CN105006830A - Method for establishing sliding-mode static Var compensator of isolated wind-diesel hybrid power system - Google Patents

Abstract

The invention relates to a method for establishing a sliding-mode static Var compensator of an isolated wind-diesel hybrid power system, which comprises the steps of (1) establishing a closed-loop state equation for a traditional SVC mathematical model; (2) establishing a sliding-mode switching surface s=Cx, wherein C represents a constant matrix; (3) presetting a stability criterion condition by utilizing the sliding-mode switching surface s established in the step (2), and designing a sliding-mode controller u=(CB)-1[-CAx-CPw-epsilon sgn(s)-ks]; (4) assigning H=-(CB)-1(CA+kC), n=-(CB)-1CP, m=-(CB)-1 epsilon, simplifying the sliding-mode controller to be u=Hx+nw+msgn(s), adopting the sliding-mode controller u to be a complementary controller of an SVC control system, and controlling the sliding-mode reactive power compensation on the power system. Compared with the prior art, the method is good in invariance and robustness for external disturbance, model uncertainty and unmodeled dynamics that meet matched conditions. Therefore, the power-angle and voltage stability problem of a new energy power system is effectively solved. Meanwhile, the transient stability is improved.

Description

The sliding formwork Static Var Compensator method for building up of isolated wind bavin hybrid power system

Technical field

The present invention relates to New-energy power system Static Var Compensator design field, especially relate to a kind of sliding formwork Static Var Compensator method for building up of isolated wind bavin hybrid power system.

Background technology

Along with the deterioration of environment and the shortage of fossil energy, energy-saving and emission-reduction, accelerate development the grand strategy that continuable clean energy resource becomes global evolution.Along with the maturation of wind generating technology, the developing rapidly of wind-powered electricity generation becomes in world wide and has scale and the best generation of electricity by new energy mode of commercial development prospect.The stand alone generating system of its apoplexy bavin complementation can solve the powerup issue in island and outlying village, wind power system wind-force sufficient and meet load request be less than the output of wind generator system time, powered separately by wind generator system, start diesel engine supplementary power when load request cannot be met.In addition due to randomness, the intermittence of wind, can affect to system voltage stabilizes, system voltage even can be caused to collapse, and therefore in wind energy turbine set, reactive power compensation problem develops along with wind-powered electricity generation the focus becoming research with the continuous expansion of installed capacity of wind-driven power gradually rapidly.And Static Var Compensator (SVC) can inject perception or capacitive reactive power to electrical network dynamically, suppress voltage disturbance fast, very be applicable to the reactive power compensation of wind energy turbine set, so the transient stability that the control strategy improving SVC improves electric power system has further become an important subject in current electric power system.

