CN102566419B - Dynamic surface control method for opening of main throttle valve of steam turbine generator - Google Patents

Abstract

The invention discloses a dynamic surface control method for the opening of a main throttle valve of a steam turbine generator. The method comprises the following steps of: 1, analyzing a main throttle valve opening control system model, and constructing; 2, performing dynamic surface control and design on the opening of the main throttle valve of the steam turbine generator; 3, inspecting tracking performance, and adjusting parameters; and 4, finishing the design. The dynamic surface control method for the opening of the main throttle valve of the steam turbine generator is provided for the main throttle valve opening control system model, so that a preset track can be quickly and accurately tracked by the power angle of the steam turbine generator of a closed-loop system on the basis of ensuring the stability of a closed-loop semi-global system. The method has high practical value and a wide application prospect in the technical field of automatic control.

Description

A kind of dynamic surface control method for opening of main throttle valve of steam turbine generator

(1) technical field

The present invention relates to a kind of dynamic surface control method for opening of main throttle valve of steam turbine generator, it is for the infinitely great bus system of unit, and a kind of dynamic surface control method for opening of main throttle valve of steam turbine generator providing, for controlling turbodynamo merit angle, belongs to automatic control technology field.

(2) background technology

The excitation of turbodynamo is controlled and porthole adjusting is two important means that improve stability of power system.In the PhD dissertation of Sun Liying " the electric system non linear robust adaptive control design based on backstepping method ", point out, because excitation is controlled the restriction that is subject to exciting current top value, and require generator to there is too high exciting current top value, will increase generator manufacturing cost; Meanwhile, the ascending velocity of exciter current of generator also will be subject to the restriction of field copper time constant.Therefore, only relying on excitation to control is limited to the improvement of system stability.Along with powerful Reheat-type turbogenerator group is applied to electric system, power-frequency electric-liquid type speed regulator replaces mechanical hydraulic-pressure type speed regulator day by day, by improving main steam valve of turbine generator, control to improve Primary frequency control ability and the load adaptability of Reheat-type turbogenerator group, thereby improve the stability of electric system, there is the meaning of particular importance.

In recent years, many advanced persons' control method is used in the design of main steam valve of turbine generator control, comprising feedback linearization method, method for optimally controlling etc.The people such as Li Wenlei (are referred to < < control theories in 2003 and apply > 20 3 phases of volume of >) and pointing out in " main steam valve of turbine generator nonlinear robust control " literary composition, these methods do not possess the robustness to parameter and model variation, and helpless to non-matching uncertainty in system.Although counter, push away and control the non-matching uncertain problem of design energy resolution system, but have " differential blast " phenomenon.Dynamic surface control method is a kind of control method of novelty, and its design procedure is clear, and design process is simple, and the nonlinear system of lower triangular form is had to good control effect.This control method is introduced a low-pass first order filter in each step design, makes the basic decoupling zero of design of each step design of control law and previous stage, thereby the complexity of control law is declined greatly, has fundamentally eliminated " differential blast " phenomenon.

Under this technical background, the present invention is directed to the infinitely great bus system of unit, provide a kind of dynamic surface control method for opening of main throttle valve of steam turbine generator, for controlling turbodynamo merit angle.Adopt this control not only to guarantee the stability of closed-loop system, also realized the fast and accurately tracking of turbodynamo merit angle to desired trajectory.

(3) summary of the invention

1, goal of the invention

The object of the invention is: for main steam valve control system model, overcome the deficiency of existing control technology, and provide a kind of dynamic surface control method for opening of main throttle valve of steam turbine generator, it is guaranteeing, on the basis that closed loop half global system is stable, to realize the fast and accurately tracking of closed-loop system turbodynamo merit angle to desired trajectory.

The present invention is a kind of dynamic surface control method for opening of main throttle valve of steam turbine generator, its design philosophy is: for main steam valve control system model, progressively design virtual controlling, and introduce low-pass first order filter in every step, finally derive main steam valve of turbine generator dynamic surface control, overcome counter " differential blast " phenomenon that pushes away control, can guarantee half global stability of closed-loop control system, realized the fast and accurately tracking of turbodynamo merit angle to desired trajectory simultaneously.

