CN103197692A - Method, device and system for flow control - Google Patents

Abstract

The invention discloses a method, device and system for flow control. According to the core idea of the method, device and system for the flow control, a data set formed by flow of liquid or gas and control parameters is taken as a base, two parameters are obtained by means of least square operation, the corresponding linear relation between the flow of the liquid or the gas and the control parameters is obtained through the two parameters, and then a corresponding control parameter can be obtained according to the corresponding linear relation between the flow of the liquid or the gas and the control parameters under the condition that the flow of the liquid or the gas is available. Therefore, the proportion integration differentiation (PID) control method or other control methods are not needed for finding out size of the control parameters, and thus the over-control phenomenon caused by the PID control method is avoided. According to the method, device and system for the flow control, the flow of the liquid or the gas can be controlled accurately, stable, real-time and reliable flow control can be achieved, and technological requirements and enterprise expectations are met.

Description

A kind of flow control methods, Apparatus and system

Technical field

The invention belongs to automatic field, particularly a kind of flow control methods, Apparatus and system.

Background technology

In the system for liquid and air supply system of metallurgy industry, raising along with technology lifting and automatic controlling level, to more and more stricter with control accuracy and the real-time requirement of gas supply flow for liquid, but because equipment itself reasons such as layout of (as the inherent characteristics such as dead band of variable frequency pump and valve body for liquid) and process pipeline, determined system and air supply system for liquid be one non-linear and have a system of large time delay.How under such large time delay, nonlinear operating mode, realize stable, real-time, flow control reliably? people have carried out research and the practice of various control strategy to this, and comparatively advanced, adopt most often proportional-integral-differential (Proportion Integration Differentiation, PID) control mode.

Pid control mode has been realized rapid adjustment in production application, but pid control mode but can't satisfy not only fast but also stable adjusting simultaneously in this Large-lag System, particularly when operating mode is changeable, the phenomenon that overshoot often occurs, thereby produce significantly vibration, the control effect is obviously reduced.

For example: in actual applications, adopt pid control mode control liquid or gas flow, if need flow value this moment is liquid or the gas of X, then flow value X is the desired value in the pid control mode, when adopting pid control mode control, will regulate according to the flow value of liquid or gas in preceding pipeline, if X is little than the desired value flow, to increase the output quantity of liquid or gas so, and namely increase the valve position opening degree of control liquid or gas flow, or choose the variable frequency pump frequency; If output quantity is still little than desired value flow X, then continue to increase the valve position opening degree, or choose the variable frequency pump frequency, after output quantity has satisfied desired value X, just stop to increase the valve position opening degree or choose the variable frequency pump frequency, continue to adopt current valve position opening degree or the variable of variable frequency pump frequency control liquid or gas then, but because the hysteresis quality of system, under current valve position opening degree or variable frequency pump frequency, the output quantity of liquid or gas can continue to choose greatly, causes liquid or gas flow value the phenomenon of overshoot to occur greater than desired value.

If bigger than desired value, the phenomenon of overshoot also can appear in the process of using pid control mode to control.

Since in the prior art when needing flow value to be the liquid of X or gas, do not know the valve position opening degree, or the variable frequency pump frequency should just can reach required flow value for what, therefore use pid control mode to control, in order to make valve position opening degree or variable frequency pump frequency can produce liquid or the gas that required flow value is X, but because pid control mode itself has the defective of certain hysteresis quality, the value of feedback of the system for liquid of metallurgy industry and air supply system also has bigger hysteresis quality in addition, when therefore adopting pid control mode control liquid or gas flow, the over-control that output quantity exceeds desired value often appears, cause controlling poor effect, and having caused unnecessary waste, the expection of this and technological requirement and enterprise is not inconsistent.

Therefore how to adopt a kind of new flow control mode, under the operating mode of such large time delay, realize that stable, real-time, flow control reliably becomes the present stage urgent problem.

Summary of the invention

Given this, the present invention proposes a kind of flow control methods, Apparatus and system, be used for liquid with precise control or gas flow, realize stable, real-time, flow control reliably, meet the expection of technological requirement and enterprise.

A kind of flow control methods comprises:

Obtain default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation;

Wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2;

Wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula:

Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

Make up linear equation Y=aX+b by described parameter a and described parameter b;

Obtain required liquid or gas flow X1;

According to described linear equation Y=aX+b, obtain the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow.

A kind of flow control methods comprises:

Obtain default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1M, or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number;

According to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

Obtain and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁

Wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula:

Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y;

According to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁

By the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Obtain required liquid or gas flow X2;

Judge the k interval that liquid or gas flow X2 are affiliated;

Obtain linear equation Y=a according to described k interval _kX+b _k

According to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow.

A kind of volume control device comprises:

Parameter calculation unit is used for obtaining default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation, wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2, and wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i\right)\stackrel{\‾}{Y}}{\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i\right)\stackrel{\‾}{X}}=,$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\‾}{Y}-a\stackrel{\‾}{X}=,$ Wherein, Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

The first equation acquiring unit is used for making up linear equation Y=aX+b by described parameter a and described parameter b;

First acquiring unit is used for obtaining required liquid or gas flow X1, according to described linear equation Y=aX+b, obtains the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow.

A kind of volume control device comprises:

Choose the unit, be used for obtaining default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1MX _1M, or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number;

Second acquisition unit is used for according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

The second equation acquiring unit is used for obtaining and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁, wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{M+2}{\mathrm{\Σ}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\Σ}}}{X}_i\right)\stackrel{\‾}{Y}}{\left(\underset{i=1}{\overset{M+2}{\mathrm{\Σ}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\Σ}}}{X}_i\right)\stackrel{\‾}{X}}=,$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\‾}{Y}-a\stackrel{\‾}{X}=,$ Wherein, Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y, according to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁, by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Third party's journey acquiring unit is used for obtaining required liquid or gas flow X2, judges the k interval that liquid or gas flow X2 are affiliated, obtains linear equation Y=a according to described k interval _kX+b _k

The 3rd acquiring unit is used for according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow.

