CN102608911B - Fossil power plant coordination control method based on multi-parameter prediction - Google Patents

Abstract

The invention discloses a fossil power plant coordination control method based on multi-parameter prediction. Aiming at the characteristics that a boiler controlled object is lagged, slow in response process and the like, feedwater flow, coal supply quantity and steam turbine valve opening are estimated reasonably, deviation of main steam pressure and separator outlet temperature is predicted, and a main steam pressure control loop and a separator outlet temperature control loop are respectively formed, and are coordinated with a load control loop so as to form a fossil power plant coordination control system. Control quality of the fossil power plant coordination control system is effectively improved, main steam pressure fluctuation during load change is suppressed effectively while the load change is responded fast, deviation between main steam pressure and a setting value is reduced, the separator outlet temperature fluctuation is suppressed, and the situation that the separator outlet temperature is over high is reduced. Besides, the stability of a boiler control system and the operation efficiency of a unit are improved.

Description

A kind of fired power generating unit control method for coordinating based on multi-parameter prediction

Technical field

The present invention is a kind of control strategy combining based on Model Predictive Control and multi-parameter prediction, thermal power unit boiler main vapour pressure and separator outlet temperature are regulated, make main vapour pressure and separator outlet temperature fast, a kind of control method of stable, agonic tracking setting value.

Background technology

At present, the configuration logic that the coordination control strategy of domestic fired power generating unit mainly adopts external all big enterprises to provide, adopt the regulation scheme of load instruction feedforward and proportion integration differentiation feedback, its core thinking is: as much as possible whole control system setting is become to the mode of adjusted open loop, feedback regulation only plays regulating action by a small margin.This scheme requires the parameter in feedforward control loop must adjust very accurately, stable for coal, unit equipment stable, the external unit of unit operation mode maturation, this scheme is more effective, therefore the suggested design of Dou Shi foreign vendor all the time; But, unit control changeable for coal and measuring equipment out of true, operational factor often and design parameter there is the domestic unit of relatively large deviation, controlling effect can obvious variation.By the investigation to on-the-spot ruuning situation and conclusion, fortune unit Harmonic Control be mainly reflected in following several aspect

1, eliminate disturbance ability, be prone to parameter fluctuation and regulate vibration situation

This is situation about the most generally occurring in current unit operation; unit at significantly varying load, start and stop pulverized coal preparation system, blow under the disturbance operating modes such as ash; control system often there will be controls the situation that unstable or temperature, pressure significantly depart from setting value, has a strong impact on safety in operation.

2, unit load elevation rate is low

Conventional AGC control program, due to large time delay controlled device cannot be found to effective control method, the ascending, descending speed of unit load is only in 1%/min left and right, and peak regulation, the fm capacity of unit are poor, cannot meet the response requirement of electrical network to unit load.

3, coal type change is large on control system impact

In the time of coal-fired quality variation, control system lacks self-adaptation means, also variation thereupon of control performance.Operations staff, for ensureing unit safety, can only adopt very low varying load rate operation.

4, the fluctuation of the controlled quentity controlled variable such as fuel, feedwater is large

Frequently repeatedly changing of load instruction, make the also significantly fluctuation back and forth of each controlled quentity controlled variable such as fuel, feedwater, air-supply of unit, although now the controlled parameter such as main vapour pressure, temperature is comparatively stable, but can cause the variation repeatedly of boiler water wall and superheater tubes thermal stress, easily cause oxide skin to come off, greatly increased the possibility of boiler booster.

Summary of the invention

Technical matters: the object of this invention is to provide a kind of fired power generating unit control method for coordinating based on multi-parameter prediction, for promoting peak regulation, the fm capacity of unit, reduce the fluctuating range of each controlled quentity controlled variable such as coal-supplying amount, feedwater flow, the thermal stress that reduces boiler water wall and superheater tubes changes, and reduces that oxide skin comes off and the problem such as the possibility of boiler booster.

