraic sum circuit A8, divider circuit A9 and flywheel circuit A10 take absolute value;

A real constructing module frequently is used for described second-order differential envelope characteristic amount signal and described process input signal are multiplied each other, and obtains a real signal frequently, and this reality constructing module frequently comprises multiplier circuit B1;

An empty extraction module frequently is used for a signal and a described real signal subtraction frequently that described process input signal is obtained through differentiating after, obtain pseudo-empty signal frequently, and this void frequency item extraction module comprises algebraic sum circuit M1.

Below in conjunction with Fig. 3, each circuit function module of the embodiment of the invention is described:

1) differentiating circuit A1, A2 are used for input signal is differentiated, and corresponding transport function is:

$Y\left(s\right)=\left(\frac{T_d*s}{1+T_d*s}\right)X\left(s\right)$

Wherein, mark is described as shown in table 1:

The mark of table 1 differentiating circuit transport function is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Differential output
Input X	float?	0.0?	Input
				Parameter T d	float?	1.0?	Derivative time constant, necessary 〉=0, unit second

2) take absolute value circuit A3, A5 is used for a floating-point variable export in the computing that takes absolute value of input floating-point variable, and the transport function of correspondence is:

Y(n)＝|X(n)|

Wherein, mark is described as shown in table 2:

The take absolute value mark of circuit transport function of table 2 is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Absolute calculation output
Input X	float?	0.0?	Floating number immediately

3) inertia filtering circuit A4, A6, A10 are used for input signal is carried out the one order inertia computing, and corresponding transport function is:

$Y\left(s\right)=\left(\frac{1}{T_i*s+1}\right)X\left(s\right)$

Wherein, mark is described as shown in table 3:

The mark of table 3 flywheel circuit transport function is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Inertia output
Input X	float?	0.0?	Input
				Parameter Ti	float?	1.0?	Inertia time constant, necessary 〉=0, unit second

4) 0.1 constant circuit A7 is used to export a floating point real number.

Mark is described as shown in table 4:

The mark of table 4 constant block circuit transport function is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Floating point real number

5) algebraic sum circuit A8, M1 are used for a floating-point variable is exported in the computing that adds deduct of two floating-point variables, and corresponding transport function is:

Y(n)＝A(n)±B(n)

Wherein, mark is described as shown in table 5:

The mark of table 5 algebraic sum circuit transport function is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Addition output
Input A, B	float?	0.0?	Floating number immediately

6) divider circuit A9 is used for two floating-point variables are made division arithmetic, exports a floating-point variable, and corresponding transport function is:

Y(n)＝X1(n)/X2(n)

Wherein, mark is described as shown in table 6:

The mark of table 6 divider circuit transport function is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Division output
Input X1, X2	float?	1.0，1.0?	Floating number immediately

7) multiplier circuit B1 is used for two floating-point variables are done multiplying, exports a floating-point variable, and corresponding transport function is:

Y(n)＝X1(n)*X2(n)

Mark is described as shown in table 7:

The mark of table 7 multiplier circuit transport function is described

Token name	Data type	Default value	Describe
				Output Y	float?	0.0?	Multiplication output
Input X1, X2	float?	1.0，1.0?	Floating number immediately

For convenience of description, be that sine wave signal is that example is described only below with the process input signal, the expression formula of this process input signal is X (t)=Asin (ω t), wherein, the amplitude of the symbol in this expression formula " A " expression sine wave signal, increased amplitude A in the following part expression formula, and in fact, implicit amplitude A in the Transfer function in the frequency domain.

As shown in Figure 3, in second-order differential envelope characteristic demodulation module, behind the second-order differential circuit that process input signal X process differentiating circuit A1, A2 are constituted, obtain the second-order differential signal; After this second-order differential signal passes through take absolute value circuit A3 and inertia filtering circuit A4, receive the dividend end of divider circuit A9; After process input signal X passes through take absolute value circuit A5, inertia filtering circuit A6, receive the positive input terminal of algebraic sum circuit A8; 0.1 the output terminal of constant circuit A7 is also received another positive input terminal of algebraic sum circuit A8; The divisor end of divider circuit A9 is received in the output of algebraic sum circuit A8, and the output of divider circuit A9 is behind inertia filtering circuit A10, and the character of output signal is: the envelope characteristic amount signal of secondary differential element.