A kind of flow control system comprises:

First processor is used for obtaining default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation, wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2, and wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i\right)\stackrel{\‾}{Y}}{\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i\right)\stackrel{\‾}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\‾}{Y}-a\stackrel{\‾}{X}=,$ Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

First controller, be used for making up linear equation Y=aX+b by described parameter a and described parameter b, obtain required liquid or gas flow X1, according to described linear equation Y=aX+b, obtain the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow;

First equipment to be controlled is used for linking to each other with described first controller, receives the control parameter Y1 of described liquid or gas flow, and carries out corresponding operating according to described control parameter Y1.

A kind of flow control system comprises:

Second processor is used for obtaining default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1MOr at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M is natural number, according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y1 _j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number, obtain and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁With parameter b 1, wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula:

Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y, according to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁, by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Second controller is used for obtaining required liquid or gas flow X2, judges the k interval that liquid or gas flow X2 are affiliated, obtains linear equation Y=a according to described k interval _kX+b _k, according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow;

Second equipment to be controlled is used for linking to each other with described second controller, receives the control parameter Y2 of described liquid or gas flow, and carries out corresponding operating according to described control parameter Y2.

The invention provides two kinds of flow control methods, its core concept all is that the data group formed with the flow of predefined liquid or gas and control parameter is as the basis, utilize least square method to carry out computing and obtain two parameters, obtain the flow of liquid or gas and the linear relationship between the control parameter by described two parameters.And according to liquid or gas flow and the linear relationship of control between the parameter, obtain the value of the control parameter corresponding with the value of the flow of required liquid or gas.Thereby needn't adopt pid control mode or other control modes to go to explore the size of control parameter, and then can not produce PID control over-control, thereby realize stable, flow control reliably, meet the expection of technological requirement and enterprise.

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 process flow diagram of the disclosed flow control methods of the embodiment of the invention;

Fig. 2 is the structural representation of PLC controller in the disclosed flow control methods of the embodiment of the invention;

Fig. 3 is the process flow diagram of the disclosed another flow control methods of the embodiment of the invention;

Fig. 4 is the disclosed flow control methods linear equation of embodiment of the invention synoptic diagram;

Fig. 5 is the disclosed another flow control methods of the embodiment of the invention;

Fig. 6 is the disclosed another flow control methods of the embodiment of the invention;

Fig. 7 is the disclosed flow control methods linear equation of embodiment of the invention synoptic diagram;

Fig. 8 is the structural representation of the disclosed volume control device of the embodiment of the invention;

Fig. 9 is the structural representation of the disclosed another volume control device of the embodiment of the invention;

Figure 10 is the structural representation of the disclosed flow control system of the embodiment of the invention;

Figure 11 is the structural representation of the disclosed another flow control system of the embodiment of 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 obtains under the creative work prerequisite.

Before introducing the present invention in detail, introduce least square method in detail, so that the reader can better understand implementation procedure of the present invention.

Least square method (claiming least square method again) is a kind of mathematical optimization technology.It seeks the optimal function coupling of data by the quadratic sum of minimum error.Utilize least square method can try to achieve unknown data easily, and make the quadratic sum of error between data that these are tried to achieve and the real data for minimum.

(X during mutual relationship between Y), can obtain a series of paired data (X usually to study two variablees at us ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _m, Y _m); These data are depicted in the X-Y rectangular coordinate system, if find that these points near straight line, can make this straight-line equation as (formula 1-1).

Yj=aX+b ... (formula 1-1)

Wherein: a, b are any real numbers, and Yj is calculated value.

Will determine parameter a and parameter b for setting up this straight-line equation, use " principle of least square method ", with the quadratic sum [(Yi – Yj) of the deviation (Yi-Yj) of measured value Yi and theoretical value Yj ²] minimum is " optimization criterion ".

Order:

(formula 1-2)

Getting in (formula 1-1) substitution (formula 1-2):

(formula 1-3)

When ∑ (Yi-Yj) square hour, available functions

A, b are asked partial derivative, make these two partial derivatives equal zero.

M b+(∑ Xi) a=∑ Yi ... (formula 1-4)

(∑ Xi) b+(∑ Xi ²) the a=∑ (Xi, Yi) ... (formula 1-5)

Two that obtain is two system of equations of unknown number about a, b, separates these two system of equations and draws:

B=(∑ Yi)/m-a(∑ Xi)/m ... (formula 1-6)

A=[m ∑ XiYi-(∑ Xi ∑ Yi)]/[m ∑ Xi ²-(∑ Xi) ²)] ... (formula 1-7)

That is:

$b=\stackrel{\‾}{y}-l\stackrel{\‾}{x}$ (formula 1-8)

$a=\frac{\left(\mathrm{\Σxy}\right)-\left(\mathrm{\Σx}\right)\stackrel{\‾}{y}}{\left(\mathrm{\Σ}{x}^2\right)-\left(\mathrm{\Σx}\right)\stackrel{\‾}{x}}$ (formula 1-9)

At this moment in a, the b substitution (formula 1-1), (the formula 1-1) of this moment is exactly first linear equation that we return.

The invention provides two kinds of flow control methods, its core concept all is that the data group formed with the flow of liquid or gas and control parameter is as the basis, utilize least square method to carry out computing and obtain two parameters, obtain the flow of liquid or gas and the linear relationship between the control parameter by described two parameters.And according to liquid or gas flow and the linear relationship of control between the parameter, just can obtain the value of the control parameter of correspondence with it according to the value of the flow of required liquid or gas.Thereby needn't adopt pid control mode or other control modes to go to explore the size of control parameter, thereby the over-control that can pid control mode produce.In the following embodiments, will be described in detail one by one.