In recent years, Chinese scholars proposes different SVC control strategies, as PI, self adaptation, fuzzy, sliding formwork, genetic algorithm, neural net etc., improves the transient stability of electric power system and dynamic quality further and achieves relevant achievement in research.Document " Tuning of SVC proportional-integral damping controllerto enhance power systems dynamic stability, ELLITHY K, SAID S, North AmericanPower Symposium " the PI damping controller of the Static Var Compensator of the system dynamic stability that can increase electric power is devised for one machine infinity bus system, Method of Pole Placement is utilized to determine the yield value of PI controller, but its deficiency is applied in this complicated nonlinear system of SVC by traditional PI controller, rapidity and stability cannot be met simultaneously, the accurate control of the output impedance to SVC cannot be met.Document " the new adaptive internal model control of one of static var compensator robust control; Fu Jun; Zhao Jun etc.; Proceedings of the CSEE; 2006 " is for containing the one machine infinity bus system of unknown parameter with SVC, control and a kind of NEW ADAPTIVE backstepping method design SVC additional controller in conjunction with PI, although this method improves the stability of system, corresponding research is not provided for the system of actual complex and grid-connected power generation system.Document " Fuzzy Variable-Structure Control of SVC is on the impact of stability of power system; Liu Ruiye; Liu Baozhu; relay; 2001 ", for the one machine infinity bus system installing SVC on power transmission line, adopts fuzzy variable structure to control SVC, and then improves the damping characteristic of system, suppress the voltage fluctuation in transient response but need, the control effects of SVC when will realize in conjunction with automatic voltage regulator and not consider multiple feed.Document " research of SVC and generator additional excitation fuzzy variable structure Comprehensive Control; Liu Ruiye; Liu Baozhu; relay; 2002 " is then for the interconnected electric power system of multimachine, SVC wherein and generator are carried out to the design of additional excitation Fuzzy Variable-Structure Control device, though this method can improve angle stability and the Enhancement of Transient Voltage Stability of electric power system, but shortcoming is that SVC is reduced to first order inertial loop, have ignored the control effects of the not real reflection SVC such as the amplitude limit link of the angle of flow and the delay link of Trigger Angle.Document " based on the design and implimentation of the SVC voltage controller of fuzzy-PI; Dai Yuanhai; Peng Jianchun etc.; observation and control technology; 2009 " proposes for the unit electric power system of open loop the design carrying out SVC controller with fuzzy-PI, and the document adopts DSP to be the design of main control chip to SVC software and hardware, but from its simulation waveform, before and after improving, waveform does not significantly change, and its control effects is not obvious.Document " the intelligent adaptive PID controller design of static var compensator; Peng Jianchun; Huang Chun etc.; Hunan University's journal; 1990 " proposes self adaptation Backstepping for the one machine infinity bus system containing SVC, complete remain system nonlinear characteristic and improve the response speed of system, breach classical certainty, equivalence principle, but the adaptive control incipient stage differs, guarantee is surely stable, realize accurate tracking input and need certain hour, nonlinear organization change system cannot be processed, do not possess the feasibility of engineer applied.Document " the SVC adaptive fuzzy controller research of damping interconnection low-frequency oscillation; Yang Xiaodong, room is medium greatly, Proceedings of the CSEE; 2003 " proposes genetic algorithm and makes up its shortcoming in conjunction with TABU search, and then proposes the coordinated measure of PSS and SVC based on combination algorithm.Fuzzy theory, Cooperative Evolutionary Algorithm and immune algorithm combine and solve the Harmonic Control of SVC device by document " based on multiple FACTS element cooperation control of fuzzy hybrid evolution algorithm; Liu Qing; Li Liying etc.; Electric Power Automation Equipment; 2010 ", keep good damped oscillation characteristic between multiple controller.Document " based on the SVC voltage stability control Ma Zhaoxing of neural net, Wan Qiulan etc., protecting electrical power system and control, 2011 " proposes new neural network PID control structure, maintains system voltage stabilizes.The advantage of these Based Intelligent Control is in conjunction with artificial intelligence theory, there is self-learning capability, be applicable to non-linear, the uncertain problem of process, improve adaptive ability and the robustness of SVC, but intellectual technology itself still has a large amount of underlying issue to need to solve at present, is still in conceptual phase.

Sliding formwork control realization is simple, and it has consistency to the external interference of Satisfying Matching Conditions, the uncertainty of model and Unmarried pregnancy, therefore can with the angle stability solved in electric power system and Voltage-stabilizing Problems.Document " Nonlinear Grey Sliding Mode of Static Var Compensator controls research; Du Jiwei; Wang Ben etc.; electrical applications; 2007 " is for one machine infinity bus system, propose " shake " that Nonlinear Grey Sliding Mode control SVC effectively weakens System with Sliding Mode Controller existence, to improve the transient stability of system; Document " design of the Fuzzy Sliding Model Controller of SVC, Wang Yong, Xiao Renshan, Guangxi electric power, 2003 " adopts fuzzy sliding mode control SVC to improve the angle stability of system.Although these methods improve the angle stability of system, also weaken the chattering phenomenon of general variable structure control system, their research object is all one machine infinity bus system, all do not consider yet generation of electricity by new energy as after wind power integration on the impact of system voltage.Document " is considered the Static Var Compensator adaptive sliding mode controller design of model uncertainty and time delay; Wang Xi; Wang Yuhong; Acta Physica Sinica; 2014 " for the model uncertainty of SVC and delay problem and is proposed adaptive sliding-mode observer method to improve the transient stability of system, but its problem is for traditional electric power system equally, and does not study the situation of grid-connected power generation system.

