CN102790401A - Method for inhibiting fluctuation of random power of alternative-current junctor - Google Patents

Abstract

The invention provides a method for inhibiting fluctuation of random power of an alternative-current junctor, which is characterized by changing the power of a liner circuit through establishing a direct-current modulation controller so as to transfer the fluctuation of the random power on the alternative-current junctor. The method comprises following steps that step S1: a design target of the direct-current power modulation controller is determined according to a set transferring ratio r, wherein the transferring ratio r is a previously-set ratio for the direct-current junctor to share the fluctuation of the random power on the alternative-current junctor according to needs, sigma () is a standard difference function of a signal; sigma (PT) is a standard difference of the alternative-current junctor power PT; and sigma (PDC) is a standard difference of the direct-current circuit power PDC; and step 2: the direct-current power modulation controller comprises a measurement link, a blocking link and a gain link, the modulation signal is the power PT of the alternative-current junctor, and a model of the direct-current power modulation controller is determined according to the time constant Tmes and tw of the measurement link and the blocking link as well as the control gain KDC of the gain link and the modulation signal PT. The method has an important significance for guaranteeing the safe and stable operation of an extreme high voltage synchronization power grid.

Description

A kind of alternating current interconnection method of power fluctuation at random that suppresses

Technical field

The present invention relates to field of power, be specifically related to a kind of alternating current interconnection method of power fluctuation at random that suppresses.

Background technology

In January, 2009, Changzhi-Nanyang-Jingmen extra-high-voltage alternating current experiment and demonstration engineering formally puts into operation, and this circuit connects North China, Central China two big regional power grids, has formed the maximum ac synchronous electrical network of China.In December, 2011, extra-high-voltage alternating current experiment and demonstration engineering extension project puts into operation, and has realized the target of 5,000,000 kilowatts of extra-high voltage AC circuit transmission capacities.

The extra-high voltage grid first stage of construction; Grid structure is weak; North China electrical network and Central China Power Grid are only interconnected through the ultra high voltage interconnection, owing to Power Exchange and system loading amplitude of variation between net are bigger, have the power fluctuation at random of certain amplitude when normally moving on the ultra high voltage interconnection.Generally speaking, the interconnection tie power fluctuation amplitude is in 300MW, and power fluctuation can be bigger under unfavorable conditions.Bigger power fluctuation not only possibly destroy the static stability of electrical network, and its voltage that causes fluctuation also can cause system's pressure regulation difficulty, the safe operation of direct threats extra-high voltage grid and equipment.Therefore, reduce and suppress power fluctuation at random on the ultra high voltage interconnection to be the major issue that the current scheduling operation needs to be resolved hurrily, significant to the safe and stable operation that ensures North China-Central China synchronised grids.

(Automatic Generation Control AGC) is the conventional means of alternating current interconnection power control in the practical power systems to automatic generation control at present.There is document to combine extra-high-voltage alternating current experiment and demonstration engineering to propose ultra high voltage interconnected network interconnection power control strategy, and providing relevant evaluating index.It is that Central China Power Grid has proposed a kind of AGC control strategy that province is coordinated of netting that document is arranged, and also has the AGC control strategy of document NORTEL net to China to improve, and its purpose all is a control ultra high voltage interconnection tie power fluctuation.Can reduce the power fluctuation of interconnection to a certain extent through the control strategy that improves AGC; Yet the control effect of AGC not only receives the influence of frequency departure coefficient; Also depend on the performance such as quantity and start-stop time, creep speed, spinning reserve capacity of frequency modulation unit; Suppress effect in order to obtain better power fluctuation, need to drop into more high-performance AGC unit, this must influence the economy of operation.

To suppressing the alternating current interconnection deficiency of the prior art of power fluctuation at random; The present invention through direct current power modulation fast Absorption or compensate its connect the surplus or the vacancy power of AC system; Thereby the power fluctuation at random on the inhibition alternating current interconnection is compared with AGC and to be had the advantages that response speed is fast, the amplitude of accommodation is big.