As shown in Figure 1, the invention provides a kind of flow control methods, comprising:

Step 101: obtain default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation; Namely adopt least square method get parms a and parameter b;

Wherein default N organizes data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) acquisition process comprise: according to liquid in the actual conditions or the gas flow X magnitude relationship with the control parameter Y of the described liquid of control or gas flow X, obtain N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), i=1,2 wherein ... N, N are natural number and N 〉=2;

Control parameter Y comprises: valve position opening degree or variable frequency pump frequency, valve position and variable frequency pump all are the controllers of control flow, when increasing delivery rate, the valve position opening degree chooses, when reducing delivery rate, the valve position opening degree reduces, in like manner, choose when variable frequency pump frequency selection purposes delivery rate, reduce when the variable frequency pump frequency reduces delivery rate.

According to liquid in the actual conditions or the gas flow X relation with the control parameter Y of the described liquid of control or gas flow X, namely under the certain situation of valve position opening degree, the valve position opening degree of the output quantity of actual measurement liquid or gas and this moment, under the certain situation of variable frequency pump frequency, actual measurement liquid or gas output quantity and the variable frequency pump frequency of this moment.

Be example with the valve position opening degree: when actual measurement, minimum value and peaked situation according to the valve position opening degree, reach an opening degree Y by valve positioner control valve position, after waiting for that liquid or gas flow are stable, read liquid or gas flow under the current opening degree by transmitter, and record this moment transmitter reading X, and then obtain these group data (X, Y).

According to said method, the order that increases progressively with the valve position opening degree increases valve position opening degree Y successively in principle _i, and according to valve position opening degree Y _iRecord the reading X of transmitter successively _i, and then obtain N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), i=1,2 wherein ... N, N are natural number and N 〉=2, are understandable that, the follow-up linear equation that obtains of the more big the present invention of N is closing to reality more.

Be understandable that, valve position opening degree in the N group data can be in the middle of valve position opening degree minimum value and maximal value and is evenly distributed, valve position opening degree higher limit and lower limit that also can be according to actual needs, in the middle of higher limit and lower limit, be and be evenly distributed, what certainly can understand is, it is in order to make this curve can be suitable for whole liquid or gas flow that the threshold value opening degree is averaged value, thereby can't too concentrate make the curve that finally obtains produce bigger error owing to value, can certainly be as required to the inhomogeneous value of carrying out of the valve position opening degree in the N group data.Do not do restriction at this.

When control variable was the variable frequency pump frequency, employed method was the same, according to variable frequency pump frequency Y _iX with liquid or gas under this frequency _iFlow, obtain N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), i=1,2 wherein ... N, N are natural number and N 〉=2.

Wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula: Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X, Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

The formula of least square method is primarily aimed at the linear equation of Y=aX+b form, at first according to N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) obtain the mean value of liquid or gas flow X

According to N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) mean value of controlled parameter Y

Then according to the formula of calculating parameter a in the least square method N is organized data liquid or gas flow X and the value of controlling parameter Y, and N group data obtain the mean value of liquid or gas flow X

The mean value of the controlled parameter Y of N group data

In the formula of substitution calculating parameter a, calculate the value of parameter a.

According to the formula that calculates parameter b in the least square method formula

With the value of parameter a, N group data obtain the mean value of liquid or gas flow X

The mean value of the controlled parameter Y of N group data

In the formula of substitution calculating parameter b, calculate the value of parameter b.

This parameter a and parameter b are a and b among the thread equation Y=aX+b.

Step 102: make up linear equation Y=aX+b by described parameter a and described parameter b; Namely make up linear equation by parameter a and parameter b.

Can obtain linear equation Y=aX+b by the parameter a that obtains in the above-mentioned steps and parameter b.In working control, the present invention adopts programmable logic controller (PLC) (Programmable Logic Controller, PLC) Bian Cheng mode realizes linear equation Y=aX+b by parameter a and parameter b, and realizes input quantity X(liquid or gas flow X) to output quantity Y(control parameter) process.

By shown in Figure 2, the present invention realizes the function of linear equation Y=aX+b by the PLC controller, concrete, the value that above-mentioned steps is obtained parameter a inputs to pin a, the value of parameter b is inputed to pin b, liquid or gas flow are imported by pin X, exported the value of control variable Y then by pin Y.

Step 103: obtain required liquid or gas flow X1;

According to the needed liquid of actual conditions or gas flow X1, be understandable that if required liquid or gas flow X1 changes according to certain rules, then obtain liquid or gas flow X1 by certain Changing Pattern, and the value of flow X1 is sent to the pin X input end of PLC controller.

Step 104: according to described linear equation Y=aX+b, obtain the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow; Namely calculate control parameter Y1 by linear equation.

Present embodiment provides flow control methods, organize data as the basis with default N, utilize least square method to carry out computing and obtain two parameter a and b, make up a linear equation by parameter a and b, be i.e. linear relationship between the flow of the liquid of N group data or gas and the control parameter.According to the linear relationship between liquid or gas flow and the control parameter, obtain the value Y1 of corresponding with it control parameter according to the value X1 of the flow of required liquid or gas.Thereby needn't adopt pid control mode or other control modes to go to explore the size of control parameter, thus the over-control that can pid control mode produce, realize stable, in real time, flow control reliably, meet the expection of technological requirement and enterprise.

Adopt the content of concrete above-described embodiment of scene embodiment to be described in detail below.

As shown in Figure 3, the invention provides the scene embodiment of flow control methods, comprising:

Step S201: obtain eight groups of data groups under the actual conditions;

Adopt the mode of open loop control to take liquid under the actual conditions or the value Y of gas flow X and control variable, present embodiment is example with electric control valve and liquid, and present embodiment adopts N=8 to organize data instance, according to a valve position opening degree Y _i, wait the reading X of fluid flow transmitter then _iAfter stable, write down this group data, in principle, test with the order that the valve position opening degree increases progressively, obtain 8 groups of data (X then _i, Y _i), as (1.1,1.5), (2.2,3.5), (3.3,4.2), (4.4,5.0), (5.5,5.8), (6.6,7.5), (7.7,8.0) and (8.8,9.0).