Summary of the invention

Object of the present invention be exactly provide to overcome defect that above-mentioned prior art exists a kind of for wind bavin hybrid power system, the sliding formwork Static Var Compensator method for building up external interference such as SVC equivalent time constant is uncertain to the isolated wind bavin hybrid power system of robustness.

Object of the present invention can be achieved through the following technical solutions:

A sliding formwork Static Var Compensator method for building up for isolated wind bavin hybrid power system, is characterized in that, comprise the following steps:

(1) the closed loop states equation of traditional SVC Mathematical Modeling is set up:

$\left\{\begin{array}{c}\stackrel{\·}{x}=Ax+Bu+Pw\\ y=C_{0}x\end{array}\right.$

Wherein, x=[Δ B _sVCb' _sVCΔ α] ^t, u is control variables, sytem matrix $A=\left[\begin{array}{ccc}-\frac{1}{T_{\mathrm{\α}}}& 0& \frac{K_{\mathrm{\α}}}{T_{\mathrm{\α}}}\\ \frac{1}{T_d}& -\frac{1}{T_d}& 0\\ 0& 0& -\frac{1}{T_R}\end{array}\right],$ Input matrix $B=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Perturbation matrix $P=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Output matrix C ₀=[0 1 0], w=Δ V _ref-Δ V, Δ V _reffor the reference value of voltage deviation amount, Δ V is the actual value of voltage deviation, K _rfor the gain of Reactive-power control device, T _rfor the time constant of adjuster, K _αfor IGBT group gain, T _αfor IGBT group time of delay, T _dfor the average dead time time of zero crossing place SVC in three-phase system, B' _sVCfor the idle susceptance of SVC, Δ B _sVCfor the variable quantity of idle susceptance, Δ α is the variable quantity at IGBT group angle;

(2) according to the state equation design sliding formwork diverter surface s=Cx that step (1) is set up, wherein C is constant matrices;

(3) the sliding formwork diverter surface s that step (2) is set up is utilized, the stability criteria condition of given electric power system, design sliding mode controller u=(CB) ^-1[-CAx-CPw-ε sgn (s)-ks], wherein, constant ε, k are velocity of approach, ε > 0, k > 0;

(4) sliding mode controller u is added in SVC control system as additional controller, sliding formwork the control of reactive power compensating is carried out to electric power system.

In described step (1), (A, B) is completely controlled.

Described step (2) comprises the following steps:

(2-1) A, B piecemeal is obtained $A=\left[\begin{array}{cc}{A}_{11}& A_{12}\\ A_{21}& A_{22}\end{array}\right],B=\left[\begin{array}{c}{B}_1\\ B_2\end{array}\right],$ Wherein $A_{11}=\left[\begin{array}{cc}-\frac{1}{T_{\mathrm{\α}}}& 0\\ \frac{1}{T_d}& -\frac{1}{T_d}\end{array}\right],A_{12}=\left[\begin{array}{c}\frac{K_{\mathrm{\α}}}{T_{\mathrm{\α}}}\\ 0\end{array}\right],$ A ₂₁＝[0 0]， $A_{22}=\[-\frac{1}{T_R}\],B_1=\left[\begin{array}{c}0\\ 0\end{array}\right],B_2=\[-\frac{K_R}{T_R}\];$

(2-2) A is calculated ₁₁limit p ₁=[λ ₁, λ ₂];

(2-3) computing mode feedback matrix K=place (A ₁₁, A ₁₂, p ₁), wherein, place is robust features structure POLE PLACEMENT USING function;

(2-4) C=[K, I is got _l], set up sliding formwork diverter surface s=Cx, wherein, I _lfor unit battle array.

In described step (4), be u=Hx+nw+msgn (s) by the sliding mode controller abbreviation of design, wherein H=-(CB) ^-1(CA+kC), n=-(CB) ^-1cP, m=-(CB) ^-1ε, sgn () are sign function, $\mathrm{sgn}\left(s\right)=\left\{\begin{array}{cc}1,& s\&GreaterEqual;0\\ 0,& s<0\end{array}\right..$

In described step (3), the given stability criteria condition of electric power system is: if condition | w|<a sets up, and wherein a has got dividing value, then exist make for all t and x ∈ B ^c(η), electric power system keeps stable on sliding formwork diverter surface s (t)=0, wherein B ^c(η) be take x=0 as the centre of sphere, the benefit of the η closed sphere B (η) that is radius, q is positive definite matrix, λ _min(Q) be the characteristic value of matrix Q.