2, technical scheme

Below in conjunction with the step in FB(flow block) 4, specifically introduce the technical scheme of this method for designing.

The infinitely great bus system schematic diagram of unit is as Fig. 1.

A kind of dynamic surface control method for opening of main throttle valve of steam turbine generator of the present invention, the method concrete steps are as follows:

The control system analysis of first step main steam valve of turbine generator and modeling

Closed-loop control system adopts degenerative control structure, and output quantity is turbodynamo merit angle.Designed closed-loop control system mainly comprises controller link and these two parts of system model, and its topology layout situation as shown in Figure 2.

Main steam valve control system model is described below:

$\left\{\begin{array}{c}\stackrel{\&CenterDot;}{\mathrm{\&delta;}}=\mathrm{\&omega;}-{\mathrm{\&omega;}}_0\\ \stackrel{\&CenterDot;}{\mathrm{\&omega;}}=-\frac{D}{H}(\mathrm{\&omega;}-{\mathrm{\&omega;}}_0)+\frac{{\mathrm{\&omega;}}_0}{H}(P_H+C_{\mathrm{ML}}{P}_{m0}-\frac{E_q^{\&prime;}{V}_s}{X_{\mathrm{d\&Sigma;}}^{\&prime;}}\sin \mathrm{\&delta;})\\ {\stackrel{\&CenterDot;}{P}}_H=-\frac{1}{T_{\mathrm{H\&Sigma;}}}(P_H-C_H{P}_{m0})+\frac{C_H}{T_{\mathrm{H\&Sigma;}}}u\end{array}\right.---\left(1\right)$

Wherein: δ represents turbodynamo merit angle;

δ ₀represent turbodynamo merit angle initial value;

ω represents generator amature speed;

ω ₀represent generator amature speed initial value;

P _hrepresent the mechanical output that high pressure cylinder produces;

P _mthe mechanical output that represents prime mover output;

P _m0the mechanical output initial value that represents prime mover output;

D represents ratio of damping;

H represents the moment of inertia of generator amature;

C _mLrepresent mesolow power partition coefficient;

C _hrepresent the non-distribution coefficient of high pressure cylinder power;

represent generator q axle transient potential;

V represents infinitely great bus voltage;

represent the equivalent electromotive force between generator and Infinite bus system;

T _{h ∑}represent high pressure cylinder porthole control system equivalent time constant;

U represents main steam valve of turbine generator control.

For the ease of design, define respectively three state variable x ₁, x ₂, x ₃as follows:

x ₁＝δ-δ ₀

x ₂＝ω-ω ₀

x ₃＝P _H-C _HP _m0

At this moment (1) just can be write as

$\left\{\begin{array}{c}{\stackrel{\&CenterDot;}{x}}_1=x_2\\ {\stackrel{\&CenterDot;}{x}}_2=k_1{x}_3+f_1(x_1,x_2)\\ {\stackrel{\&CenterDot;}{x}}_3=k_{2}u+f_2\left(x_3\right)\end{array}\right.---\left(2\right)$

Wherein:

$k_1=\frac{{\mathrm{\&omega;}}_0}{H},$

${\mathrm{<figure-callout\; id="2"\; label="k"\; filenames="HDA0000136315090000031.png,HDA0000136315090000032.png"\; state="\{\{state\}\}">k</figure-callout>}}_2=\frac{C_H}{T_{\mathrm{H\&Sigma;}}},$

$f_1(x_1,x_2)=-\frac{D}{H}{x}_2+\frac{{\mathrm{\&omega;}}_0}{H}{P}_{m0}(C_H+C_{\mathrm{ML}})-\frac{{\mathrm{\&omega;}}_0{E}_q^{\&prime;}{V}_s}{{\mathrm{HX}}_{\mathrm{d\&Sigma;}}^{\&prime;}}\sin (x_1+{\mathrm{\&delta;}}_0),$

$f_2\left(x_3\right)=-\frac{1}{T_{\mathrm{H\&Sigma;}}}{x}_3.$

The object of so processing is that system is turned to clear lower triangular form system, is convenient to control design.