What the valve position opening degree in the N group data in the present embodiment adopted is in valve position opening degree minimum value and maximal value intermediate means value, make valve position opening degree and minimum value and maximal value be the form that is evenly distributed, to average the advantage of value be to make this curve can be suitable for the flow of whole liquid to the valve position opening degree in the present embodiment, thereby can't too concentrate the feasible bigger error of curve generation that finally obtains owing to value, actual production is impacted.

Need to prove, valve position opening degree Y and fluid flow X should be complete one-to-one relationships, be Y=X but because the relation of hardware in the actual conditions, can not accomplish that valve position opening degree and fluid flow X are in full accord, above-mentioned eight groups of data for what obtain according to a certain machine, are understandable that, these data are one group of general data, may obtain other data by other machines.

Step S202: adopt least square method calculating parameter a and parameter b;

The process of calculating parameter a and parameter b is as follows:

1. foundation

Calculate the mean value of liquid or gas flow X

By eight groups of data (1.1,1.5), (2.2,3.5), (3.3,4.2), (4.4,5.0), (5.5,5.8), (6.6,7.5), (7.7,8.0) and (8.8,9.0) obtain wherein liquid or the value of gas flow X: 1.1,2.2,3.3,4.4,5.5,6.6,7.7,8.8, got by formula:

$\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i=\underset{i=1}{\overset{8}{\mathrm{\Σ}}}(1.1+2.2+3.3+4.4+5.5+6.6+7.7+8.8)=39.6\·\·\·\·\·\·\·\·\·\·\·\·\·\·\·\·\·\·\left(1\right)$

$\stackrel{\‾}{X}=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{X}_i/N=\underset{i=1}{\overset{8}{\mathrm{\Σ}}}(1.1+2.2+3.3+4.4+5.5+6.6+7.7+8.8)/8=4.95\·\·\·\·\·\·\·\·\·\·\·\·\left(2\right)$

2. foundation

Calculate the mean value of control parameter Y

By 8 groups of data (1.1,1.5), (2.2,3.5), (3.3,4.2), (4.4,5.0), (5.5,5.8), (6.6,7.5), (7.7,8.0) and (8.8,9.0) obtain wherein liquid or the value of gas flow X: 1.5,3.5,4.2,5.0,5.8,7.5,8.0,9.0, got by formula:

$\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{Y}_i=\underset{i=1}{\overset{8}{\mathrm{\Σ}}}(1.5+3.5+4.2+5.0+5.8+7.5+8.0+9.0)=44.5\·\·\·\·\·\·\·\·\·\·\·\·\left(3\right)$

$\stackrel{\‾}{Y}=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}{Y}_i/N=\underset{i=1}{\overset{8}{\mathrm{\Σ}}}(1.5+3.5+4.2+5.0+5.8+7.5+8.0+9.0)/8=5.5625\·\·\·\·\·\·\·\·\·\·\·\·\·\left(4\right)$

3. calculate $\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i,\underset{i=0}{\overset{\mathrm{<figure-callout\; id="2"\; label="N\; X\; i"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">N</figure-callout>}}{\mathrm{\&Sigma;}}}{X_i}^{}{{}_{}}^2$

$\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i=\underset{i=1}{\overset{8}{\mathrm{\&Sigma;}}}(X_1{\mathrm{<figure-callout\; id="1"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_1+X_2{\mathrm{<figure-callout\; id="2"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_2+X_3{\mathrm{<figure-callout\; id="3"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_3+X_4{\mathrm{<figure-callout\; id="4"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_4+X_5{\mathrm{<figure-callout\; id="5"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_5+X_6{\mathrm{<figure-callout\; id="6"\; label="Y"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">Y</figure-callout>}}_6+X_7{\mathrm{<figure-callout\; id="7"\; label="Y"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">Y</figure-callout>}}_7+X_8{Y}_8)$

$=1.1\&times;1.5+2.2\&times;3.5+3.3\&times;4.2+4.4\&times;5.0+5.5\&times;5.8+6.6\&times;7.5+7.7\&times;8.0+8.8\&times;9.0$

$=267.41\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(5\right)$

$\underset{i=0}{\overset{\mathrm{<figure-callout\; id="2"\; label="N\; X\; i"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">N</figure-callout>}}{\mathrm{\&Sigma;}}}{X_i}^{}{{}_{}}^2=\underset{i=1}{\overset{8}{\mathrm{\&Sigma;}}}({{\mathrm{<figure-callout\; id="1"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_1}^2+{{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_2}^2+{{\mathrm{<figure-callout\; id="3"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_3}^2+{{\mathrm{<figure-callout\; id="4"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_4}^2+{{\mathrm{<figure-callout\; id="5"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_5}^2+{{\mathrm{<figure-callout\; id="6"\; label="X"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">X</figure-callout>}}_6}^2+{{\mathrm{<figure-callout\; id="7"\; label="X"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">X</figure-callout>}}_7}^2+{{\mathrm{<figure-callout\; id="8"\; label="X"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">X</figure-callout>}}_8}^2)$

$=1.1\&times;1.1+2.2\&times;2..2+3.3\&times;3.3+4.4\&times;4.4+5.5\&times;5.5+6.6\&times;6.6+7.7\&times;7.7+8.8\&times;8.8$

$=246.84\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(6\right)$

4. with in formula (1) (2) (3) (4) (5) and (6) the substitution formula calculating parameter a formula

$a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}}=0.927,$

5. calculating parameter b is with formula (1) (2) and parameter a, in the substitution formula

$b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=0.971$

Step S203: namely make up linear equation by parameter a and parameter b.

The above-mentioned parameter a=0.927 that calculates and parameter b=0.971 obtain linear equation, Y=0.927X+0.971.

Step S204: the flow X1 that obtains required liquid.

Step S205: calculate control parameter Y1.

The value of the valve position opening degree of this moment will be obtained among the needed flow X1 substitution linear equation Y=0.927X+0.971.