In described step (4), get 0 < ε < 1, k >=10.

Compared with prior art, the present invention has the following advantages:

(1) sliding mode control theory is adopted for the Static Var Compensator SVC in wind bavin hybrid power system, sliding formwork controls to have consistency to the external interference of Satisfying Matching Conditions, the uncertainty of model and Unmarried pregnancy, effectively solves the angle stability in New-energy power system and Voltage-stabilizing Problems.

(2) SVC adds sliding mode controller and has robustness for external interference such as its equivalent time constant are uncertain, improves the transient stability of New-energy power system.

(3) after adding step disturbance to the blower fan input power link of system, designed SVC sliding mode controller can provide reactive power compensation to system more quickly, effectively to suppress voltage disturbance, thus improves the transient stability of New-energy power system.

(4), after adding dissimilar load or burden without work disturbance to system, designed SVC sliding mode controller more effectively can provide required idle to system, and then strengthens the transient stability of system.

(5) control method of the present invention realizes simple, and feasibility is high.

Accompanying drawing explanation

Fig. 1 is the schematic diagram of the wind-Chai hybrid power system containing SVC;

Fig. 2 is the Mathematical Modeling of SVC;

Fig. 3 is the transfer function block diagram of the wind-Chai hybrid power system containing SVC;

Fig. 4 is the Mathematical Modeling of SVC sliding mode controller of the present invention;

Fig. 5 is the wind-Chai hybrid power system transfer function block diagram of the present invention with sliding formwork SVC controller;

Fig. 6 (a)-Fig. 6 (d) be respectively wind bavin hybrid power system 1% step signal and 1% random disturbance signal acting in conjunction under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity;

Fig. 7 (a)-Fig. 7 (d) be respectively wind bavin hybrid power system I 1% blower fan power output step disturbance signal and 1% the acting in conjunction of step load disturbing signal under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity;

Fig. 8 (a)-Fig. 8 (d) be respectively wind bavin hybrid power system I 1% blower fan power output step disturbance signal and 1% the acting in conjunction of random load disturbing signal under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity;

Fig. 9 (a)-Fig. 9 (d) be respectively wind bavin hybrid power system II 1% blower fan power output step disturbance signal and 1% the acting in conjunction of step load disturbing signal under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity;

Figure 10 (a)-Figure 10 (d) be respectively wind bavin hybrid power system II 1% blower fan power output step disturbance signal and 1% the acting in conjunction of random load disturbing signal under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity;

Figure 11 (a)-Figure 11 (d) be respectively wind bavin hybrid power system III 1% blower fan power output step disturbance signal and 1% the acting in conjunction of step load disturbing signal under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity;

Figure 12 (a)-Figure 12 (d) be respectively wind bavin hybrid power system III 1% blower fan power output step disturbance signal and 1% the acting in conjunction of random load disturbing signal under, the transient response of the variable quantity of the reactive power that system port reactive voltage variable quantity, SVC send, diesel generation machine equipment reactive power and induction generator reactive power variable quantity.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.The present embodiment is implemented premised on technical solution of the present invention, give detailed execution mode and concrete operating process, but protection scope of the present invention is not limited to following embodiment.

(1) traditional SVC model is considered

Fig. 1 is the structural representation of traditional SVC wind-Chai hybrid power system, and Fig. 2 is the Mathematical Modeling of traditional SVC, and Fig. 3 is the transfer function schematic diagram of traditional SVC wind-Chai hybrid power system.

