CN102790401B - 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 method that suppresses alternating current interconnection random power fluctuation

Technical field

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

Background technology

In January, 2009, Changzhi-Nanyang-Jingmen UHVAC demonstration project formally puts into operation, and this connection North China, the large regional power grid in Central China two have formed the AC synchronous electrical network of China's maximum.In December, 2011, UHVAC demonstration project extension project puts into operation, and has realized the target of 5,000,000 kilowatts of extra-high voltage AC circuit transmission capacities.

Extra-high voltage grid first stage of construction, grid structure is weak, North China Power Telecommunication Network and Central China Power Grid are only interconnected by ultra high voltage interconnection, because Power Exchange and system loading amplitude of variation between net are larger, have the random power fluctuation of certain amplitude while normally moving on ultra high voltage interconnection.Generally, interconnection tie power fluctuation amplitude is in 300MW, and under unfavorable conditions, power fluctuation can be larger.Larger power fluctuation not only may destroy the static stability of electrical network, and the both end voltage fluctuation that it causes also can cause system pressure regulating difficulty, directly threatens the safe operation of extra-high voltage grid and equipment.Therefore, reduce and the random power fluctuation that suppresses on ultra high voltage interconnection is that current scheduling is moved major issue urgently to be resolved hurrily, significant to ensureing the safe and stable operation of North China-Central China synchronised grids.

Automatic generation control (Automatic Generation Control, AGC) is the conventional means that in practical power systems, alternating current interconnection power is controlled at present.There is document to propose ultra high voltage interconnected network interconnection power control strategy in conjunction with UHVAC demonstration project, and providing corresponding evaluation index.Having document is that Central China Power Grid has proposed a kind of AGC control strategy that province is coordinated of netting, and also has document to improve the AGC control strategy of North China Power Telecommunication Network, and its object is all to control ultra high voltage interconnection tie power fluctuation.By improving the control strategy of AGC, can reduce to a certain extent the power fluctuation of interconnection, yet the control effect of AGC is not only subject to the impact of frequency departure coefficient, also depend on the performances such as the quantity of frequency modulation unit and start-stop time, creep speed, spinning reserve capacity, in order to obtain better power fluctuation inhibition, need to drop into more high-performance AGC unit, this must affect the economy of operation.

For the deficiencies in the prior art that suppress alternating current interconnection random power fluctuation; the present invention absorbs fast by DC power modulation or compensates its surplus that connects AC system or vacancy power; thereby the random power fluctuation on inhibition alternating current interconnection, compare with AGC there is fast response time, feature that the amplitude of accommodation is large.

Summary of the invention

For the deficiencies in the prior art, the invention provides a kind of method that suppresses alternating current interconnection random power fluctuation, be conducive to improve static stability, reactive voltage regulating power and the circuit conveying capacity of system, significant to ensureing the safe and stable operation of ultra high voltage synchronised grids.The invention provides a kind of method that suppresses alternating current interconnection random power fluctuation, by setting up modulation controller device, change DC line power to shift the random power fluctuation on alternating current interconnection, described method comprises:

Step S1, determines the design object of described DC power modulation controller according to the transfer ratio r setting;

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

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

The standard deviation function that wherein σ () is signal; σ (P _t) be alternating current interconnection power P _tstandard deviation; σ (P _dC) be DC line power P _dCstandard deviation;

Step S2, described DC power modulation controller comprises measurement links, every straight link and gain link, the power P that modulation signal is alternating current interconnection _t, according to measurement links with every straight link time constant T _mesand τ _wand the ride gain K of gain link _dCwith modulation signal P _tdetermine the model of described DC power modulation controller.

In the first preferred embodiment provided by the invention: in described step S1, determine that according to the transfer ratio r setting 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 _dCfor the gain of described DC controller, J is 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 measuring-signal; T is simulation time; μ (x) is the mean value function of signal x

In the second preferred embodiment provided by the invention: in described step S2, the transfer function of described measurement links is

described is eliminate or reduce in measuring-signal close to the component of direct current every straight link object, and transfer function is

the ride gain K of described gain link _dCgain K for described DC controller definite in described step S1 _dC.