Wherein, behind the process input signal X process differentiating circuit A1, the frequency-domain function expression formula of A1 output signal is:

$A1\left(\mathrm{j\&omega;}\right)=A*\frac{{\mathrm{<figure-callout\; id="1"\; label="T\; d"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+{\mathrm{<figure-callout\; id="1"\; label="T\; d"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_d\mathrm{\&omega;j}}=A*\frac{{\left({\mathrm{<figure-callout\; id="1"\; label="T\; d"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_d\mathrm{\&omega;}\right)}^2}{1+{\left({\mathrm{<figure-callout\; id="1"\; label="T\; d"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_d\mathrm{\&omega;}\right)}^2}+A*\frac{{\mathrm{<figure-callout\; id="1"\; label="T\; d"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_d\mathrm{\&omega;}}{1+{\left({\mathrm{<figure-callout\; id="1"\; label="T\; d"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">T</figure-callout>}}_d\mathrm{\&omega;}\right)}^2}j$

The output of differentiating circuit A1 inserts differentiating circuit A2, makes T _D1=T _D2=T _d, then the frequency-domain function expression formula of A2 output signal is:

$A2\left(\mathrm{j\&omega;}\right)=A*{\left(\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}\right)}^2$

The output signal of differentiating circuit A2 is behind take absolute value circuit A3 and flywheel circuit A4, and the frequency-domain function expression formula of A4 output signal is:

$A4\left(\mathrm{j\&omega;}\right)=|A*{\left(\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}\right)}^2|*\frac{1}{1+T_{i4}\mathrm{\&omega;j}}=\left|A\right|*\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}*\frac{1}{1+T_{i4}\mathrm{\&omega;j}}$

After process input signal X handled through take absolute value circuit A5 and inertia filtering circuit A6, the frequency-domain function expression formula of the output signal of A6 was:

$A6\left(\mathrm{j\&omega;}\right)=\left|A\right|*\frac{1}{1+T_{i6}\mathrm{\&omega;j}}$

The positive input terminal of algebraic sum circuit A8 is received in the output of inertia filtering circuit A6, and another positive input terminal of algebraic sum circuit A8 is also received in the output of 0.1 constant circuit A7, and the divisor end of divider circuit A9 is received in algebraic sum circuit A8 output.Need to prove that 0.1 constant circuit A7 is only for satisfying practical engineering application design, and is non-vanishing with the divisor that guarantees divider circuit A9, therefore, makes A8 (j ω)=A6 (j ω), then divider circuit A9 is output as:

$A9\left(\mathrm{j\&omega;}\right)=\frac{A4\left(\mathrm{j\&omega;}\right)}{A8\left(\mathrm{j\&omega;}\right)}=\frac{A4\left(\mathrm{j\&omega;}\right)}{A6\left(\mathrm{j\&omega;}\right)}=\frac{\left|A\right|*\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}*\frac{1}{1+T_{i4}\mathrm{\&omega;j}}}{\left|A\right|*\frac{1}{1+T_{i6}\mathrm{\&omega;j}}}=\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}*\frac{1+T_{i6}\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_{i4}\mathrm{\&omega;j}}$

Make T _I4=T _I6, then following formula becomes:

$A9\left(\mathrm{j\&omega;}\right)=\frac{A4\left(\mathrm{j\&omega;}\right)}{A6\left(\mathrm{j\&omega;}\right)}=\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}$

The character of divider circuit A9 output signal is: the envelope characteristic amount signal of secondary differential element.

Inertia filtering circuit A10 is provided with in order to satisfy practical engineering application, be used for carrying out further level and smooth to the envelope characteristic amount signal of secondary differential element, therefore, the output character of the output signal of divider circuit A9 behind inertia filtering circuit A10 still is: the envelope characteristic amount signal of secondary differential element.