Technical scheme: the present invention is the problems referred to above that overcome fired power generating unit coordinated control system, make up the deficiency of traditional control program, by the strategy that adopts PREDICTIVE CONTROL and multi-parameter prediction to combine, reduce coal-supplying amount, feedwater flow fluctuation, accelerate main vapour pressure and separator outlet temperature-responsive speed, increase coordinated control system stability.

The invention is characterized in that the method comprises following two control loops: main vapour pressure control loop, separator outlet temperature control loop; Wherein main vapour pressure control loop comprises following structure: keep fallout predictor, linear incremental fallout predictor, main vapour pressure model, main vapour pressure controller; Separator outlet temperature control loop comprises following structure: keep fallout predictor, linear incremental fallout predictor, separator outlet temperature model, separator outlet temperature controller;

Linear incremental fallout predictor is to ask for output by the mode of increment linear decrease, as the current u that is input as of this fallout predictor _z(k), time, linear incremental fallout predictor is output as Y _z(k)=[y _z(k+1) y _z(k+2) ... y _z(k+N)], wherein $y_z(k+j)=\frac{1-{\mathrm{\β}}^{j+1}}{1-\mathrm{\β}}[u_z\left(k\right)-u_z(k-1)]+u_z\left(k\right)$ J=1,2,3...N, β is decline factor, and N is Prediction Parameters time span, and k is current time, and z is the code name of incremental forecasting device;

Keep fallout predictor using current this fallout predictor input as its output, work as the current u that is input as of this fallout predictor _b(k), time, keep fallout predictor to be output as Y _b(k)=[u _b(k) u _b(k) ... u _b(k)] _{1 × N}, N is Prediction Parameters time span, b is the code name that keeps fallout predictor;

On above architecture basics, the fired power generating unit control method for coordinating based on multi-parameter prediction comprises the steps:

1). respectively taking feedwater flow Fw, coal-supplying amount Fu, steam turbine valve opening Tm as step amount, obtain the step response value of main vapour pressure Msp, separator outlet temperature T sp, load Ne, and be recorded in historical data base;

2). by least square using identification method, the data in historical data base are carried out to matching, obtain following transport function: taking Fw as input, Msp as output feedwater-main vapour pressure transport function taking Fu as input, Msp as output coal supply-main vapour pressure transport function taking Tm as input, Msp as output steam turbine valve-main vapour pressure transport function taking Fw as input, Ne as output feedwater-load transport function taking Fu as input, Ne as output coal supply-load transport function taking Tm as input, Ne as output steam turbine valve-load transport function taking Fw as input, Tsp as output feedwater-separator outlet temperature transport function taking Fu as input, Tsp as output coal supply-separator outlet temperature transport function taking Tm as input, Tsp as output steam turbine valve-separator outlet temperature transport function

3). right carry out bilinearity discretize and obtain discretize transport function wherein for feedwater-main vapour pressure discrete molecules polynomial expression, for the discrete denominator polynomial expression of feedwater-main vapour pressure, q is lead factor;

4). structure Diophantine equation: $1=E_N^{\mathrm{msp}}\left(q^{-1}\right)A_{\mathrm{fw}}^{\mathrm{msp}}\left(q^{-1}\right)\mathrm{\Δ}+q^{-N}{F}_N^{\mathrm{msp}}\left(q^{-1}\right),$ Must feed water-main vapour pressure separates the first polynomial expression separate the second polynomial expression with feedwater-main vapour pressure

5). order $G^{\mathrm{msp}}\left(q^{-1}\right)=E_N^{\mathrm{msp}}\left(q^{-1}\right)B_{\mathrm{fw}}^{\mathrm{msp}}\left(q^{-1}\right)=\underset{i=0}{\overset{N+N_{\mathrm{bfw}}}{\mathrm{\Σ}}}{g}_i^{\mathrm{msp}}{q}^{-i},$ Wherein G ^msp(q ^-1) be main vapour pressure forward direction polynomial expression, for main vapour pressure forward direction multinomial coefficient, N _bfwfor feedwater-main vapour pressure discrete molecules polynomial expression order;