As shown in Figure 4, be the linear equation that present embodiment adopts software emulation to obtain, its cathetus is for obtaining linear equation, and ◇ is the data group of eight groups of inputs.

Be example with electric control valve and liquid in the present embodiment, describe the computation process that is calculated parameter a and parameter b by the data group through the formula of least square method in detail, the control parameter of linear equation of the present invention adopts the method for least square method in the mathematics, owing to adopt the method for least square method can make the actual conditions output valve more near idea output, therefore the controlled parameter of least square method can reach ideal effect accurately, makes to the realistic requirement of the control procedure of control variable and enterprise demand.

Above-described embodiment has been introduced a kind of flow control methods, below two embodiment will introduce another flow control methods.

As shown in Figure 5, the invention provides a kind of flow control methods, comprising:

Step S301: obtain default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1M, or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number, namely choose data point in each interval;

At the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1M, j=1,2 wherein ... M, M are natural number; Or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number;

Liquid or gas flow X value that N is organized in the data are divided into N-1 interval, are respectively the first interval (X ₁, X ₂), the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N), be example with first interval, choose M numerical value, X in the first interval inside ₁₁, X ₁₂X _1jX _1M, M is natural number.

Perhaps, the value of N being organized the control variable Y in the data is divided into N-1 interval, is respectively the first interval (Y ₁, Y ₂), the second interval (Y ₂, Y ₃) ... k interval (Y _i, Y _I+1) ... (N-1) interval (Y _N-1, Y _N).Be example with first interval, choose M numerical value, Y in the first interval inside ₁₁, Y ₁₂Y _1jY _1M, M is natural number.

Because the liquid among the present invention or gas flow are non-linear in actual conditions, therefore in order to control the linear equation of flow more accurately, the present invention is divided into N-1 interval with liquid or gas flow X, uses each interval inner linear equation of least square method in each interval.Choose M numerical value in the first interval inside, M is natural number, both can not choose numerical value in first interval, also can choose a unlimited numerical value.Be understandable that M organizes can be in the first interval inside in the data and is evenly distributed, and also can become uneven distribution, does not do restriction at this.

Be understandable that, the precision that obtains linear equation during M=0 in first interval is lower, and along with the increase of M, the precision of linear equation can improve gradually, certainly in actual implementation procedure, be as the criterion with required precision, avoid the troublesome calculation and the implementation that adopt excessive M value to bring.

Step S302: according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number, namely obtain the data group according to data point;

Namely according to liquid in the actual conditions or the gas flow X relation with the control parameter Y of the described liquid of control or gas flow X, according to X ₁₁, X ₁₂X _1jX _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

Be example with the variable frequency pump frequency: when actual measurement, according to the reading of current transmitter and the reading X that need reach _1j(liquid or gas flow) adjusts the variable frequency pump frequency, waits for that the stable back of liquid or gas flow reading is X _1j, namely note variable frequency pump frequency Y at this moment _1j, and then obtain these group data (X, Y).

According to said method, the M group data according to obtaining increase X successively with the order that liquid or gas flow increase progressively successively in principle _1j, and according to liquid or gas flow X _1jRecord variable frequency pump frequency Y successively _1j, and then obtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), i=1,2 wherein ... M, M are natural number.

Perhaps, according to liquid in the actual conditions or the gas flow X relation with the control parameter Y of the described liquid of control or gas flow X, according to Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

Be example with the variable frequency pump frequency: when actual measurement, by variable frequency pump the variable frequency pump frequency being set is Y _1j, wait for that liquid or gas flow are stable after, read liquid or gas flow under the current variable frequency pump frequency and the reading X of record transmitter this moment by transmitter _1j, and then obtain these group data (X _1j, Y _1j).

According to said method, according to the M group data that need obtain, choose variable frequency pump frequency Y with the order of variable frequency pump frequency increments in principle _i, and according to variable frequency pump frequency Y _iRecord the reading X of transmitter successively _i, and then obtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), i=1,2 wherein ... M, M is natural number, is understandable that, the follow-up linear equation that obtains of the more big the present invention of M is closing to reality more.

Step S303: obtain and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁, namely adopt least square method calculating parameter a and parameter b;

Wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula:

Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X, Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y;

Step S304: according to described parameter a ₁With described parameter b ₁Obtain linear equation Y=a ₁X+b ₁, by being parameter a and parameter b structure linear equation;

Step S305: by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2, and namely the method for S301-S304 obtains each interval linear equation set by step;

By choosing numerical value in first interval and obtaining the method for data group, in second interval ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in choose numerical value respectively and obtain the data group, be understandable that the numerical value that can choose varying number in different intervals obtains the data group of varying number, perhaps chooses the numerical value of identical data quantity in different intervals, obtains identical data group.

Step S306: obtain required liquid or gas flow X2;

Step S307: judge the k interval that liquid or gas flow X2 are affiliated;

Because with liquid or gas flow X2, be divided into different intervals in above-mentioned steps, different interval neutral line equations are different, therefore need to judge liquid or the affiliated interval of gas flow, obtain linear equation according to the interval.

Step S308: obtain linear equation Y=a according to described k interval _kX+b _k

Have above-mentioned steps as can be known liquid or the described interval of gas flow be k, obtain the liquid of this moment or the linear equation Y=a under the gas according to the k interval _kX+b _k

Step S309: according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow, namely calculate the control parameter by linear equation.

Because the liquid among the present invention or gas flow are non-linear in actual conditions, therefore in order to control the linear equation of flow more accurately, the present invention is divided into N-1 interval with the liquid in the default N group data or gas flow X or control variable Y, and in N-1 interval, choose M data group respectively, in each interval, utilize least square method to carry out computing according to M data and obtain two parameter a and b, make up a linear equation by parameter a and b, linear relationship in namely should the interval between the flow of liquid or gas and the control parameter, represent the flow of liquid or gas and the linear equation of the linear relationship between the control parameter at N-1 the interval N-1 bar that obtains altogether, according to required liquid or the value X2 of gas flow, at first judge the interval that X2 is affiliated, and according to the flow of liquid or gas in the affiliated interval and the linear relationship between the control parameter, the value Y2 of the control parameter that acquisition is corresponding with the value X2 of the flow of liquid or gas.Present embodiment has corresponding with it linear relationship in different intervals, make the flow of linear relationship liquid or gas and the linear relationship between the control parameter tally with the actual situation more, makes the flow output of liquid or gas tally with the actual situation more.