In a real constructing module frequently, the multiplicand termination of multiplier circuit B1 is gone into the process input signal, and the multiplier end is connected with the output terminal of second-order differential envelope characteristic demodulation module, and then the output signal of multiplier circuit B1 is:

$B1\left(\mathrm{j\&omega;}\right)=A*\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}$

The output character of multiplier circuit B1 is: a real signal frequently.

In a void frequency extraction module, the process input signal is received the addition input end of algebraic sum circuit M1 behind differentiating circuit A1, the subtraction input end of algebraic sum circuit M1 is received in the output of multiplier circuit B1, be that algebraic sum circuit M1 is used for a single order differential signal and a real signal are frequently subtracted computing, then the output signal of algebraic sum circuit M1 is:

$M1\left(\mathrm{j\&omega;}\right)=A*\frac{T_d\mathrm{\&omega;<figure-callout\; id="1"\; label="j"\; filenames="H200910037945XE00012.png,H200910037945XE00021.png"\; state="\{\{state\}\}">j</figure-callout>}}{1+T_d\mathrm{\&omega;j}}-A*\frac{{\left(T_d\mathrm{\&omega;}\right)}^2}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}=A*\frac{T_d\mathrm{\&omega;}}{1+{\left(T_d\mathrm{\&omega;}\right)}^2}j$

The output character of algebraic sum circuit M1 is: pseudo-empty signal frequently.

In embodiments of the present invention, differentiating circuit A1, A2 and inertia filtering circuit A4, A6, A10 need carry out parameter adjustment, and wherein, differentiating circuit A1 is identical with the A2 derivative constant, i.e. T _D1=T _D2=T _d, inertia filtering circuit A4 is identical with the A6 inertia constant and equal derivative constant, i.e. T _I4=T _I6=T _d, inertia filtering circuit A10 inertia constant is 1.666 times of derivative constant, i.e. T _I10=1.666T _d

Referring to Fig. 4, be the theoretical amplitude frequency characteristic figure of pseudo-imaginary frequency filtering of the pseudo-imaginary frequency filtering control device that provides of the embodiment of the invention.

The theoretical amplitude Transfer function in the frequency domain of the pseudo-imaginary frequency filtering control device that the embodiment of the invention provided is:

Its center periodic quantity is 2 π T _d, value off period when output drops to 0.707 times of center gain is respectively 0.83 π T _dWith 4.82 π T _d

If the derivative constant of differentiating circuit A1 and A2 is 30s, the inertia constant of inertia filtering circuit A4 and A6 is 30s, and the inertia constant of inertia filtering circuit A10 is 50s.When the process input signal is sine function, be: X (t)=Asin (ω t), then the theoretical center periodic quantity is 188.5s, and the theoretical cutoff periodic quantity when output amplitude drops to 0.707 times of center gain is respectively: 78.3s, 454.3s, its theoretical amplitude frequency characteristic as shown in Figure 4.

Still by the above-mentioned physical circuit parameter that provides, when the process input signal is step function, promptly

Then pseudo-imaginary frequency filtering time domain rank characteristic as shown in Figure 5.

In the middle of concrete enforcement, the pseudo-imaginary frequency filtering control device that the embodiment of the invention provides can be applicable in the thermal technology of the thermal power plant control system, replace in the prior art differential action item in the PID regulator loop or be used for the anticipatory control network, to help the regulating system performance index, improve the regulation quality of thermal technology's control loop.

In the prior art, conventional PID control strategy is adopted in the adjusting of the boiler overheating steam temperature of thermal power plant, and in the differential term of PID regulator loop, its void item frequently can play the anticipatory control effect, and real item has frequently then increased the high-frequency gain of regulator and made stability decreases.Therefore, the differential action item in the regulating loop is when improving dynamic performance, and its high-pass filtering characteristic has also been amplified high frequency interference, causes system to cause the fluctuation of governor motion easily when having external high frequency to disturb.Adopt the embodiment of the invention, introducing the pseudo-imaginary frequency filtering control device in existing main control loop is optimized, adopt the differential term in the pseudo-imaginary frequency filtering signal replacement homophony PID controller, can improve the regulation quality of Superheated Steam Temperature Control System Applied, reduce the dynamic disturbances amplitude of governor motion, and make controlled parameter transition than more steady before optimizing.