6). structure main vapour pressure control coefrficient ${\mathrm{\α}}^{\mathrm{msp}}={[\underset{i=0}{\overset{i=N-1}{\mathrm{\Σ}}}{\left(g_i^{\mathrm{msp}}\right)}^2+{\mathrm{\γ}}^{\mathrm{msp}}]}^{-1},$ Wherein γ ^mspfor main vapour pressure controlled quentity controlled variable affects component coefficient;

7). making current is the k moment, current coal-supplying amount Fu (k), steam turbine valve opening Tm (k) are through linear incremental fallout predictor, feedwater flow Fw (k) after keeping fallout predictor to calculate, and following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value are:

Fw(k+j)＝Fw(k-1)j＝1，2，3...N

$\mathrm{Fu}(k+j)=\frac{1-{{\mathrm{\β}}_{\mathrm{fu}}}^{j+2}}{1-{\mathrm{\β}}_{\mathrm{fu}}}\mathrm{\ΔFu}(k-1)+\mathrm{Fu}(k-1)$ j＝1，2，3...N

j=1,2,3...N, wherein β _fuand β _tmbe respectively coal supply controlled quentity controlled variable attenuation coefficient and steam turbine valve opening attenuation coefficient and be and be less than 1 constant that is greater than 0;

8). according to following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value and corresponding transport function with calculate following main vapour pressure predicted value Msp through main vapour pressure model _t(k+j) j=1,2,3...N;

9). getting main vapour pressure setting value is Msp _rthrough maintenance fallout predictor calculate after poor with following main vapour pressure predicted value, and by main vapour pressure controller calculate main vapour pressure control loop feed water controlled quentity controlled variable be

${\mathrm{Fw}}_c={\mathrm{\α}}^{\mathrm{msp}}\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}[{\mathrm{Msp}}_r-{\mathrm{Msp}}_t(k+i)]g_i^{\mathrm{msp}};$

10). by Fw _cas the desired value of feedwater flow, be sent in feed pump topworks, by changing feedwater flow control main vapour pressure;

A) feedwater flow increases, and coal-supplying amount is constant, and boiler overheating section reduces, and main vapour pressure reduces;

B) feedwater flow reduces, and coal-supplying amount is constant, and boiler overheating section increases, and main vapour pressure increases;

Thereby control main vapour pressure of boiler;

11). right carry out bilinearity discretize and obtain discretize transport function wherein for coal supply-separator outlet temperature discrete molecules polynomial expression, for the discrete denominator polynomial expression of coal supply-separator temperature;

12). structure Diophantine equation, $1=E_N^{\mathrm{tsp}}\left(q^{-1}\right)A_{\mathrm{fu}}^{\mathrm{tsp}}\left(q^{-1}\right)\mathrm{\Δ}+q^{-N}{F}_N^{\mathrm{tsp}}\left(q^{-1}\right),$ Obtain coal supply-separator outlet temperature and separate the first polynomial expression separate the second polynomial expression with coal supply-separator outlet temperature

$F_N^{\mathrm{tsp}}\left(q^{-1}\right);$

13). order $G^{\mathrm{tsp}}\left(q^{-1}\right)=E_N^{\mathrm{tsp}}\left(q^{-1}\right)B_{\mathrm{fu}}^{\mathrm{tsp}}\left(q^{-1}\right)=\underset{i=0}{\overset{N+N_{\mathrm{bfu}}}{\mathrm{\Σ}}}{g}_i^{\mathrm{tsp}}{q}^{-i},$ Wherein G ^tsp(q ^-1) be separator outlet temperature forward direction polynomial expression, for separator outlet temperature forward direction multinomial coefficient, N _bfufor coal supply-separator outlet temperature discrete molecules polynomial expression order;

14). structure separator outlet temperature control coefrficient wherein γ ^tspfor separator outlet temperature controlled quentity controlled variable affects component coefficient;

15). making current is the k moment, current feedwater flow is that Fw (k), steam turbine valve opening are Tm (k) through linear incremental fallout predictor, coal-supplying amount Fu (k) after keeping fallout predictor to calculate, and obtains following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value to be

Fu(k+j)＝Fu(k-1)j＝1，2，3...N

$\mathrm{Fw}(k+j)=\frac{1-{{\mathrm{\β}}_{\mathrm{fw}}}^{j+2}}{1-{\mathrm{\β}}_{\mathrm{fw}}}\mathrm{\ΔFw}(k-1)+\mathrm{Fw}(k-1)$ j＝1，2，3...N

j=1,2,3...N, wherein β _fwfor feedwater controlled quentity controlled variable attenuation coefficient, and for being less than 1 constant that is greater than 0.