Flow control methods is consistent with the core idea of the flow control methods of first embodiment in the present embodiment, all be that the data group formed with the flow of predefined liquid or gas and control parameter is as the basis, utilize least square method to carry out computing and obtain two parameters, obtain the flow of liquid or gas and the linear relationship between the control parameter by described two parameters.Just first kind of flow control methods obtains a linear equation according to default N group data on embodiment, the present invention obtains N-1 bar linear equation according to default N group data, compare with first kind of flow control methods, the N-1 bar linear equation that obtains in the present embodiment has reacted the flow of liquid or gas and the linear relationship between the control parameter more accurately, make flow control process more accurate, meet enterprise's requirement more.

By shown in Figure 6, the invention provides the scene embodiment of flow control methods, comprising:

Step S401: obtain 4 groups of data groups under the actual conditions.

Adopt the mode of open loop control to take liquid under the actual conditions or the value Y of gas flow X and control variable, present embodiment is example with electric control valve and liquid, in principle, tests with the order that the valve position opening degree increases progressively, and obtains 4 groups of data (X then _i, Y _i), as (1.1,1.5), (2.2,3.5), (3.3,4.2) and (4.4,5.0).Be example with liquid or gas flow X: the middle X value by the data group is divided into three intervals with liquid or gas flow X: first intervally is (1.1,2.2), and second interval is (2.2,3.3), and the 3rd interval is (3.3,4.4).

Step S402: in each interval, choose the data group.

Present embodiment is with at the first interval (X ₁, X ₂) in choose 2 numerical value: X ₁₁, X ₁₂X _1jX _1MBe example, according to liquid in the actual conditions or the gas flow X relation with the control parameter Y of the described liquid of control or gas flow X, according to X ₁₁, X ₁₂X _1jX _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

Present embodiment is example with M=2, chooses two data groups in each interval.For example between (1.1,1.5), (2.2,3.5) these two data groups, choose two data groups (1.4,1.9), (1.8,2.5); Between (2.2,3.5), (3.3,4.2) these two data groups, get two data groups (2.6,3.8), (3.0 again, 4.0), in (3.3,4.2), (4.4,5.0) get two data groups (3.6,4.5), (4.0,4.7) again between these two data groups.

Step S403: calculate each interval inner linear equation.

Be example with first interval:

1. calculated the mean value of liquid or gas flow X by 4 groups of data (1.1,1.5), (1.4,1.9), (1.8,2.5) and (2.2,3.5)

$\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i=\underset{i=1}{\overset{4}{\mathrm{\&Sigma;}}}(1.1+1.4+1.8+2.2)==6.5\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(1\right)\&CenterDot;$

$\stackrel{\&OverBar;}{X}=\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i/N=\underset{i=1}{\overset{4}{\mathrm{\&Sigma;}}}(1.1+1.4+1.8+2.2)/4=1.652\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(2\right)$

2. foundation Calculate the mean value of control parameter Y

$\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{Y}_i=\underset{i=1}{\overset{4}{\mathrm{\&Sigma;}}}(1.5+1.9+2.5+3.5)=9.4\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(3\right)$

$\stackrel{\&OverBar;}{Y}=\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{Y}_i/M+2=\underset{i=1}{\overset{4}{\mathrm{\&Sigma;}}}(1.5+1.9+2.5+3.5)/4=2.35\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(4\right)$

3. calculate $\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i{Y}_i,$ $\underset{i=0}{\overset{M+2}{\mathrm{\&Sigma;}}}{{\mathrm{<figure-callout\; id="2"\; label="X\; i"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_i}^2$

$\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i{Y}_i=\underset{i=1}{\overset{4}{\mathrm{\&Sigma;}}}(X_1{\mathrm{<figure-callout\; id="1"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_1+X_2{\mathrm{<figure-callout\; id="2"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_2+X_3{\mathrm{<figure-callout\; id="3"\; label="Y"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">Y</figure-callout>}}_3+X_4{Y}_4)$

$=1.1\&times;1.5+1.4\&times;1.9+1.8\&times;2.5+2.2\&times;3.5=16.51\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(5\right)$

$\underset{i=0}{\overset{M+2}{\mathrm{\&Sigma;}}}{{\mathrm{<figure-callout\; id="2"\; label="X\; i"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_i}^2=\underset{i=1}{\overset{8}{\mathrm{\&Sigma;}}}({{\mathrm{<figure-callout\; id="1"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_1}^2+{{\mathrm{<figure-callout\; id="2"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_2}^2+{{\mathrm{<figure-callout\; id="3"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_3}^2+{{\mathrm{<figure-callout\; id="4"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_4}^2+{{\mathrm{<figure-callout\; id="5"\; label="X"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">X</figure-callout>}}_5}^2+{{\mathrm{<figure-callout\; id="6"\; label="X"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">X</figure-callout>}}_6}^2+{{\mathrm{<figure-callout\; id="7"\; label="X"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">X</figure-callout>}}_7}^2+{{\mathrm{<figure-callout\; id="8"\; label="X"\; filenames="HDA00003040117800021.png"\; state="\{\{state\}\}">X</figure-callout>}}_8}^2)$

$=1.1\&times;1.1+1.4\&times;1.4+1.8\&times;1.8+2.2\&times;2.2=11.25\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\&CenterDot;\left(6\right)$

4. with in formula (1) (2) (3) (4) (5) and (6) the substitution formula calculating parameter a1 formula

$a1=\frac{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}}=1.796$

5. calculating parameter b1 is with formula (1) (2) and parameter a1, in the substitution formula

$\mathrm{<figure-callout\; id="1"\; label="b"\; filenames="HDA00003040117800021.png,HDA00003040117800032.png"\; state="\{\{state\}\}">b</figure-callout>}1=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=-0.569$

Obtain the linear equation Y=1.796X-0.569 that parameter a1 and parameter b 1 make up first interval.