Summary of the invention

Deficiency to prior art; The present invention provides a kind of alternating current interconnection method of power fluctuation at random that suppresses; Help improving static stability, reactive voltage regulating power and the circuit conveying capacity of system, significant to the safe and stable operation that ensures the ultra high voltage synchronised grids.The present invention provides a kind of alternating current interconnection method of power fluctuation at random that suppresses, and changes DC line power to shift the power fluctuation at random on the alternating current interconnection through setting up the direct current modulation controller, and said method comprises:

Step S1 confirms the design object of said direct current power modulation controller according to the transfer ratio r that sets;

Said transfer ratio r shares the ratio of the power fluctuation at random on the alternating current interconnection for predefined DC link as required,

$r=\frac{\mathrm{\σ}\left(P_{\mathrm{DC}}\right)}{\mathrm{\σ}\left(P_T\right)+\mathrm{\σ}\left(P_{\mathrm{DC}}\right)}$

Wherein σ () is the standard deviation function of signal; σ (P _T) be the alternating current interconnection power P _TStandard deviation; σ (P _DC) be the DC line power P _DCStandard deviation;

Step S2, said direct current power modulation controller comprise measurement links, separated straight link and gain link, and modulation signal is the power P of alternating current interconnection _T, according to measurement links with at a distance from straight link time constant T _MesAnd τ _wAnd the ride gain K of gain link _DCWith modulation signal P _TConfirm the model of said direct current power modulation controller.

In first kind of preferred embodiment provided by the invention: among the said step S1, confirm that according to the transfer ratio r that sets the design object of alternating-current controller is:

$\underset{K_{\mathrm{DC}}}{\min J}=|(1-r)\·\mathrm{\σ}\left(P_{\mathrm{DC}}\right)-r\·\mathrm{\σ}\left(P_T\right)|$

Wherein, K _DCBe the gain of said dc controller, J is the controller performance index, and the standard deviation function σ () of signal is:

$\mathrm{\σ}\left(x\right)=\sqrt{\frac{1}{T}{\∫}_0^T{[x\left(t\right)-\mathrm{\μ}\left(x\right)]}^2\mathrm{dt}}$

X (t) is a measuring-signal; T is a simulation time; μ (x) is the mean value function

of signal x

In second kind of preferred embodiment provided by the invention: among the said step S2, the transfer function of said measurement links does

Said is to approach the component of direct current in elimination or the reduction measuring-signal at a distance from straight link purpose, and transfer function does

The ride gain K of said gain link _DCGain K for said dc controller definite among the said step S1 _DC

In the third preferred embodiment provided by the invention: said method also comprises:

Step S3 adopts improved particle cluster algorithm to optimize the dc controller parameter.

In the 4th kind of preferred embodiment provided by the invention: the method that adopts improved example algorithm to optimize the parameter of dc controller among the said step S3 is:

The optimal solution that each particle searches through tracking particle and population is at present upgraded speed and the position of oneself, and the particle position parameter is controller gain K _DC, the fitness value of particle is controller performance index J;

In each iteration, each particle upgrades oneself through following the tracks of 4 extreme values, and said 4 extreme values comprise the desired positions P that particle i searches at present _Besti=(P _Bi1, P _Bi2, P _BiD) and the most bad position P _Worsti=(P _Wi1, P _Wi2..., P _WiD); The desired positions G that whole population searches at present _Best=(G _B1, G _B2..., G _BD) and the most bad position G _Worst=(G _W1, G _W2..., G _WD), calculating particle's velocity and position convergence condition is that iteration reaches given maximum step number or the disturbance number of times reaches set-point;

(K +1) th iteration of the i-th particle of d-dimensional velocity

and position The update equation is:

$\left\{\begin{array}{c}{v}_{\mathrm{id}}^{(k+1)}=\mathrm{\&omega;}\&CenterDot;v_{\mathrm{id}}^{\left(k\right)}+{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="HDA00001922814600013.png,HDA00001922814600022.png"\; state="\{\{state\}\}">c</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="r"\; filenames="HDA00001922814600013.png,HDA00001922814600022.png"\; state="\{\{state\}\}">r</figure-callout>}}_1\&CenterDot;(P_{\mathrm{Bid}}-u_{\mathrm{id}}^{\left(k\right)})+c_2\&CenterDot;r_2\&CenterDot;(G_{\mathrm{Bd}}-u_{\mathrm{id}}^{\left(k\right)})+c_3\&CenterDot;r_3\&CenterDot;(u_{\mathrm{id}}^{\left(k\right)}-P_{\mathrm{Wid}})+\\ c_4\&CenterDot;r_4\&CenterDot;(u_{\mathrm{id}}^{\left(k\right)}-G_{\mathrm{Wd}})\\ \begin{array}{cc}{v}_{\mathrm{id}}^{(k+1)}=v_{d\max },& v_{\mathrm{id}}^{(k+1)}>v_{d\max }\end{array}\\ \begin{array}{cc}{v}_{\mathrm{id}}^{(k+1)}=-v_{d\max },& v_{\mathrm{id}}^{(k+1)}<-v_{d\max }\end{array}\end{array}\right.$