The design of second step main steam valve of turbine generator dynamic surface control

As shown in Figure 3, design process is the process of progressively going forward one by one to main steam valve of turbine generator dynamic surface control inner structure, and one is divided into three small steps.

The first small step: suppose that desired trajectory is x _1d.Define first error surface S ₁for

S ₁＝x ₁-x _1d (3)

(3) differentiate is obtained

${\stackrel{\&CenterDot;}{S}}_1=x_2-{\stackrel{\&CenterDot;}{x}}_{1d}---\left(4\right)$

Design first virtual controlling amount for

${\stackrel{\&OverBar;}{x}}_2=-c_1{\mathrm{<figure-callout\; id="1"\; label="S"\; filenames="HDA0000136315090000021.png,HDA0000136315090000032.png"\; state="\{\{state\}\}">S</figure-callout>}}_1+{\stackrel{\&CenterDot;}{x}}_{1d}---\left(5\right)$

Wherein: c ₁represent to regulate parameter.

Will

be input to following low-pass first order filter

${\mathrm{\&tau;}}_2{\stackrel{\&CenterDot;}{x}}_{2d}+x_{2d}={\stackrel{\&OverBar;}{x}}_2---\left(6\right)$

Wherein: τ ₂represent time parameter;

X _2drepresent low-pass filter output.

The second small step: define second error surface S ₂for

S ₂＝x ₂-x _2d (7)

(7) differentiate is obtained

${\stackrel{\&CenterDot;}{S}}_2=k_1{x}_3+f_1(x_1,x_2)-{\stackrel{\&CenterDot;}{x}}_{2d}---\left(8\right)$

Design second virtual controlling amount

for

${\stackrel{\&OverBar;}{x}}_3=\frac{1}{k_1}[-f_1(x_1,x_2)+{\stackrel{\&CenterDot;}{x}}_{2d}{-c}_2{S}_2]---\left(9\right)$

Wherein: c ₂represent to regulate parameter.

can be obtained by (6)

${\stackrel{\&CenterDot;}{x}}_{2d}=\frac{{\stackrel{\&OverBar;}{x}}_2-x_{2d}}{{\mathrm{\&tau;}}_2}---\left(10\right)$

Will

be input to following low-pass first order filter

${\mathrm{\&tau;}}_3{\stackrel{\&CenterDot;}{x}}_{3d}+x_{3d}={\stackrel{\&OverBar;}{x}}_3---\left(11\right)$

Wherein: τ ₃represent time parameter;

X _3drepresent low-pass filter output.

The 3rd small step: define the 3rd error surface S ₃for

S ₃＝x ₃-x _3d (12)

(12) differentiate is obtained

${\stackrel{\&CenterDot;}{S}}_3=k_{2}u+f_2\left(x_3\right)-{\stackrel{\&CenterDot;}{x}}_{3d}---\left(13\right)$

Design main steam valve of turbine generator dynamic surface control u is

$u=\frac{1}{k_2}[-f_2\left(x_3\right)+{\stackrel{\&CenterDot;}{x}}_{3d}-c_3{S}_3]---\left(14\right)$

Wherein: c ₃represent to regulate parameter.

can be obtained by (11)

${\stackrel{\&CenterDot;}{x}}_{3d}=\frac{{\stackrel{\&OverBar;}{x}}_3-x_{3d}}{{\mathrm{\&tau;}}_3}---\left(15\right)$

So far, obtained main steam valve of turbine generator dynamic surface control.

The 3rd step tracking performance check regulates with parameter

Whether this step meets design requirement checking system tracking performance, and suitably regulates control parameter, as shown in Figure 4.By means of conventional numerical evaluation and Control System Imitation instrument Matlab 7.0, carry out.

Parameter c ₁, c ₂, c ₃, τ ₂, τ ₃for regulating parameter.If tracking error is excessive, do not meet design requirement, can increase c ₁, c ₂, c ₃value or reduce τ ₂, τ ₃value.On the one hand, increase c ₁, c ₂, c ₃be equivalent to increase control intensity; On the other hand, reduce τ ₂, τ ₃be equivalent to improve the response speed of system.Therefore these two kinds of ways all contribute to improve system keeps track performance.