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

Step S3, adopts improved particle cluster algorithm to optimize 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 in described step S3 is:

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

In each iteration, each particle upgrades oneself by following the tracks of 4 extreme values, and described 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), the condition of the speed of calculating particle and position convergence is that iteration reaches given maximum step number or disturbance number of times reaches set-point;

The speed of i particle d dimension in the k+1 time iteration

and position

renewal equation be:

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

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

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 ₄for 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 in described step S3, the enlightenment that the accuracy that adopts the dynamic strategy that changes inertia weight to strengthen the direction of search obtains.

Automatic generation control is in practical power systems, to suppress the conventional means of alternating current interconnection random power fluctuation at present, but the control effect of AGC is not only subject to the impact of frequency departure coefficient, also depend on the performances such as the quantity of frequency modulation unit and start-stop time, creep speed, spinning reserve capacity, in order to obtain better power fluctuation inhibition, need to drop into more high-performance AGC unit, this must affect the economy of operation.The present invention has utilized HVDC (High Voltage Direct Current) transmission system fast response time, feature that the amplitude of accommodation is large, by DC power modulation, can effectively suppress the random power fluctuation on alternating current interconnection.The present invention can be according to prior given transfer ratio, completely or partially the random power fluctuation on alternating current interconnection is transferred in DC line, be conducive to improve static stability, reactive voltage regulating power and the circuit conveying capacity of AC system, significant to ensureing the safe and stable operation of ultra high voltage synchronised grids.

Accompanying drawing explanation

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

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

Fig. 3 is a kind of DC power modulation model structure figure provided by the invention;

Fig. 4 is the simulation curve of ultra high voltage interconnection random power fluctuation in embodiment mono-provided by the invention;

Fig. 5 is gain K different in embodiment mono-provided by the invention _dCcorresponding ultra high voltage interconnection tie power fluctuation amplitude;

Fig. 6 is gain K different in embodiment mono-provided by the invention _dCcorresponding direct current power fluctuation amplitude;

Fig. 7 is gain K different in embodiment mono-provided by the invention _dCcorresponding system frequency fluctuation amplitude;

Fig. 8 is controller parameter Optimizing Flow figure provided by the invention;

Fig. 9 is power fluctuation amplitude contrast when transfer ratio is 50% in embodiment mono-provided by the invention.

Embodiment

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described in further detail.

The present invention proposes a kind of method that suppresses alternating current interconnection tie power fluctuation, be illustrated in figure 1 three region interconnected systems illustratons of model, three regions are respectively system A, system B and system C, system A and system B are interconnected by weak alternating current interconnection, system A and system C are interconnected by DC link, can suppress the random power fluctuation on alternating current interconnection.By gathering the power signal on alternating current interconnection, the effect of process modulation controller device obtains direct current power adjustment amount, thereby changes DC line power to shift the random power fluctuation on alternating current interconnection.

A kind of method that suppresses alternating current interconnection tie power fluctuation provided by the invention, comprises the following steps:

Step S1, determines the design object of DC power modulation controller according to the transfer ratio r setting.

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

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

The standard deviation function that wherein σ () is signal; σ (P _t) be alternating current interconnection power P _tstandard deviation; σ (P _dC) be DC line power P _dCstandard deviation.

Step S2, DC power modulation controller comprises measurement links, every straight link and gain link, modulation signal is got the power P of alternating current interconnection _t, according to measurement links with every straight link time constant T _mesand τ _wand the ride gain K of gain link _dCwith modulation signal P _tdetermine the model of this DC power modulation controller.

In above-mentioned steps S1, according to the transfer ratio r setting, determine that 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 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 measuring-signal; T is simulation time; μ (x) is the mean value function of signal x

In above-mentioned steps S2, DC power modulation controller comprises measurement links, every straight link and gain link, wherein, the transfer function of measurement links is

every straight link object, be eliminate or reduce in measuring-signal close to the component of direct current, have larger time constant, transfer function is

Embodiment mono-:

It is example that embodiment mono-provided by the invention be take North China in 2012-Central China networking large mode of summer, illustrate can realize suppressing to exchange by modulation direct current power to get in touch with random power fluctuation.Under which, Central China Power Grid is to North China Power Telecommunication Network by ultra high voltage interconnection transmission power 5000MW, and AGC adopts permanent power control mode.

Step S1': the design object of determining DC power modulation controller according to the transfer ratio r setting.