$\left\{\begin{array}{c}{u}_{\mathrm{id}}^{(k+1)}=u_{\mathrm{id}}^{\left(k\right)}+v_{\mathrm{id}}^{(k+1)}\\ \begin{array}{cc}{u}_{\mathrm{id}}^{(k+1)}=u_{d\max },& u_d>u_{d\max }\end{array}\\ \begin{array}{cc}{u}_{\mathrm{id}}^{(k+1)}=u_{d\min },& u_d<u_{d\min }\end{array}\end{array}\right.$

Wherein, r ₁, r ₂, r ₃And r ₄Random number for interval [0,1]; u _DminAnd u _DmaxPosition lower limit and higher limit for particle d dimension; v _DmaxMaximal rate limit value for particle d dimension is taken as search volume (u _Dmax-u _Dmin) 50%; c ₁, c ₂, c ₃And c ₄Be accelerated factor; ω is the inertia weight factor.

In the 5th kind of preferred embodiment provided by the invention: introduce the possibility that mutation operation and disturbance operation minimizing population are absorbed in local extremum among the said step S3, the enlightenment that the accuracy that adopts the strategy that dynamically changes inertia weight to strengthen the direction of search obtains.

Automatic generation control is to suppress the alternating current interconnection conventional means of power fluctuation at random in the practical power systems at present; But the control effect of AGC not only receives the influence of frequency departure coefficient; Also depend on the performance such as quantity and start-stop time, creep speed, spinning reserve capacity of frequency modulation unit; Suppress effect in order to obtain better power fluctuation, need to drop into more high-performance AGC unit, this must influence the economy of operation.The present invention has utilized the characteristics that the HVDC transmission system response speed is fast, the amplitude of accommodation is big, can effectively suppress the power fluctuation at random on the alternating current interconnection through the direct current power modulation.The present invention can be according to prior given transfer ratio; Completely or partially the power fluctuation at random on the alternating current interconnection is transferred on the DC line; Help improving static stability, reactive voltage regulating power and the circuit conveying capacity of AC system, significant to the safe and stable operation that ensures the ultra high voltage synchronised grids.

Description of drawings

Fig. 1 is three regional interconnected systems illustratons of model;

Fig. 2 is a kind of alternating current interconnection method flow diagram of power fluctuation at random that suppresses provided by the invention;

Fig. 3 is a kind of direct current power modulation pattern structure chart provided by the invention;

Fig. 4 is the ultra high voltage interconnection simulation curve of power fluctuation at random among the embodiment one provided by the invention;

Fig. 5 is gain K different among the embodiment one provided by the invention _DCCorresponding ultra high voltage interconnection tie power fluctuation amplitude;

Fig. 6 is gain K different among the embodiment one provided by the invention _DCCorresponding direct current power fluctuation amplitude;

Fig. 7 is gain K different among the embodiment one provided by the invention _DCCorresponding system frequency fluctuation amplitude;

Fig. 8 is that controller parameter provided by the invention is optimized flow chart;

Fig. 9 is that transfer ratio is 50% o'clock power fluctuation amplitude contrast among the embodiment one provided by the invention.

Embodiment

Do further to specify below in conjunction with the accompanying drawing specific embodiments of the invention.

The present invention proposes a kind of method that suppresses alternating current interconnection tie power fluctuation; Be illustrated in figure 1 as three regional interconnected systems illustratons of model; Three zones are respectively the A of system, system B and the C of system; System A and the B of system are interconnected through weak alternating current interconnection, and system A and the C of system are interconnected through DC link, can suppress the power fluctuation at random on the alternating current interconnection.Through gathering the power signal on the alternating current interconnection, the effect of process direct current modulation controller obtains the direct current power adjustment amount, thereby changes DC line power to shift the power fluctuation at random on the alternating current interconnection.

A kind of method that suppresses alternating current interconnection tie power fluctuation provided by the invention may further comprise the steps:

Step S1 confirms the design object of direct current power modulation controller according to the transfer ratio r that sets.