The 4th step design finishes

Whole design process emphasis has been considered the demand for control of three aspects, is respectively the simplicity of design, the stability of closed-loop system, the quick accuracy of tracking.Around these three aspects, first in the above-mentioned first step, determined the concrete formation of closed-loop control system; In second step, emphasis has provided main steam valve of turbine generator dynamic surface control method for designing, mainly comprises three little steps; In the 3rd step article in order to improve the parameter adjusting method of tracking performance; After above steps, design finishes.

3, advantage and effect

The present invention is directed to the infinitely great bus system of unit, provide a kind of dynamic surface control method for opening of main throttle valve of steam turbine generator, for controlling turbodynamo merit angle.Concrete advantage comprises two aspects: one, to compare with the disposal route of current existence, and this method is very easy in CONTROLLER DESIGN process, there will not be counter " differential blast " phenomenon that pushes away control; Its two, by adjusted design parameter, can be simply, desired trajectory is followed the tracks of at control system merit angle quickly and accurately neatly.

(4) accompanying drawing explanation

Fig. 1: the infinitely great bus system schematic diagram of unit of the present invention

Fig. 2: closed-loop control system structure of the present invention and assembly annexation schematic diagram

Fig. 3: control system inner structure schematic diagram of the present invention

Fig. 4: main steam valve dynamic surface control design cycle schematic diagram of the present invention

Fig. 5 .1: c in embodiment of the present invention () ₁=1, c ₂=20, c ₃=10, τ ₂=0.1, τ ₃the tracking effect figure of=0.1 o'clock

Fig. 5 .2: c in embodiment of the present invention () ₁=1, c ₂=20, c ₃=10, τ ₂=0.1, τ ₃the tracking error figure of=0.1 o'clock

Fig. 6 .1: c in embodiment of the present invention () ₁=2, c ₂=30, c ₃=15, τ ₂=0.01, τ ₃the tracking effect figure of=0.01 o'clock

Fig. 6 .2: c in embodiment of the present invention () ₁=2, c ₂=30, c ₃=15, τ ₂=0.01, τ ₃the tracking error figure of=0.01 o'clock

Label in figure, symbol and lines etc. are described as follows:

Horizontal ordinate in Fig. 5 .1-5.2, Fig. 6 .1-6.2 represents simulation time, and unit is second; In Fig. 5 .1, Fig. 6 .1, ordinate represents turbodynamo merit angle tracking effect, unit degree of being; In Fig. 5 .2, Fig. 6 .2, ordinate represents turbodynamo merit angle tracking error, unit degree of being; Dotted line in Fig. 5 .1, Fig. 6 .1 represents desired trajectory signal wire, and solid line represents actual turbodynamo merit angle signal line.

(5) embodiment

Design object of the present invention comprises two aspects: one, realize the simplification that main steam valve of turbine generator is controlled design; Its two, realize the quick accurate tracking desired trajectory in turbodynamo merit angle of closed-loop system, specific targets are: turbodynamo merit angle tracking error in 1 second is less than 0.5 degree angle.Fig. 1 is the infinitely great bus system schematic diagram of unit of the present invention.

In concrete enforcement, the emulation of dynamic surface control method for opening of main throttle valve and closed-loop control system and check all realize by means of the Simulink tool box in Matlab7.0.Here by introducing one, there is certain representational embodiment, further illustrate relevant design in technical solution of the present invention and the control method of design parameter.

Embodiment (one) is by increasing c ₁, c ₂, c ₃value and reduce τ ₂, τ ₃value to realize accuracy and the rapidity of the angle tracking of turbodynamo merit.

Embodiment (one)

The first step: main steam valve of turbine generator control system analysis and modeling

Closed-loop control system adopts degenerative control structure, output quantity turbodynamo merit angle.Designed closed-loop control system is mainly controller link and these two parts of system model, and its topology layout situation as shown in Figure 2.