16). according to following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value and corresponding transport function with calculate through separator outlet temperature model, obtain following separator outlet temperature prediction value Tsp _t(k+j) j=1,2,3...N;

17). getting separator outlet desired temperature is Tsp _r, poor with following separator outlet temperature prediction value after keeping fallout predictor to calculate, and calculate coal supply controlled quentity controlled variable by separator outlet temperature controller and be

${\mathrm{Fu}}_c={\mathrm{\α}}^{\mathrm{tsp}}\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}[{\mathrm{Tsp}}_r-{\mathrm{Tsp}}_t(k+i)]g_i^{\mathrm{tsp}};$

18). by Fu _cas the desired value of coal-supplying amount, be sent in feeder topworks, by changing Limestone control separator outlet temperature;

A) feeder rise of rotational speed, coal-supplying amount increases, and boiler overheating section increases, and superheated vapor outlet temperature rises, separator outlet temperature rise;

B) feeder rotating speed declines, and coal-supplying amount reduces, and boiler overheating section reduces, and superheated vapor outlet temperature declines, and separator outlet temperature declines; Thereby control boiler separator outlet temperature.

Beneficial effect: by the strategy that adopts PREDICTIVE CONTROL and multi-parameter prediction to combine, reduce coal-supplying amount, feedwater flow fluctuation, the thermal stress that reduces boiler water wall and superheater tubes changes, reduces that oxide skin comes off and the problem such as the possibility of boiler booster.Accelerate main vapour pressure and separator outlet temperature-responsive speed, increase coordinated control system stability.

Brief description of the drawings

Fig. 1 is control structure figure of the present invention.

Embodiment

Specific implementation process of the present invention is as follows:

1,, by fired power generating unit is carried out to site test, obtain following data: discharge Fw, coal-supplying amount Fu, steam turbine valve opening Tm, main vapour pressure Msp, separator outlet temperature T sp, load Ne.

2,, according to the data identification mathematical model of obtaining, adopt transfer function model, the transport function that identification is corresponding:

Wherein $G_{\mathrm{fu}}^{\mathrm{ne}}=\frac{2.2093}{(1+400s)(1+800s)},$ $G_{\mathrm{fw}}^{\mathrm{ne}}=\frac{0.36741}{{(1+90s)}^2}-\frac{0.36741}{4000s+1},$ $G_{\mathrm{tm}}^{\mathrm{msp}}=\frac{-0.335}{1+95s},$

$G_{\mathrm{tm}}^{\mathrm{tsp}}=\frac{-1.54916}{(1+30s)(1+90s)}{e}^{-90s},$ $G_{\mathrm{fu}}^{\mathrm{msp}}=\frac{0.0560166}{(1+200s)(1+600s)},$ $G_{\mathrm{fu}}^{\mathrm{tsp}}=\frac{0.738589}{(1+300s)(1+450s)},$

$G_{\mathrm{fw}}^{\mathrm{msp}}=\frac{0.018159}{(1+50s)(1+100s)}-\frac{0.01}{1+600s},$ $G_{\mathrm{fw}}^{\mathrm{tsp}}=0,G_{\mathrm{tm}}^{\mathrm{ne}}=\frac{5.125}{1+10s}-\frac{5.125}{(1+80s)(1+120s)};$

3, right carry out bilinearity discretize and obtain discretize transport function

$\frac{B_{\mathrm{fw}}^{\mathrm{msp}}\left(q^{-1}\right)}{A_{\mathrm{fw}}^{\mathrm{msp}}\left(q^{-1}\right)}=\frac{-4.034\×{10}^{-6}+1.397\×{10}^{-4}{q}^{-1}+5.202\×{10}^{-6}{q}^{-2}-1.385\×{10}^{-4}{q}^{-3}}{1-2.7q^{-1}+2.4347q^{-2}-0.728q^{-3}};$