This transfer ratio r shares the ratio of the power fluctuation at random on the alternating current interconnection for predefined DC link as required,

$r=\frac{\mathrm{\&sigma;}\left(P_{\mathrm{DC}}\right)}{\mathrm{\&sigma;}\left(P_T\right)+\mathrm{\&sigma;}\left(P_{\mathrm{DC}}\right)}$

Wherein σ () is the standard deviation function of signal; σ (P _T) be the alternating current interconnection power P _TStandard deviation; σ (P _DC) be the DC line power P _DCStandard deviation.

Step S2, direct current power modulation controller comprise measurement links, separated straight link and gain link, and modulation signal is got the power P of alternating current interconnection _T, according to measurement links with at a distance from straight link time constant T _MesAnd τ _wAnd the ride gain K of gain link _DCWith modulation signal P _TConfirm the model of this direct current power modulation controller.

Among the above-mentioned steps S1, confirm that according to the transfer ratio r that sets the design object of alternating-current controller is:

$\underset{K_{\mathrm{DC}}}{\min J}=|(1-r)\&CenterDot;\mathrm{\&sigma;}\left(P_{\mathrm{DC}}\right)-r\&CenterDot;\mathrm{\&sigma;}\left(P_T\right)|$

Wherein, the transfer function of gain link is K _DC, J is the controller performance index, the standard deviation function σ () of signal is:

$\mathrm{\&sigma;}\left(x\right)=\sqrt{\frac{1}{T}{\&Integral;}_0^T{[x\left(t\right)-\mathrm{\&mu;}\left(x\right)]}^2\mathrm{dt}}$

X (t) is a measuring-signal; T is a simulation time; μ (x) is the mean value function of signal x

Among the above-mentioned steps S2; The direct current power modulation controller comprises measurement links, separated straight link and gain link; Wherein, The transfer function of measurement links is elimination or reduces the component that approaches direct current in the measuring-signal at a distance from straight link purpose for

; Have bigger time constant, transfer function is

Embodiment one:

Embodiment one provided by the invention is an example with North China-Central China networking big mode of summer in 2012, explains through the modulation direct current power and can realize suppressing to exchange getting in touch with power fluctuation at random.Through ultra high voltage interconnection transmission power 5000MW, AGC adopts permanent power control mode to Central China Power Grid to the North China electrical network under this mode.

Step S1': the design object of confirming the direct current power modulation controller according to the transfer ratio r that sets.

This execution mode is to realize that transfer ratio r=50% is an example; Realize that promptly power fluctuation shares on alternating current interconnection and DC link in 50% ratio jointly, the design of Controller target is

so

Step S2': according to measurement links with at a distance from straight link time constant T _MesAnd τ _wAnd the ride gain K of gain link _DCWith modulation signal P _TConfirm the model of this direct current power modulation controller.Wherein, the transfer function of measurement links does

Time constant T _Mes=0.01s; At a distance from straight link transfer function do

Purpose is elimination or reduces the component that approaches direct current in the measuring-signal, has bigger time constant, timeconstant _w=10s; The transfer function of gain link is the definite K of step S1 ' _DC

Be illustrated in figure 3 as electric system simulation model provided by the invention.The electric system simulation model could be used the formula mistake! Do not find Reference source.Shown non-linear differential-algebraic equation is described:

$\left\{\begin{array}{c}\stackrel{\&CenterDot;}{x}=f(x,u)\\ y=g(x,u)\end{array}\right.$

In the formula, x is a state vector; U is an input vector; Y is an output vector; F, g are the nonlinear function vector.Algebraic equation has been described the grid characteristic, differential equation the dynamic characteristic of system element.The cycle of power fluctuation arrived several minutes at tens of seconds to the interconnection of this paper research at random; Therefore the differential equation is except comprising electric power system electromechanical transient model; Also need consider the medium-term and long-term dynamic model of thermoelectricity, water power and nuclear power dynamical system and the AGC model of interconnection; Considered the effect of AGC in the system dynamic model shown in Figure 3, wherein B _AAnd B _BBe respectively the frequency departure coefficient of A of system and B; When its value is zero for exchanging power control mode (flat tie-line control surely; FTC), when value during for nonzero value be order wire frequency Deviation Control pattern (tie line bias frequency control, TBC); R _AAnd R _BBe respectively the generator difference coefficient of the A of system, system B.Simulation model has also been considered the medium-term and long-term dynamic model of thermoelectricity, water power and nuclear power dynamical system and the AGC model of extra-high-voltage alternating current interconnection except comprising electric power system electromechanical transient model.Emulation tool adopts electric power system full dynamic simulation software.Through applying the random load disturbance, on the ultra high voltage interconnection, form power fluctuation at random as shown in Figure 4.