Main steam valve control system model $\left\{\begin{array}{c}\stackrel{\&CenterDot;}{\mathrm{\&delta;}}=\mathrm{\&omega;}-{\mathrm{\&omega;}}_0\\ \stackrel{\&CenterDot;}{\mathrm{\&omega;}}=-\frac{D}{H}(\mathrm{\&omega;}-{\mathrm{\&omega;}}_0)+\frac{{\mathrm{\&omega;}}_0}{H}(P_H+C_{\mathrm{ML}}{P}_{m0}-\frac{E_q^{\&prime;}{V}_s}{X_{\mathrm{d\&Sigma;}}^{\&prime;}}\sin \mathrm{\&delta;})\\ {\stackrel{\&CenterDot;}{P}}_H=-\frac{1}{T_{\mathrm{H\&Sigma;}}}(P_H-C_H{P}_{m0})+\frac{C_H}{T_{\mathrm{H\&Sigma;}}}u\end{array}\right.---\left(1\right)$

In, according to the real system empirical data of certain power plant, parameter is chosen as follows:

δ ₀＝60，ω ₀＝218，P _m0＝0.8，D＝5，

H＝8，C _ML＝0.7，C _H＝0.3，

V _s＝1，

T _H∑＝0.4，

State variable initial value is set to x ₁=0, x ₂=0, x ₃=0.

Second step: main steam valve of turbine generator dynamic surface control design

As shown in Figure 2, adopt the unit negative feedback control structure of output quantity (angle signal).Main steam valve dynamic surface control device inner structure as shown in Figure 3.Utilize .m Programming with Pascal Language under Matlab 7.0 environment to realize the 26S Proteasome Structure and Function of main steam valve dynamic surface control device.The input signal that is controller is error signal (deducting output signal by reference signal tries to achieve), with this, builds first virtual controlling amount, is entered into first low-pass first order filter and is exported; By first low-pass first order filter output, build second virtual controlling amount, be entered into second low-pass first order filter and exported; By second low-pass first order filter output design main steam valve dynamic surface control device.

The first small step: set desired trajectory x _1d=60+sint, with the state x of feedback acquisition ₁subtract each other and obtain S ₁=x ₁-x _1d, to x _1ddifferentiate obtains

parameter c ₁value is 1, calculates will

be input to timeconstantτ ₂value is 0.1 low-pass first order filter

in obtain exporting x _2d.

The second small step: according to the x of low-pass first order filter output _2dand formula obtain

by x _2dthe state x obtaining with feedback ₂subtract each other and obtain S ₂=x ₂-x _2d.Parameter c ₂value is 20, according to

calculate

will

be input to timeconstantτ ₃value is 0.1 low-pass first order filter

obtain exporting x _3d.

The 3rd small step: according to low-pass first order filter output x _3dand formula

obtain

by x _3dthe state x obtaining with feedback ₃subtract each other and obtain S ₃=x ₃-x _3d.Parameter c ₃value is 10, calculates main steam valve of turbine generator dynamic surface control

under Matlab 7.0 environment, real system is carried out to emulation, simulation result is shown in shown in Fig. 5 .1-5.2.

The 3rd step: tracking performance check regulates with parameter

Whether this step meets design requirement checking system tracking performance, as shown in Figure 4.By means of conventional numerical evaluation and Control System Imitation instrument Matlab 7.0, carry out.

Parameter c ₁, c ₂, c ₃, τ ₂, τ ₃for regulating parameter.If tracking error is excessive, do not meet design requirement, can increase c ₁, c ₂, c ₃value and reduce τ ₂, τ ₃value.By c ₁, c ₂, c ₃increase to respectively 2,30,15, by τ ₂, τ ₃be reduced to 0.01,0.01, the simulation result after parameter regulates is shown in shown in Fig. 6 .1-6.2.After parameter regulates, accuracy and the rapidity of tracking performance greatly improve, and therefore this adjusting parameter way contributes to improve system keeps track performance.

The 4th step: design finishes

Whole design process emphasis has been considered the demand for control of three aspects, the simplicity designing respectively, the stability of closed-loop system, the quick accuracy of tracking.Around these three aspects, first in the above-mentioned first step, determined the concrete formation of closed-loop control system; In second step, emphasis has provided main steam valve of turbine generator dynamic surface control method for designing, mainly comprises three little steps; In the 3rd step article in order to improve the parameter adjusting method of tracking performance; After above steps, design finishes.