Pseudo-imaginary frequency filtering control method that the embodiment of the invention provides and device, empty item frequently in the differential action link is leached, be applied to the process control in thermal technology's control field, can solve the contradiction between time domain closed-loop system and the frequency domain closed-loop system performance index, reduce the influence of high frequency interference, improve the regulation quality of thermal technology's control loop system.

Through the above description of the embodiments, those skilled in the art can be well understood to the present invention and can realize by the mode that software adds essential hardware platform, can certainly all implement by hardware.Based on such understanding, all or part of can the embodying that technical scheme of the present invention contributes to background technology with the form of software product, this computer software product can be stored in the storage medium, as ROM/RAM, magnetic disc, CD etc., comprise that some instructions are with so that a computer equipment (can be a personal computer, server, the perhaps network equipment etc.) carry out the described method of some part of each embodiment of the present invention or embodiment.

The above is a preferred implementation of the present invention; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the principle of the invention; can also make some improvements and modifications, these improvements and modifications also are considered as protection scope of the present invention.

Claims (6)

1. a pseudo-imaginary frequency filtering control method is characterized in that, comprising:

The process input signal is carried out second-order differential envelope characteristic demodulation computing, obtain second-order differential envelope characteristic amount signal;

Described second-order differential envelope characteristic amount signal and described process input signal are multiplied each other, obtain a real signal frequently;

A signal and a described real signal subtraction frequently with described process input signal is obtained after differentiating obtain pseudo-empty signal frequently;

Described pseudo-empty signal frequently is used for thermal technology's control loop, and the differential term that substitutes the PID regulator in thermal technology's control system carries out anticipatory control.

2. pseudo-imaginary frequency filtering control method as claimed in claim 1 is characterized in that, described the process input signal is carried out second-order differential envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal, comprising:

The process input signal is differentiated, obtain the single order differential signal;

Described single order differential signal is differentiated, obtain the second-order differential signal;

Described second-order differential signal is carried out envelope characteristic demodulation computing, obtain second-order differential envelope characteristic amount signal.

3. pseudo-imaginary frequency filtering control method as claimed in claim 2 is characterized in that, a signal and a described real signal subtraction frequently with described process input signal is obtained after differentiating obtain pseudo-empty signal frequently, comprising:

With a described single order differential signal and a described real signal subtraction frequently, obtain the pseudo-empty signal frequently in the described single order differential signal frequency domain.

4. a pseudo-imaginary frequency filtering control device is characterized in that, comprising:

Second-order differential envelope characteristic demodulation module is used for the process input signal is carried out second-order differential envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal;

A real constructing module frequently is used for described second-order differential envelope characteristic amount signal and described process input signal are multiplied each other, and obtains a real signal frequently;

An empty extraction module frequently is used for a signal and a described real signal subtraction frequently that described process input signal is obtained through differentiating after, obtain pseudo-void frequency signal;

Described pseudo-imaginary frequency filtering control device is used for thermal technology's control system, adopts the differential term of the PID regulator in the pseudo-empty control system of signal substituting thermal technology frequently to carry out anticipatory control.

5. pseudo-imaginary frequency filtering control device as claimed in claim 4 is characterized in that, described second-order differential envelope characteristic demodulation module specifically comprises:

First differentiation element is used for the process input signal is differentiated, and obtains the single order differential signal;

Second differentiation element is used for described single order differential signal is differentiated, and obtains the second-order differential signal;

The envelope characteristic demodulating unit is used for described second-order differential signal is carried out envelope characteristic demodulation computing, obtains second-order differential envelope characteristic amount signal.

6. pseudo-imaginary frequency filtering control device as claimed in claim 5 is characterized in that, a described empty extraction module frequently comprises:

The algebraic sum circuit is used for a described single order differential signal and a described real signal are frequently subtracted computing, obtains pseudo-empty signal frequently.

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