Calculate second interval respectively by above-mentioned steps, the linear equation in the 3rd interval is:

Y=0.622X2.149。Y=0.698X-1.929。

As shown in Figure 7, the linear equation that adopts software emulation to obtain for present embodiment.

Step S404: according to required liquid or the controlled variable of gas flow X2.

Suppose that required flow is X=2.0, then judge that according to this flow X=2.0 flow is in first interval, linear equation Y=1.796X-0.569 in interval according to first, Y=3.023 will be got in the X=2.0 substitution linear equation, this moment, the value of control variable Y was the value of valve positioner or variable frequency pump frequency, and the value that adopts the duty control valve level controller of control variable Y and variable frequency pump to make it to reach Y this moment gets final product.

Because with liquid or gas flow X2, be divided into different intervals in above-mentioned steps, different interval neutral line equations are different, therefore need to judge liquid or the affiliated interval of gas flow, obtain linear equation according to the interval.

Step S406: obtain linear equation Y=a according to described k interval _kX+b _k

Have above-mentioned steps as can be known liquid or the described interval of gas flow be k, obtain the liquid of this moment or the linear equation Y=a under the gas according to the k interval _kX+b _k

Step S407: according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow., namely calculate the control parameter by linear equation.

Present embodiment describes in detail between dividing regions and choose data in the interval, and the process that is obtained linear equation by data, by the interval under judgement liquid or the gas flow, obtain according to the interval this moment flow the linear equation that should use, it is more accurate to the control of control variable to make, the closing to reality situation reaches ideal effect more.The present invention can liquid with precise control or gas flow, realize stable, in real time, flow control reliably, meet the expection of technological requirement and enterprise.

As shown in Figure 8, the invention provides a kind of volume control device, comprising:

Parameter calculation unit 100 is used for obtaining default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation, wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2, and wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=0}{\overset{N}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X, Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

The first equation acquiring unit 200 is used for making up linear equation Y=aX+b by described parameter a and described parameter b;

First acquiring unit 300 is used for obtaining required liquid or gas flow X1, according to described linear equation Y=aX+b, obtains the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow.

As shown in Figure 9, the invention provides a kind of volume control device, comprising:

Choose unit 400, be used for obtaining default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1MX _1M, or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number;

Second acquisition unit 500 is used for according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

The second equation acquiring unit 600 is used for obtaining and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁, wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}}=,$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y, according to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁, by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Third party's journey acquiring unit 700 is used for obtaining required liquid or gas flow X2, judges the k interval that liquid or gas flow X2 are affiliated, obtains linear equation Y=a according to described k interval _kX+b _k

The 3rd acquiring unit 800 is used for according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow.。

As shown in figure 10, the invention provides a kind of flow control system, comprising:

First processor 900 is used for obtaining default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation, wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2, and wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

First controller 1000, be used for making up linear equation Y=aX+b by described parameter a and described parameter b, obtain required liquid or gas flow X1, according to described linear equation Y=aX+b, obtain the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow;

First equipment 1100 to be controlled is used for linking to each other with described first controller, receives the control parameter Y1 of described liquid or gas flow, and carries out corresponding operating according to described control parameter Y1.

Described first processor or described second processor are operation Matlab process computer.

Described first controller or described second controller comprise: programmable logic controller (PLC) PLC.

Described first equipment to be controlled or described second equipment to be controlled comprise: variable frequency pump or valve positioner.

In actual conditions, first processor and first controller can have annexation also not have annexation, first processor can calculated off-line parameter a and parameter b, first controller only need use this parameter a and parameter b to get final product when artificial programming, perhaps first processor and first controller are by annexation, transfer to first controller directly with first processor calculating parameter a and parameter b, and with calculating parameter a and the parameter b that obtains, be further processed according to parameter by controller.

As shown in figure 11, the invention provides a kind of flow control system, comprising:

Second processor 1200 is used for obtaining default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1MOr at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M is natural number, according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number, obtain and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁, wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein, Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y, according to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁, by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Second controller 1300 is used for obtaining required liquid or gas flow X2, judges the k interval that liquid or gas flow X2 are affiliated, obtains linear equation Y=a according to described k interval _kX+b _k, according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow;

Second equipment 1400 to be controlled is used for linking to each other with described second controller, receives the control parameter Y2 of described liquid or gas flow, and carries out corresponding operating according to described control parameter Y2.

Described first processor or described second processor are operation Matlab process computer.

Described first controller or described second controller comprise: programmable logic controller (PLC) PLC.

Described first equipment to be controlled or described second equipment to be controlled comprise: variable frequency pump or valve positioner.

If the described function of present embodiment method realizes with the form of SFU software functional unit and during as independently production marketing or use, can be stored in the computing equipment read/write memory medium.Based on such understanding, the part that the embodiment of the invention contributes to prior art or the part of this technical scheme can embody with the form of software product, this software product is stored in the storage medium, comprise that some instructions are with so that a computing equipment (can be personal computer, server, mobile computing device or the network equipment etc.) carry out all or part of step of the described method of each embodiment of the present invention.And aforesaid storage medium comprises: various media that can be program code stored such as USB flash disk, portable hard drive, ROM (read-only memory) (ROM, Read-Only Memory), random access memory (RXM, Random Xccess Memory), magnetic disc or CD.

Each embodiment adopts the mode of going forward one by one to describe in this instructions, and what each embodiment stressed is and the difference of other embodiment that same or similar part is mutually referring to getting final product between each embodiment.