Table 1 has provided direct current modulation controller gain K _DCVariation to control effect influence.Can see that DC line has not only been born the power amount of unbalance that shifts on the ultra high voltage interconnection, and bear the power amount of unbalance of system frequency fluctuation reflection.

Table 1 direct current modulation controller gain K _DCSensitivity analysis table to the control effect

On the one hand, along with controller gain K _DCIncrease, ultra high voltage interconnection power standard difference σ (P _T) constantly reduce, and direct current power standard deviation sigma (P _DC) then constantly increase, this shows through the direct current modulation has transferred to the power fluctuation on the ultra high voltage interconnection on the direct current.The ultra high voltage interconnection tie power fluctuation amplitude that different controller gains are corresponding and direct current power fluctuation amplitude such as Fig. 5 and shown in Figure 6.

On the other hand, along with K _DCIncrease, the standard deviation of system frequency fluctuation is also in continuous minimizing, this shows the effect through the direct current modulation, the power amount of unbalance of system frequency reflection has also been transferred on the direct current.The system frequency fluctuation amplitude that different controller gains are corresponding is as shown in Figure 7.

Preferably, provided by the invention a kind of suppress alternating current interconnection at random the method for power fluctuation also comprise:

Step S3: adopt improved particle cluster algorithm to optimize the dc controller parameter.

A kind of method flow diagram that adopts improved particle cluster algorithm to optimize the dc controller parameter provided by the invention is as shown in Figure 8; Wherein, I representes i particle in the population; Each particle is speed and the position that optimal solution that particle and population search is at present upgraded oneself through following the tracks of extreme value, and the particle position parameter is exactly controller gain K _DC, the fitness value of particle is exactly controller performance index J, and calculating particle's velocity and position convergence condition is that iteration reaches given maximum step number, or the disturbance number of times reaches set-point.

Each particle is speed and the position that optimal solution that particle and population search is at present upgraded oneself through following the tracks of 2 extreme values in the basic particle cluster algorithm; For the historical search experience that makes full use of particle strengthens the global search performance of population, the inferior solution that the present invention searches particle and population is at present also introduced the renewal equation of particle.If the search volume is the D dimension, population is N, and i particle position is u in the population _i=(u _I1, u _I2..., u _ID), i particle's velocity is v _i=(v _I1, v _I2..., v _ID), each particle position all is potential separating.In each iteration, each particle upgrades oneself through tracking 4 " extreme values ", i.e. the desired positions P that searches at present of particle i _Besti=(P _Bi1, P _Bi2..., P _BiD) and the most bad position P _Worsti=(P _Wi1, P _Wi2..., P _WiD); The desired positions G that whole population searches at present _Best=(G _B1, G _B2..., G _BD) and the most bad position G _Worst=(G _W1, G _W2..., G _WD).(K +1) th iteration of the i-th particle of d-dimensional velocity

and position

using the update equation is:

$\left\{\begin{array}{c}{v}_{\mathrm{id}}^{(k+1)}=\mathrm{\&omega;}\&CenterDot;v_{\mathrm{id}}^{\left(k\right)}+{\mathrm{<figure-callout\; id="1"\; label="c"\; filenames="HDA00001922814600013.png,HDA00001922814600022.png"\; state="\{\{state\}\}">c</figure-callout>}}_1\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="r"\; filenames="HDA00001922814600013.png,HDA00001922814600022.png"\; state="\{\{state\}\}">r</figure-callout>}}_1\&CenterDot;(P_{\mathrm{Bid}}-u_{\mathrm{id}}^{\left(k\right)})+c_2\&CenterDot;r_2\&CenterDot;(G_{\mathrm{Bd}}-u_{\mathrm{id}}^{\left(k\right)})+c_3\&CenterDot;r_3\&CenterDot;(u_{\mathrm{id}}^{\left(k\right)}-P_{\mathrm{Wid}})+\\ c_4\&CenterDot;r_4\&CenterDot;(u_{\mathrm{id}}^{\left(k\right)}-G_{\mathrm{Wd}})\\ \begin{array}{cc}{v}_{\mathrm{id}}^{(k+1)}=v_{d\max },& v_{\mathrm{id}}^{(k+1)}>v_{d\max }\end{array}\\ \begin{array}{cc}{v}_{\mathrm{id}}^{(k+1)}=-v_{d\max },& v_{\mathrm{id}}^{(k+1)}<-v_{d\max }\end{array}\end{array}\right.$