4, get N=10, separate Diophantine equation, $1=E_{10}^{\mathrm{msp}}\left(q^{-1}\right)A_{\mathrm{fw}}^{\mathrm{msp}}\left(q^{-1}\right)\mathrm{\Δ}+q^{-10}{F}_{10}^{\mathrm{msp}}\left(q^{-1}\right),$

$E_{10}^{\mathrm{msp}}\left(q^{-1}\right)=1+3.7064q^{-1}+8.5964q^{-2}+15.9693q^{-3}+25.988q^{-4}$

$+38.712q^{-5}+54.1229q^{-6}+72.146q^{-7}+92.666q^{-8}+115.54q^{-9};$

5、 $G_{\mathrm{msp}}\left(q^{-1}\right)=E_N^{\mathrm{msp}}\left(q^{-1}\right)B_{\mathrm{fu}}^{\mathrm{msp}}\left(q^{-1}\right)=\underset{i=0}{\mathrm{\Σ}}{g}_i^{\mathrm{msp}}{q}^{-i},$ $g_0^{\mathrm{msp}}=-4.0342\×{10}^{-6},$

$g_1^{\mathrm{msp}}=1.247\×{10}^{-4},$ $g_2^{\mathrm{msp}}=4.8815\×{10}^{-4},$ $g_3^{\mathrm{msp}}=0.001,$ $g_4^{\mathrm{msp}}=0.0017,$

$g_5^{\mathrm{msp}}=0.0024,$ $g_6^{\mathrm{msp}}=0.0031,$ $g_7^{\mathrm{msp}}=0.0039,$ $g_8^{\mathrm{msp}}=0.0046,$ $g_9^{\mathrm{msp}}=0.0054;$

6, get γ ^msp=0.1, main vapour pressure control coefrficient α ^msp=9.99;

7, making current is the k moment, gets β _fu=0.1 and β _tm=0.1, current feedwater flow Fw (k) and steam turbine valve opening Tm (k) are Fu (k) after keeping fallout predictor through linear incremental fallout predictor, coal-supplying amount, obtain following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value to be

Fw(k+j)＝Fw(k-1)j＝0，2，3...9

$\mathrm{Fu}(k+j)=\frac{1-{0.1}^{j+2}}{0.9}\mathrm{\ΔFu}(k-1)+\mathrm{Fu}(k-1)$ j＝0，2，3...9

$\mathrm{Tm}(k+j)=\frac{1-{0.1}^{j+1}}{0.9}\mathrm{\ΔTm}\left(k\right)+\mathrm{Tm}\left(k\right)$ j＝0，2，3...9，；

8, according to following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value and corresponding transport function with calculate following main vapour pressure predicted value sequence through main vapour pressure model

Msp _t(k+j)j＝1，2，3...10；

9, getting main vapour pressure setting value is Msp _rpoor with following main vapour pressure predicted value after keeping fallout predictor to calculate, and calculate controlled quentity controlled variable by main vapour pressure controller

10, by Fw _cas the desired value of feedwater flow, be sent in feed pump topworks, by changing feedwater flow control main vapour pressure;

A) feedwater flow increases, and coal-supplying amount is constant, and boiler overheating section reduces, and main vapour pressure reduces;

B) feedwater flow reduces, and coal-supplying amount is constant, and boiler overheating section increases, and main vapour pressure increases; Thereby control main vapour pressure of boiler;

11, right carry out bilinearity discretize and obtain discretize transport function

$\frac{B_{\mathrm{fu}}^{\mathrm{tsp}}\left(q^{-1}\right)}{A_{\mathrm{fu}}^{\mathrm{tsp}}\left(q^{-1}\right)}=\frac{1.331\×{10}^{-4}+2.66\×{10}^{-4}{q}^{-1}+1.331\×{10}^{-4}{q}^{-2}}{1-1.9452q^{-1}+0.946q^2};$