For traditional SVC Mathematical Modeling as shown in Figure 2, its state space equation is:

$\left\{\begin{array}{c}\stackrel{\&CenterDot;}{x}=Ax+Bu+Pw\\ y=C_{0}x\end{array}\right.$

Wherein, u is control variables, w=Δ V _ref-Δ V, sytem matrix $A=\left[\begin{array}{ccc}-\frac{1}{T_{\mathrm{\&alpha;}}}& 0& \frac{K_{\mathrm{\&alpha;}}}{T_{\mathrm{\&alpha;}}}\\ \frac{1}{T_d}& -\frac{1}{T_d}& 0\\ 0& 0& -\frac{1}{T_R}\end{array}\right],$ X=[Δ B _sVCb' _sVCΔ α] ^t, input matrix $B=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Δ V is the actual value of voltage deviation, perturbation matrix $P=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Δ V _reffor the reference value of voltage deviation, output matrix C ₀=[0 1 0], K _rfor the gain of Reactive-power control device, T _rfor the time constant of adjuster, K _αfor IGBT group gain, T _αfor IGBT group time of delay, T _dfor the average dead time time of zero crossing place SVC in three-phase system, B' _sVCfor the idle susceptance of SVC, Δ B _sVCfor the variable quantity of idle susceptance, Δ α is the variable quantity at IGBT group angle, and in figure, α ° is thyristor nominal Trigger Angle.(2) design principle controlling sliding formwork Static Var Compensator in the automatic idle control of isolated wind bavin hybrid power system of Static Var Compensator based on sliding formwork of the present invention

Fig. 4 is the Mathematical Modeling of SVC sliding mode controller of the present invention; Fig. 5 is the wind-Chai hybrid power system transfer function schematic diagram of the present invention with sliding formwork SVC controller.Before CONTROLLER DESIGN parameter, first provide a hypothesis,

Suppose 1: matrix is completely controlled to (A, B).

Consider the state space equation of following SVC

$\stackrel{\&CenterDot;}{x}=Ax+Bu+Pw$

Design sliding-mode surface meets equation s=Cx.

Namely object of the present invention is design sliding formwork SVC controller:

u＝(CB) ^-1[-CAx-CPw-εsgn(s)-ks]

Calm and isolate wind bavin hybrid power system.The stability of sliding mode and the design of controller can be realized by following theorem 1 and theorem 2.

Theorem 1: if condition | w|<a, a > 0, a sets up for there being dividing value, then exist make for all t and x ∈ B ^c(η), wind bavin hybrid power system keeps stable on sliding-mode surface s (t)=0.

Prove: order

$\tilde{A}=A-B{\left(CB\right)}^{-1}CA,\tilde{F}=P-B{\left(CB\right)}^{-1}CP,$

Then the state space equation of SVC can be expressed as

$\stackrel{\&CenterDot;}{x}=\tilde{A}x+\tilde{F}w$

Structure liapunov function

$V\left(x\right)=x^T\left(t\right)\tilde{P}x\left(t\right)$

To V (x) differentiate and by equation substitute into

Wherein it is Lyapunov Equation solution.

For given positive definite symmetric matrices Q, prove that equation can be summarized as

$\stackrel{\&CenterDot;}{V}\left(x\right)\&le;-{\mathrm{\&lambda;}}_{min}\left(Q\right)\left|\right|x\left(t\right)|{|}^2+2a|\left|\tilde{F}\right|\left|\right|\left|\tilde{P}\right|\left|\right|\left|x\left(t\right)\right||$

Because λ _min(Q) > 0, so for all t, as x ∈ B ^c(η), time, system is stable.Wherein B ^c(η) being take x=0 as the centre of sphere, and η is the closed sphere B of radius ^c(η) benefit.Therefore

$\stackrel{\&CenterDot;}{V}\left(x\right)<0$

Namely system is stable.

Theorem 2: if variable-structure controller meets following equation

u＝(CB) ^-1[-CAx-CPw-εsgn(s)-ks]

Then system meets reaching condition.

Prove: by formula s=Cx and then have

$s\stackrel{\&CenterDot;}{s}=-\mathrm{\&epsiv;}\mathrm{sgn}\left(s\right)-ks=-\mathrm{\&epsiv;}\left|s\right|-{\mathrm{ks}}^2<0$

Wherein, ε > 0, k > 0, namely system meets reaching condition.

So controller makes the movement locus of system remain near sliding mode.