$\left\{\begin{array}{c}{u}_{\mathrm{id}}^{(k+1)}=u_{\mathrm{id}}^{\left(k\right)}+v_{\mathrm{id}}^{(k+1)}\\ \begin{array}{cc}{u}_{\mathrm{id}}^{(k+1)}=u_{d\max },& u_d>u_{d\max }\end{array}\\ \begin{array}{cc}{u}_{\mathrm{id}}^{(k+1)}=u_{d\min },& u_d<u_{d\min }\end{array}\end{array}\right.$

In the formula: r ₁, r ₂, r ₃And r ₄Random number for interval [0,1]; u _DminAnd u _DmaxPosition lower limit and higher limit for particle d dimension; v _DmaxMaximal rate limit value for particle d dimension can be taken as search volume (u _Dmax-u _Dmin) 50%; c ₁, c ₂, c ₃And c ₄Be accelerated factor; ω is the inertia weight factor, and adopts the strategy that dynamically changes inertia weight, makes gaining enlightenment property of the accuracy reinforcement of the direction of search.

In basic PSO algorithm, with the increase of iterations, the diversity of population can constantly reduce, and is prone to produce " precocity " phenomenon.This paper introduces mutation operation and disturbance operation and has reduced the possibility that population is absorbed in local extremum.

Concrete, among the embodiment one, when transfer ratio r=50%, calculating optimum gain through improved particle cluster algorithm is K _DC=0.53.At this moment, the power fluctuation standard deviation sigma (P of ultra high voltage interconnection and direct current _T)=σ (P _DC)=157.4MW, frequency fluctuation standard deviation sigma (Δ f)=24.1 * 10 ^-3Hz, controller performance index J=0 means that DC line and ultra high voltage interconnection respectively shared 50% power fluctuation, its power fluctuation amplitude with adopt direct current modulation (K _DC=0) the situation contrast the time is as shown in Figure 9.

Should be noted that at last: above embodiment is only in order to technical scheme of the present invention to be described but not to its restriction; Although the present invention has been carried out detailed explanation with reference to the foregoing description; Under the those of ordinary skill in field be to be understood that: still can specific embodiments of the invention make amendment or be equal to replacement; And do not break away from any modification of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of the claim scope of the present invention.

Claims (6)

1. one kind is suppressed the alternating current interconnection method of power fluctuation at random, it is characterized in that, said method changes DC line power to shift the power fluctuation at random on the alternating current interconnection through setting up the direct current modulation controller, and said method comprises:

Step S1 confirms the design object of said direct current power modulation controller according to the transfer ratio r that sets;

Said transfer ratio r shares the ratio of the power fluctuation at random on the alternating current interconnection for predefined DC link as required,

$r=\frac{\mathrm{\&sigma;}\left(P_{\mathrm{DC}}\right)}{\mathrm{\&sigma;}\left(P_T\right)+\mathrm{\&sigma;}\left(P_{\mathrm{DC}}\right)}$

Wherein σ () is the standard deviation function of signal; σ (P _T) be the alternating current interconnection power P _TStandard deviation; σ (P _DC) be the DC line power P _DCStandard deviation;

Step S2, said direct current power modulation controller comprise measurement links, separated straight link and gain link, and modulation signal is the power P of alternating current interconnection _T, according to measurement links with at a distance from straight link time constant T _MesAnd τ _wAnd the ride gain K of gain link _DCWith modulation signal P _TConfirm the model of said direct current power modulation controller.