Claims (1)

1. a dynamic surface control method for opening of main throttle valve of steam turbine generator, is characterized in that: the method concrete steps are as follows:

Step 1: main steam valve of turbine generator control system analysis and modeling

Closed-loop control system adopts degenerative control structure, and output quantity is turbodynamo merit angle; Designed closed-loop control system comprises controller link and these two parts of system model;

Main steam valve control system model is described below:

$\left\{\begin{array}{c}\stackrel{\&CenterDot;}{\mathrm{\&delta;}}=\mathrm{\&omega;}-{\mathrm{\&omega;}}_0\\ \stackrel{\&CenterDot;}{\mathrm{\&omega;}}=-\frac{D}{H}(\mathrm{\&omega;}-{\mathrm{\&omega;}}_0)+\frac{{\mathrm{\&omega;}}_0}{H}(P_H+C_{\mathrm{ML}}{P}_{m0}-\frac{E_q^{\&prime;}{V}_s}{X_{\mathrm{d\&Sigma;}}^{\&prime;}}\sin \mathrm{\&delta;})\\ {\stackrel{\&CenterDot;}{P}}_H=\frac{1}{T_{\mathrm{H\&Sigma;}}}(P_H-C_H{P}_{m0})+\frac{C_H}{T_{\mathrm{H\&Sigma;}}}u\end{array}\right.---\left(1\right)$

Wherein: δ represents turbodynamo merit angle;

δ ₀represent turbodynamo merit angle initial value;

ω represents generator amature speed;

ω ₀represent generator amature speed initial value;

P _hrepresent the mechanical output that high pressure cylinder produces;

P _mthe mechanical output that represents prime mover output;

P _m0the mechanical output initial value that represents prime mover output;

D represents ratio of damping;

H represents the moment of inertia of generator amature;

C _mLrepresent mesolow power partition coefficient;

C _hrepresent the non-distribution coefficient of high pressure cylinder power;

E' _qrepresent generator q axle transient potential;

V _srepresent infinitely great bus voltage;

X' _{d Σ}represent the equivalent electromotive force between generator and Infinite bus system;

T _{h Σ}represent high pressure cylinder porthole control system equivalent time constant;

U represents main steam valve of turbine generator control;

For the ease of design, define respectively three state variable x ₁, x ₂, x ₃as follows:

x ₁=δ-δ ₀

x ₂=ω-ω ₀

x ₃=P _H-C _HP _m0

At this moment (1) just can be write as

$\left\{\begin{array}{c}{\stackrel{\&CenterDot;}{x}}_1=x_2\\ {\stackrel{\&CenterDot;}{x}}_2=k_1{x}_3+f_1(x_1,x_2)\\ {\stackrel{\&CenterDot;}{x}}_3=k_{2}u+f_2\left(x_3\right)\end{array}\right.---\left(2\right)$

Wherein:

$k_1=\frac{{\mathrm{\&omega;}}_0}{H},$

$k_2=\frac{C_H}{T_{\mathrm{H\&Sigma;}}},$

$f_1(x_1,x_2)=-\frac{D}{H}{x}_2+\frac{{\mathrm{\&omega;}}_0}{H}{P}_{m0}(C_H+C_{\mathrm{ML}})-\frac{{\mathrm{\&omega;}}_0{E}_q^{\&prime;}{V}_s}{{\mathrm{HX}}_{\mathrm{d\&Sigma;}}^{\&prime;}}\sin (x_1+{\mathrm{\&delta;}}_0),$

$f_2\left(x_3\right)=-\frac{1}{T_{\mathrm{H\&Sigma;}}}{x}_3;$

The object of so processing is that system is turned to clear lower triangular form system, is convenient to control design;

Step 2: main steam valve of turbine generator dynamic surface control design

The design of main steam valve of turbine generator dynamic surface control is the process of progressively going forward one by one, and one is divided into three small steps:

The first small step: suppose that desired trajectory is x _1d, define first error surface S ₁for