(3) method for designing controlling sliding formwork Static Var Compensator in the automatic idle control of isolated wind bavin hybrid power system of Static Var Compensator based on sliding formwork of the present invention

The sliding formwork that the present invention proposes controls the method for designing of Static Var Compensator, after the Mathematical Modeling establishing traditional SVC, carries out according to the following step:

1) the closed loop states equation expression formula of traditional SVC Mathematical Modeling is set up y=C ₀x, wherein u is control variables, w=Δ V _ref-Δ V, sytem matrix $A=\left[\begin{array}{ccc}-\frac{1}{T_{\mathrm{\&alpha;}}}& 0& \frac{K_{\mathrm{\&alpha;}}}{T_{\mathrm{\&alpha;}}}\\ \frac{1}{T_d}& -\frac{1}{T_d}& 0\\ 0& 0& -\frac{1}{T_R}\end{array}\right],$ Input matrix $B=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Perturbation matrix $P=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Output matrix C ₀=[0 1 0], Δ V _reffor the reference value of voltage deviation amount.

2) design sliding formwork diverter surface s=Cx, wherein C is the constant matrices with suitable dimension.A, B are carried out piecemeal obtain $A=\left[\begin{array}{cc}{A}_{11}& A_{12}\\ A_{21}& A_{22}\end{array}\right],B=\left[\begin{array}{c}{B}_1\\ B_2\end{array}\right].$ Wherein, $A_{11}=\left[\begin{array}{cc}-\frac{1}{T_{\mathrm{\&alpha;}}}& 0\\ \frac{1}{T_d}& -\frac{1}{T_d}\end{array}\right],A_{12}=\left[\begin{array}{c}\frac{K_{\mathrm{\&alpha;}}}{T_{\mathrm{\&alpha;}}}\\ 0\end{array}\right],$ A ₂₁＝[0 0]， $A_{22}=\&lsqb;-\frac{1}{T_R}\&rsqb;,B_1=\left[\begin{array}{c}0\\ 0\end{array}\right],B_2=\&lsqb;-\frac{K_R}{T_R}\&rsqb;.$

If (A, B) is completely controlled, therefore (A ₁₁, A ₁₂) completely controlled, and given expectation limit is p=[λ ₁, λ ₂, λ ₃], for A ₁₁get p ₁=[λ ₁, λ ₂], know thus system (A ₁₁, A ₁₂), state feedback matrix K=place (A _11,a ₁₂, p ₁), wherein, place is robust features structure POLE PLACEMENT USING function.Therefore constant matrices C=[K, I _l].

3) given stability criteria condition: if condition | w|<a, a > 0, a has got dividing value and has set up, then exist make for all t and x ∈ B ^c(η), uncertain wind bavin hybrid power system keeps stable on sliding formwork diverter surface s (t)=0, wherein λ _min(Q) be the characteristic value of matrix Q.

4) sliding mode controller u=(CB) is designed ^-1[-CAx-CPw-ε sgn (s)-ks], wherein, sgn () is sign function, $\mathrm{sgn}\left(s\right)=\left\{\begin{array}{cc}1,& s\&GreaterEqual;0\\ 0,& s<0\end{array}\right..$

For making sliding mode controller design and convenience of calculation, make H=-(CB) ^-1(CA+kC), n=-(CB) ^-1cP, m=-(CB) ^-1ε, gets 0 < ε < 1 _,k>=10, then sliding mode controller u can abbreviation be u=Hx+nw+msgn (s).

(4) sample calculation analysis

Utilize wind bavin hybrid power system in isolated island situation to verify validity of the present invention.

Consider as leeward bavin hybrid power system simulation model

${\stackrel{\&CenterDot;}{x}}_0=A_0{x}_0+B_0{u}_0+C_{0}p$

Its state variable is

x ₀＝[ΔE _fdΔV _aΔV _fΔE' _qΔB _SVCΔB' _SVCΔα ΔV] ^T

u ₀＝[ΔV _ref]

p＝[ΔQ _L]

Structured flowchart as shown in Figure 5, wherein Q _sVCfor the reactive power provided by SVC, B _sVCfor the idle admittance of SVC, each parameter value is in table 1 and table 3:

In order to the effect of outstanding sliding formwork SVC controller, first for containing traditional SVC wind bavin system the disturbance that load or burden without work is subject to be step signal and random signal acting in conjunction time, the transient response of each idle variable of wind bavin mixing Iarge-scale system, as shown in Fig. 6 (a)-Fig. 6 (d).In order to prove that controller has robustness under model condition of uncertainty, carrying out emulation respectively to the wind bavin hybrid power system under three kinds of different blower fan permeabilities proves.