12, get N=10, solve Diophantine equation, $E_{10}^{\mathrm{tsp}}=1+2.9452q^{-1}+5.7832q^{-2}+9.4637q^{-3}+13.9384q^{-4}$

$+19.1312q^{-5}+25.088q^{-6}+31.6764q^{-7}+38.8858q^{-8}+46.6777q^{-9};$

13, order $G_{\mathrm{tsp}}\left(q^{-1}\right)=E_N^{\mathrm{tsp}}\left(q^{-1}\right)B_{\mathrm{fu}}^{\mathrm{tsp}}\left(q^{-1}\right)=\underset{i=0}{\mathrm{\Σ}}{g}_i^{\mathrm{tsp}}{q}^{-i},$ $g_0^{\mathrm{tsp}}=1.33\×{10}^{-4},$

$g_1^{\mathrm{tsp}}=6.58\×{10}^{-4},$ $g_2^{\mathrm{tsp}}=0.0017,$ $g_3^{\mathrm{tsp}}=0.0032,$ $g_4^{\mathrm{tsp}}=0.0051,$ $g_5^{\mathrm{tsp}}=0.0075,$

$g_6^{\mathrm{tsp}}=0.0103,$ $g_7^{\mathrm{tsp}}=0.0134,$ $g_8^{\mathrm{tsp}}=0.0169,$ $g_9^{\mathrm{tsp}}=0.0208;$

14, get γ ^tsp=0.1, separator outlet temperature control coefrficient α ^tsp=9.89;

15, making current is the k moment, and current feedwater flow is that Fw (k), coal-supplying amount are that Fu (k), steam turbine valve opening are Tm (k), gets β _fw=0.1 and β _tm=0.1, following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value are

Fu(k+j)＝Fu(k-1)j＝0，2，3...9

$\mathrm{Fw}(k+j)=\frac{1-{0.1}^{j+2}}{0.9}\mathrm{\ΔFw}(k-1)+\mathrm{Fw}(k-1)$ j＝0，2，3...9

$\mathrm{Tm}(k+j)=\frac{1-{0.1}^{j+1}}{0.9}\mathrm{\ΔTm}\left(k\right)+\mathrm{Tm}\left(k\right)$ j＝0，2，3...9；

16, according to following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value and corresponding transport function with calculate following separator outlet temperature prediction value Tsp _t(k+j) j=1,2,3...10;

17, getting separator outlet desired temperature is Tsp _r, poor with following separator outlet temperature prediction value after keeping fallout predictor to calculate, and calculate controlled quentity controlled variable by separator outlet temperature controller and be

${\mathrm{Fu}}_c=9.89\underset{i=0}{\overset{9}{\mathrm{\Σ}}}[{\mathrm{Tsp}}_r-{\mathrm{Tsp}}_t(k+i)]g_{9-i}^{\mathrm{tsp}};$

18, by Fu _cas the desired value of coal-supplying amount, be sent in feeder topworks, by changing Limestone control separator outlet temperature;

A) feeder rise of rotational speed, coal-supplying amount increases, and boiler overheating section increases, and superheated vapor outlet temperature rises, separator outlet temperature rise;

B) feeder rotating speed declines, and coal-supplying amount reduces, and boiler overheating section reduces, and superheated vapor outlet temperature declines, and separator outlet temperature declines; Thereby control boiler separator outlet temperature.

Claims (1)

1. the fired power generating unit control method for coordinating based on multi-parameter prediction, is characterized in that this control method comprises following two control loops: main vapour pressure control loop, separator outlet temperature control loop; Wherein main vapour pressure control loop comprises following structure: keep fallout predictor, linear incremental fallout predictor, main vapour pressure model, main vapour pressure controller; Separator outlet temperature control loop comprises following structure: keep fallout predictor, linear incremental fallout predictor, separator outlet temperature model, separator outlet temperature controller;