To the above-mentioned explanation of the disclosed embodiments, make this area professional and technical personnel can realize or use the present invention.Multiple modification to these embodiment will be apparent concerning those skilled in the art, and defined General Principle can realize under the situation that does not break away from the spirit or scope of the present invention in other embodiments herein.Therefore, the present invention will can not be restricted to these embodiment shown in this article, but will meet the wideest scope consistent with principle disclosed herein and features of novelty.

Claims (9)

1. a flow control methods is characterized in that, comprising:

Obtain default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation;

Wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2;

Wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula:

Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

Make up linear equation Y=aX+b by described parameter a and described parameter b;

Obtain required liquid or gas flow X1;

According to described linear equation Y=aX+b, obtain the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow.

2. a flow control methods is characterized in that, comprising:

Obtain default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1M, or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number;

According to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

Obtain and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁

Wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula: Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y;

According to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁

By the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Obtain required liquid or gas flow X2;

Judge the k interval that liquid or gas flow X2 are affiliated;

Obtain linear equation Y=a according to described k interval _kX+b _k

According to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow.

3. a volume control device is characterized in that, comprising:

Parameter calculation unit is used for obtaining default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation, wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2, and wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X, Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

The first equation acquiring unit is used for making up linear equation Y=aX+b by described parameter a and described parameter b;

First acquiring unit is used for obtaining required liquid or gas flow X1, according to described linear equation Y=aX+b, obtains the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow.

4. a volume control device is characterized in that, comprising:

Choose the unit, be used for obtaining default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1MX _1M, or at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M are natural number;

Second acquisition unit is used for according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number;

The second equation acquiring unit is used for obtaining and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁, wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{M+2}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y, according to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁, by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Third party's journey acquiring unit is used for obtaining required liquid or gas flow X2, judges the k interval that liquid or gas flow X2 are affiliated, obtains linear equation Y=a according to described k interval _kX+b _k

The 3rd acquiring unit is used for according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow.

5. a flow control system is characterized in that, comprising:

First processor is used for obtaining default N group data (X according to least square method ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) parameter a and the parameter b of corresponding linear equation, wherein, described default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in X be liquid or gas flow, Y is the control parameter of control described liquid or gas flow X, wherein i=1,2 ... N, N are natural number and N 〉=2, and wherein, the computing formula of parameter a is described in the least square method formula: $a=\frac{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i{Y}_i\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{Y}}{\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X_i}^2\right)-\left(\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}{X}_i\right)\stackrel{\&OverBar;}{X}},$ The computing formula of parameter b is described in the least square method formula: $b=\stackrel{\&OverBar;}{Y}-a\stackrel{\&OverBar;}{X}=,$ Wherein,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) in the mean value of liquid or gas flow X,

Be N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N) the middle mean value of controlling parameter Y;

First controller, be used for making up linear equation Y=aX+b by described parameter a and described parameter b, obtain required liquid or gas flow X1, according to described linear equation Y=aX+b, obtain the described liquid corresponding with described liquid or gas flow X1 or the control parameter Y1 of gas flow;

First equipment to be controlled is used for linking to each other with described first controller, receives the control parameter Y1 of described liquid or gas flow, and carries out corresponding operating according to described control parameter Y1.

6. a flow control system is characterized in that, comprising:

Second processor is used for obtaining default N group data (X ₁, Y ₁), (X ₂, Y ₂) ... (X _i, Y _i) ... (X _N, Y _N), at the first interval (X ₁, X ₂) in choose M numerical value: X ₁₁, X ₁₂X _1jX _1MOr at the first interval (Y ₁, Y ₂) in choose M numerical value: Y ₁₁, Y ₁₂Y _1jY _1M, j=1,2 wherein ... M, M is natural number, according to X ₁₁, X ₁₂X _1jX _1MOr Y ₁₁, Y ₁₂Y _1jY _1MObtain M group data (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1j, Y _1j) ... (X _1M, Y _1M), j=1,2 wherein ... M, M are natural number, obtain and M+2 group data (X according to the least square method formula ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) the parameter a of corresponding linear equation ₁And parameter b ₁, wherein, the computing formula of parameter a is described in the least square method formula:

The computing formula of parameter b is described in the least square method formula:

Wherein,

Be M+2 group data group (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) in the mean value of liquid or gas flow X,

Be M+2 group data (X ₁, Y ₁), (X ₁₁, Y ₁₁), (X ₁₂, Y ₁₂) ... (X _1i, Y _1i) ... (X _1M, Y _1M), (X ₂, Y ₂) mean value of control parameter Y, according to described parameter a ₁With described parameter b ₁Make up linear equation Y=a ₁X+b ₁, by the method for in first interval, obtaining linear equation, respectively at the second interval (X ₂, X ₃) ... k interval (X _i, X _I+1) ... (N-1) interval (X _N-1, X _N) in obtain linear equation Y=a ₂X+b ₂Y=a _kX+b _kY=a _N-1X+b _N-1, k=1,2 wherein ... (N-1), N is natural number and N 〉=2;

Second controller is used for obtaining required liquid or gas flow X2, judges the k interval that liquid or gas flow X2 are affiliated, obtains linear equation Y=a according to described k interval _kX+b _k, according to described linear equation Y=a _kX+b _k, obtain the described liquid corresponding with described liquid or gas flow X2 or the control parameter Y2 of gas flow;

Second equipment to be controlled is used for linking to each other with described second controller, receives the control parameter Y2 of described liquid or gas flow, and carries out corresponding operating according to described control parameter Y2.

7. as claim 5 or 6 described systems, it is characterized in that described first processor or described second processor are:

The computing machine of operation Matlab program.

8. as claim 5 or 6 described systems, it is characterized in that described first controller or described second controller comprise:

Programmable logic controller (PLC) PLC.

9. as claim 5 or 6 described systems, it is characterized in that described first equipment to be controlled or described second equipment to be controlled comprise:

Variable frequency pump or valve positioner.

Images