Situation (1): in wind-Chai hybrid system I, fan capacity is 150kW, diesel capacity is 150kW, and load capacity is the mixing Iarge-scale system of 250kW, and now blower fan installed capacity is 3:5 with the ratio of load capacity.Its concrete data are in table 2, and the simulation waveform of this system when step load perturbation action is as shown in Fig. 7 (a)-Fig. 7 (d).The simulation waveform of this system when the fluctuation of blower fan power output step and random load perturbation action is as shown in Fig. 8 (a)-Fig. 8 (d).

Situation (2): in wind-Chai hybrid system II, fan capacity is 100kW, diesel capacity is 150kW, and load capacity is the mixing Iarge-scale system of 200kW, and now blower fan installed capacity is 1:2 with the ratio of load capacity.Its concrete data are in table 2, and the simulation waveform of this system when step load perturbation action is as shown in Fig. 9 (a)-Fig. 9 (d).The simulation waveform of this system when the fluctuation of blower fan power output step and random load perturbation action is as shown in Figure 10 (a)-Figure 10 (d).

Situation (3): in wind-Chai hybrid system III, fan capacity is 150kW, diesel capacity is 150kW, and load capacity is the mixing Iarge-scale system of 250kW, and now blower fan installed capacity is 1:3 with the ratio of load capacity.Its concrete data are in table 2, and the simulation waveform of this system when step load perturbation action is as shown in Figure 11 (a)-Figure 11 (d).The simulation waveform of this system when the fluctuation of blower fan power output step and random load perturbation action is as shown in Figure 12 (a)-Figure 12 (d).

As can be seen from the simulation result of Fig. 6 (a)-12 (d), for the wind bavin hybrid system that three kinds under different blower fan permeability are different, under same blower fan power output is the condition of step signal, no matter load or burden without work is step disturbance signal or random disturbance signal, SVC sliding mode controller of the present invention, all than the strong robustness of traditional simple adoption rate amplifier control SVC, also has better effect in the transient stability improving electric power system.

Table 1 wind-Chai system data

The parameter of table 2 different capabilities leeward-Chai system

System parameters	Wind-Chai system I	Wind-Chai system II	Wind-Chai system III
				K 1	0.15	0.15	0.15
K 2	0.793232	0.7589468	0.673608
				K 3	6.22143	5.952524	5.2832
K 4	-7.358895	-7.823439	-8.906
				K 5	0.126043	0.1067734	0.052182
K 6	1.478	1.3364	0.996
				K 7	1.0	1.0	1.0
K 8	0.4916	0.4916	0.4916
				K 9	0.0005	00005.	0.0005
K R	592.92	718.75	1121.70
				K V	0.6667	0.6667	0.6667
K α	0.446423	0.403279	0.30056
				T V	0.000106	0.000106	0.000106

The data of table 3 excitation system and SVC

Claims (6)

1. a sliding formwork Static Var Compensator method for building up for isolated wind bavin hybrid power system, is characterized in that, comprise the following steps:

(1) the closed loop states equation of traditional SVC Mathematical Modeling is set up:

$\left\{\begin{array}{c}\stackrel{\&CenterDot;}{x}=Ax+Bu+Pw\\ y=C_{0}x\end{array}\right.$

Wherein, x=[Δ B _sVCb' _sVCΔ α] ^t, u is control variables, sytem matrix $A=\left[\begin{array}{ccc}-\frac{1}{T_{\mathrm{\&alpha;}}}& 0& \frac{K_{\mathrm{\&alpha;}}}{T_{\mathrm{\&alpha;}}}\\ \frac{1}{T_d}& -\frac{1}{T_d}& 0\\ 0& 0& -\frac{1}{T_R}\end{array}\right],$ Input matrix $B=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Perturbation matrix $P=\left[\begin{array}{c}0\\ 0\\ \frac{K_R}{T_R}\end{array}\right],$ Output matrix C ₀=[0 1 0], w=Δ V _ref-Δ V, Δ V _reffor the reference value of voltage deviation amount, Δ V is the actual value of voltage deviation, K _rfor the gain of Reactive-power control device, T _rfor the time constant of adjuster, K _αfor IGBT group gain, T _αfor IGBT group time of delay, T _dfor the average dead time time of zero crossing place SVC in three-phase system, B' _sVCfor the idle susceptance of SVC, Δ B _sVCfor the variable quantity of idle susceptance, Δ α is the variable quantity at IGBT group angle;