Linear incremental fallout predictor is to ask for output by the mode of increment linear decrease, as the current u that is input as of this fallout predictor _z(k), time, linear incremental fallout predictor is output as Y _z(k)=[y _z(k+1) y _z(k+2) ... y _z(k+N)], wherein $y_z(k+j)=\frac{1-{\mathrm{\β}}^{j+1}}{1-\mathrm{\β}}[u_z\left(k\right)-u_z(k-1)]+u_z\left(k\right)$ J=1,2,3...N, β is decline factor, and N is Prediction Parameters time span, and k is current time, and z is the code name of incremental forecasting device;

Keep fallout predictor using current this fallout predictor input as its output, work as the current u that is input as of this fallout predictor _b(k), time, keep fallout predictor to be output as Y _b(k)=[u _b(k) u _b(k) ... u _b(k)] _{1 × N}, N is Prediction Parameters time span, b is the code name that keeps fallout predictor;

On above architecture basics, the fired power generating unit control method for coordinating based on multi-parameter prediction comprises the steps:

1). respectively taking feedwater flow fw, coal-supplying amount fu, steam turbine valve opening tm as step amount, obtain the step response value of main vapour pressure msp, separator outlet temperature t sp, load ne, and be recorded in historical data base;

2). by least square using identification method, the data in historical data base are carried out to matching, obtain following transport function: taking fw as input, msp as output feedwater-main vapour pressure transport function taking fu as input, msp as output coal supply-main vapour pressure transport function taking tm as input, msp as output steam turbine valve-main vapour pressure transport function taking fw as input, ne as output feedwater-load transport function taking fu as input, ne as output coal supply-load transport function taking tm as input, ne as output steam turbine valve-load transport function taking fw as input, tsp as output feedwater-separator outlet temperature transport function taking fu as input, tsp as output coal supply-separator outlet temperature transport function taking tm as input, tsp as output steam turbine valve-separator outlet temperature transport function

3). right carry out bilinearity discretize and obtain discretize transport function wherein (q ^-1) be feedwater-main vapour pressure discrete molecules polynomial expression, (q ^-1) be the discrete denominator polynomial expression of feedwater-main vapour pressure, q is lead factor;

4). structure Diophantine equation: must feed water-main vapour pressure separates the first polynomial expression (q ^-1) separate the second polynomial expression with feedwater-main vapour pressure (q ^-1), wherein △ is difference operator;

5). order $G^{\mathrm{map}}\left(q^{-1}\right)=E_N^{\mathrm{msp}}\left(q^{-1}\right)B_{\mathrm{fw}}^{\mathrm{msp}}\left(q^{-1}\right)=\underset{i=0}{\overset{N+N_{\mathrm{bfw}}}{\mathrm{\Σ}}}{g}_i^{\mathrm{msp}}{q}^{-i},$ Wherein G ^msp(q ^-1) be main vapour pressure forward direction polynomial expression, for main vapour pressure forward direction multinomial coefficient, N _bfwfor feedwater-main vapour pressure discrete molecules polynomial expression (q ^-1) order;

6). structure main vapour pressure control coefrficient wherein γ ^mspfor main vapour pressure controlled quentity controlled variable affects component coefficient;

7). making current is the k moment, current coal-supplying amount Fu (k), steam turbine valve opening Tm (k) are through linear incremental fallout predictor, feedwater flow Fw (k) after keeping fallout predictor to calculate, and following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value are:

Fw(k+j)＝Fw(k-1) j＝1,2,3...N

$\mathrm{Fu}(k+j)=\frac{1-{{\mathrm{\β}}_{\mathrm{fu}}}^{j+2}}{1-{\mathrm{\β}}_{\mathrm{fu}}}\mathrm{\ΔFu}(k-1)+\mathrm{Fu}(k-1)$ j＝1,2,3...N

j=1,2,3...N, wherein β _fuand β _tmbe respectively coal supply controlled quentity controlled variable attenuation coefficient and steam turbine valve opening attenuation coefficient and be and be less than 1 constant that is greater than 0;

8). according to following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value and corresponding transport function with calculate following main vapour pressure predicted value Msp through main vapour pressure model _t(k+j) j=1,2,3...N;