S ₁=x ₁-x _1d （3）

(3) differentiate is obtained

${\stackrel{\&CenterDot;}{S}}_1=x_2-{\stackrel{\&CenterDot;}{x}}_{1d}---\left(4\right)$

Design first virtual controlling amount

for

${\stackrel{\&OverBar;}{x}}_2={-c}_1{S}_1+{\stackrel{\&CenterDot;}{x}}_{1d}---\left(5\right)$

Wherein: c ₁represent to regulate parameter;

Will

be input to following low-pass first order filter

${\mathrm{\&tau;}}_2{\stackrel{\&CenterDot;}{x}}_{2d}+x_{2d}={\stackrel{\&OverBar;}{x}}_2---\left(6\right)$

Wherein: τ ₂represent time parameter;

X _2drepresent low-pass filter output;

The second small step: define second error surface S ₂for

S ₂=x ₂-x _2d （7）

(7) differentiate is obtained

${\stackrel{\&CenterDot;}{S}}_2=k_1{x}_3+f_1(x_1,x_2)-{\stackrel{\&CenterDot;}{x}}_{2d}---\left(8\right)$

Design second virtual controlling amount

for

${\stackrel{\&OverBar;}{x}}_3=\frac{1}{k_1}\&lsqb;-f_1(x_1,x_2)+{\stackrel{\&CenterDot;}{x}}_{2d}-c_2{S}_2\&rsqb;---\left(9\right)$

Wherein: c ₂represent to regulate parameter;

can be obtained by (6)

${\stackrel{\&CenterDot;}{x}}_{2d}=\frac{{\stackrel{\&OverBar;}{x}}_2-x_{2d}}{{\mathrm{\&tau;}}_2}---\left(10\right)$

Will be input to following low-pass first order filter

${\mathrm{\&tau;}}_3{\stackrel{\&CenterDot;}{x}}_{3d}+x_{3d}={\stackrel{\&OverBar;}{x}}_3---\left(11\right)$

Wherein: τ ₃represent time parameter;

X _3drepresent low-pass filter output;

The 3rd small step: define the 3rd error surface S ₃for

S ₃=x ₃-x _3d （12）

(12) differentiate is obtained

${\stackrel{\&CenterDot;}{S}}_3=k_{2}u+f_2\left(x_3\right)-{\stackrel{\&CenterDot;}{x}}_{3d}---\left(13\right)$

Design main steam valve of turbine generator dynamic surface control u is

$u=\frac{1}{k_2}\&lsqb;-f_2\left(x_3\right)+{\stackrel{\&CenterDot;}{x}}_{3d}-c_3{S}_3\&rsqb;---\left(14\right)$

Wherein: c ₃represent to regulate parameter;

can be obtained by (11)

${\stackrel{\&CenterDot;}{x}}_{3d}=\frac{{\stackrel{\&OverBar;}{x}}_3-x_{3d}}{{\mathrm{\&tau;}}_3}---\left(15\right)$

So far, obtained main steam valve of turbine generator dynamic surface control;

Step 3: tracking performance check regulates with parameter

Whether this step meets design requirement checking system tracking performance, and suitably regulates and control parameter, by means of conventional numerical evaluation and Control System Imitation instrument Matlab7.0, carries out;

Parameter c ₁, c ₂, c ₃, τ ₂, τ ₃for regulating parameter, if tracking error is excessive, do not meet design requirement, increase c ₁, c ₂, c ₃value or reduce τ ₂, τ ₃value; On the one hand, increase c ₁, c ₂, c ₃be equivalent to increase control intensity; On the other hand, reduce τ ₂, τ ₃be equivalent to improve the response speed of system; Therefore these two kinds of ways all contribute to improve system keeps track performance;

Step 4: design finishes

Whole design process has been considered the demand for control of three aspects, is respectively the simplicity of design, the stability of closed-loop system, the quick accuracy of tracking; Around these three aspects, first in above-mentioned steps one, determined the concrete formation of closed-loop control system; In step 2, provide main steam valve of turbine generator dynamic surface control method for designing, comprised three little steps; In step 3, provided in order to improve the parameter adjusting method of tracking performance; After above steps, design finishes.

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