(2) according to the state equation design sliding formwork diverter surface s=Cx that step (1) is set up, wherein C is constant matrices;

(3) the sliding formwork diverter surface s that step (2) is set up is utilized, the stability criteria condition of given electric power system, design sliding mode controller u=(CB) ^-1[-CAx-CPw-ε sgn (s)-ks], wherein, constant ε, k are velocity of approach, ε > 0, k > 0;

(4) sliding mode controller u is added in SVC control system as additional controller, sliding formwork the control of reactive power compensating is carried out to electric power system.

2. the sliding formwork Static Var Compensator method for building up of a kind of isolated wind bavin hybrid power system according to claim 1, it is characterized in that, in described step (1), (A, B) is completely controlled.

3. the sliding formwork Static Var Compensator method for building up of a kind of isolated wind bavin hybrid power system according to claim 1, it is characterized in that, described step (2) comprises the following steps:

(2-1) A, B piecemeal is obtained $A=\left[\begin{array}{cc}{A}_{11}& A_{12}\\ A_{21}& A_{22}\end{array}\right],$ $B=\left[\begin{array}{c}{B}_1\\ B_2\end{array}\right],$ Wherein $A_{11}=\left[\begin{array}{cc}-\frac{1}{T_{\mathrm{\&alpha;}}}& 0\\ \frac{1}{T_d}& -\frac{1}{T_d}\end{array}\right],$ $A_{12}=\left[\begin{array}{c}\frac{K_{\mathrm{\&alpha;}}}{T_{\mathrm{\&alpha;}}}\\ 0\end{array}\right],$ A ₂₁＝[0 0]， $A_{22}=\&lsqb;-\frac{1}{T_R}\&rsqb;,$ $B_1=\left[\begin{array}{c}0\\ 0\end{array}\right],$ $B_2=\&lsqb;-\frac{K_R}{T_R}\&rsqb;;$

(2-2) A is calculated ₁₁limit p ₁=[λ ₁, λ ₂];

(2-3) computing mode feedback matrix K=place (A ₁₁, A ₁₂, p ₁), wherein, place is robust features structure POLE PLACEMENT USING function;

(2-4) C=[K, I is got _l], set up sliding formwork diverter surface s=Cx, wherein, I _lfor unit battle array.

4. the sliding formwork Static Var Compensator method for building up of a kind of isolated wind bavin hybrid power system according to claim 1, it is characterized in that, in described step (4), be u=Hx+nw+msgn (s) by the sliding mode controller abbreviation of design, wherein H=-(CB) ^-1(CA+kC), n=-(CB) ^-1cP, m=-(CB) ^-1ε, sgn () are sign function, $\mathrm{sgn}\left(s\right)=\left\{\begin{array}{cc}1,& s\&GreaterEqual;0\\ 0,& s<0\end{array}\right..$

5. the sliding formwork Static Var Compensator method for building up of a kind of isolated wind bavin hybrid power system according to claim 1, it is characterized in that, in described step (3), the given stability criteria condition of electric power system is: if condition | w|<a sets up, wherein a has got dividing value, then exist make for all t and x ∈ B ^c(η), electric power system keeps stable on sliding formwork diverter surface s (t)=0, wherein B ^c(η) be take x=0 as the centre of sphere, the benefit of the η closed sphere B (η) that is radius, q is positive definite matrix, λ _min(Q) be the characteristic value of matrix Q.

6. the sliding formwork Static Var Compensator method for building up of a kind of isolated wind bavin hybrid power system according to claim 1, is characterized in that, in described step (4), gets 0 < ε < 1, k >=10.