2. the method for claim 1 is characterized in that, among the said step S1, confirms that according to the transfer ratio r that sets the design object of alternating-current controller is:

$\underset{K_{\mathrm{DC}}}{\min J}=|(1-r)\&CenterDot;\mathrm{\&sigma;}\left(P_{\mathrm{DC}}\right)-r\&CenterDot;\mathrm{\&sigma;}\left(P_T\right)|$

Wherein, K _DCBe the gain of said dc controller, J is the performance index of said dc controller, and the standard deviation function σ () of signal is:

$\mathrm{\&sigma;}\left(x\right)=\sqrt{\frac{1}{T}{\&Integral;}_0^T{[x\left(t\right)-\mathrm{\&mu;}\left(x\right)]}^2\mathrm{dt}}$

X (t) is a measuring-signal; T is a simulation time; μ (x) is the mean value function

of signal x

3. method as claimed in claim 2 is characterized in that, among the said step S2, the transfer function of said measurement links does

Said is to approach the component of direct current in elimination or the reduction measuring-signal at a distance from straight link purpose, and transfer function does The ride gain K of said gain link _DCGain K for said dc controller definite among the said step S1 _DC

4. the method for claim 1 is characterized in that, said method also comprises:

Step S3 adopts improved particle cluster algorithm to optimize the dc controller parameter.

5. method as claimed in claim 4 is characterized in that, the method that adopts improved example algorithm to optimize the parameter of dc controller among the said step S3 is:

The optimal solution that each particle searches through tracking particle and population is at present upgraded speed and the position of oneself, and the particle position parameter is controller gain K _DC, the fitness value of particle is controller performance index J;

In each iteration, each particle upgrades oneself through following the tracks of 4 extreme values, and said 4 extreme values comprise the desired positions P that particle i searches at present _Besti=(P _Bi1, P _Bi2..., P _BiD) and the most bad position P _Worsti=(P _Wi1, P _Wi2..., P _WiD); The desired positions G that whole population searches at present _Best=(G _B1, G _B2..., G _BD) and the most bad position G _Worst=(G _W1, G _W2..., G _WD), calculating particle's velocity and position convergence condition is that iteration reaches given maximum step number or the disturbance number of times reaches set-point;

(K +1) th iteration of the i-th particle of d-dimensional velocity

and position

The update equation is:

$\left\{\begin{array}{c}{v}_{\mathrm{id}}^{(k+1)}=\mathrm{\&omega;}\&CenterDot;v_{\mathrm{id}}^{\left(k\right)}+c_1\&CenterDot;r_1\&CenterDot;(P_{\mathrm{Bid}}-u_{\mathrm{id}}^{\left(k\right)})+c_2\&CenterDot;r_2\&CenterDot;(G_{\mathrm{Bd}}-u_{\mathrm{id}}^{\left(k\right)})+c_3\&CenterDot;r_3\&CenterDot;(u_{\mathrm{id}}^{\left(k\right)}-P_{\mathrm{Wid}})+\\ c_4\&CenterDot;r_4\&CenterDot;(u_{\mathrm{id}}^{\left(k\right)}-G_{\mathrm{Wd}})\\ \begin{array}{cc}{v}_{\mathrm{id}}^{(k+1)}=v_{d\max },& v_{\mathrm{id}}^{(k+1)}>v_{d\max }\end{array}\\ \begin{array}{cc}{v}_{\mathrm{id}}^{(k+1)}=-v_{d\max },& v_{\mathrm{id}}^{(k+1)}<-v_{d\max }\end{array}\end{array}\right.$

$\left\{\begin{array}{c}{u}_{\mathrm{id}}^{(k+1)}=u_{\mathrm{id}}^{\left(k\right)}+v_{\mathrm{id}}^{(k+1)}\\ \begin{array}{cc}{u}_{\mathrm{id}}^{(k+1)}=u_{d\max },& u_d>u_{d\max }\end{array}\\ \begin{array}{cc}{u}_{\mathrm{id}}^{(k+1)}=u_{d\min },& u_d<u_{d\min }\end{array}\end{array}\right.$

Wherein, r ₁, r ₂, r ₃And r ₄Random number for interval [0,1]; u _DminAnd u _DmaxPosition lower limit and higher limit for particle d dimension; v _DmaxMaximal rate limit value for particle d dimension is taken as search volume (u _Dmax-u _Dmin) 50%; c ₁, c ₂, c ₃And c ₄Be accelerated factor; ω is the inertia weight factor.

6. method as claimed in claim 5; It is characterized in that; Introduce the possibility that mutation operation and disturbance operation minimizing population are absorbed in local extremum among the said step S3, the enlightenment that the accuracy that adopts the strategy that dynamically changes inertia weight to strengthen the direction of search obtains.

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