9). getting main vapour pressure setting value is Msp _rthrough maintenance fallout predictor calculate after poor with following main vapour pressure predicted value, and by main vapour pressure controller calculate main vapour pressure control loop feed water controlled quentity controlled variable be ${\mathrm{Fw}}_c={\mathrm{\α}}^{\mathrm{msp}}\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}[{\mathrm{Msp}}_r-{\mathrm{Msp}}_t(k+i)]g_i^{\mathrm{msp}};$

10). by Fw _cas the desired value of feedwater flow, be sent in feed pump topworks, by changing feedwater flow control main vapour pressure;

A) feedwater flow increases, and coal-supplying amount is constant, and boiler overheating section reduces, and main vapour pressure reduces;

B) feedwater flow reduces, and coal-supplying amount is constant, and boiler overheating section increases, and main vapour pressure increases;

Thereby control main vapour pressure of boiler;

11). right carry out bilinearity discretize and obtain discretize transport function wherein (q ^-1) be coal supply-separator outlet temperature discrete molecules polynomial expression, (q ^-1) be the discrete denominator polynomial expression of coal supply-separator outlet temperature;

12). structure Diophantine equation, obtain coal supply-separator outlet temperature and separate the first polynomial expression (q ^-1) separate the second polynomial expression with coal supply-separator outlet temperature (q ^-1);

13). order $G^{\mathrm{tsp}}\left(q^{-1}\right)=E_N^{\mathrm{tsp}}\left(q^{-1}\right)B_{\mathrm{fu}}^{\mathrm{tsp}}\left(q^{-1}\right)=\underset{i=0}{\overset{N+N_{\mathrm{bfu}}}{\mathrm{\Σ}}}{g}_i^{\mathrm{tsp}}{q}^{-i},$ Wherein G ^tsp(q ^-1) be separator outlet temperature forward direction polynomial expression, for separator outlet temperature forward direction multinomial coefficient, N _bfufor coal supply-separator outlet temperature discrete molecules polynomial expression (q ^-1) order;

14). structure separator outlet temperature control coefrficient wherein γ ^tspfor separator outlet temperature controlled quentity controlled variable affects component coefficient;

15). making current is the k moment, current feedwater flow is that Fw (k), steam turbine valve opening are Tm (k) through linear incremental fallout predictor, coal-supplying amount Fu (k) after keeping fallout predictor to calculate, and obtains following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value to be

Fu(k+j)＝Fu(k-1) j＝1,2,3...N

$\mathrm{Fu}(k+j)=\frac{1-{{\mathrm{\β}}_{\mathrm{fu}}}^{j+2}}{1-{\mathrm{\β}}_{\mathrm{fu}}}\mathrm{\ΔFu}(k-1)+\mathrm{Fu}(k-1)$ j＝1,2,3...N

j=1,2,3...N, wherein β _fwfor feedwater controlled quentity controlled variable attenuation coefficient, and for being less than 1 constant that is greater than 0;

16). according to following feedwater flow, coal-supplying amount, steam turbine valve opening predicted value and corresponding transport function with calculate through separator outlet temperature model, obtain following separator outlet temperature prediction value Tsp _t(k+j) j=1,2,3...N;

17). getting separator outlet desired temperature is Tsp _r, poor with following separator outlet temperature prediction value after keeping fallout predictor to calculate, and calculate coal supply controlled quentity controlled variable by separator outlet temperature controller and be ${\mathrm{Fu}}_c={\mathrm{\α}}^{\mathrm{tsp}}\underset{i=0}{\overset{N-1}{\mathrm{\Σ}}}[{\mathrm{Tsp}}_r-{\mathrm{Tsp}}_t(k+i)]g_i^{\mathrm{Tsp}};$

18). by Fu _cas the desired value of coal-supplying amount, be sent in feeder topworks, by changing Limestone control separator outlet temperature;

A) feeder rise of rotational speed, coal-supplying amount increases, and boiler overheating section increases, and superheated vapor outlet temperature rises, separator outlet temperature rise;

B) feeder rotating speed declines, and coal-supplying amount reduces, and boiler overheating section reduces, and superheated vapor outlet temperature declines, and separator outlet temperature declines; Thereby control boiler separator outlet temperature.