Present embodiment be take and realized transfer ratio r=50% as example, realizes power fluctuation and jointly shares on alternating current interconnection and DC link in 50% ratio, and controller design object is so

Step S2': according to measurement links with every straight link time constant T _mesand τ _wand the ride gain K of gain link _dCwith modulation signal P _tdetermine the model of this DC power modulation controller.Wherein, the transfer function of measurement links is

time constant T _mes=0.01s; Every straight link transfer function, be

object is eliminate or reduce in measuring-signal close to the component of direct current, has larger time constant, timeconstantτ _w=10s; The transfer function of gain link is the definite K of step S1 ' _dC.

Be illustrated in figure 3 electric system simulation model provided by the invention.Electric system simulation model could be used 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 formula, x is state vector; U is input vector; Y is output vector; F, g is nonlinear function vector.Algebraic equation has been described grid characteristic, differential equation the dynamic characteristic of system element.The cycle of the interconnection random power fluctuation of research was at tens of seconds to several minutes herein, therefore the differential equation is except comprising electric power system electromechanical transient model, also need to consider the long term dynamics model of thermoelectricity, water power and nuclear power dynamical system and the AGC model of interconnection, the effect of AGC, wherein B in system dynamic model shown in Fig. 3, have been considered _aand B _bbe respectively the frequency departure coefficient of system A and B, when its value is zero, be to determine exchange power control pattern (flat tie-line control, FTC), when being nonzero value, value is order wire frequency Deviation Control pattern (tie line bias frequency control, TBC); R _aand R _bbe respectively the generator difference coefficient of system A, system B.Simulation model, except comprising electric power system electromechanical transient model, has also been considered the long term dynamics model of thermoelectricity, water power and nuclear power dynamical system and the AGC model of extra-high-voltage alternating current interconnection.Emulation tool adopts electric power system full dynamic simulation software.By applying random load disturbance, on ultra high voltage interconnection, form random power fluctuation as shown in Figure 4.

Table 1 has provided modulation controller device gain K _dCvariation on controlling the impact of effect.Can see, DC line has not only been born the unbalanced power amount shifting on ultra high voltage interconnection, and has born the unbalanced power amount of system frequency fluctuation reflection.

Table 1 modulation controller device gain K _dCto controlling the sensitivity analysis table of effect

On the one hand, along with controller gain K _dCincrease, the poor σ (P of ultra high voltage interconnection power standard _t) constantly reduce, and direct current power standard deviation sigma (P _dC) constantly increase, this shows by HVDC Modulation, the power fluctuation on ultra high voltage interconnection have been transferred on direct current.The ultra high voltage interconnection tie power fluctuation amplitude that different controller gains are corresponding and direct current power fluctuation amplitude are as shown in Figure 5 and 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 by HVDC Modulation, the unbalanced power amount of system frequency reflection has also been transferred on direct current.The system frequency that different controller gains are corresponding fluctuates amplitude as shown in Figure 7.

Preferably, a kind of method that suppresses alternating current interconnection random power fluctuation provided by the invention also comprises:

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

Provided by the inventionly a kind ofly adopt method flow diagram that improved particle cluster algorithm optimizes DC controller parameter as shown in Figure 8, wherein, i represents i particle in population, each particle is speed and the position that optimal solution that particle and population search is at present upgraded oneself by following the tracks of extreme value, and the location parameter of particle is exactly controller gain K _dC, the fitness value of particle is exactly controller performance index J, and the condition of the speed of calculating particle and position convergence is that iteration reaches given maximum step number, or disturbance number of times reaches set-point.

In basic particle cluster algorithm, each particle is speed and the position that optimal solution that particle and population search is at present upgraded oneself by following the tracks of 2 extreme values, in order to make full use of the historical search experience of particle, strengthen the global search performance of population, the inferior solution that the present invention searches particle and population at present is also introduced the renewal equation of particle.If search volume is D dimension, population is N, and in population, the position of i particle is u _i=(u _i1, u _i2..., u _iD), the speed of i particle is v _i=(v _i1, v _i2..., v _iD), the position of each particle is a potential solution.In each iteration, each particle upgrades oneself, the desired positions P that particle i searches at present by following the tracks of 4 " extreme values " _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).The speed of i particle d dimension in the k+1 time iteration and position

the renewal equation adopting 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 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 ₄for accelerated factor; ω is the inertia weight factor, and adopts the strategy that dynamically changes inertia weight, and the gaining enlightenment property of accuracy of the direction of search is strengthened.

In basic PSO algorithm, with the increase of iterations, the diversity of population can constantly reduce, and easily produces " precocity " phenomenon.Introduce mutation operation and disturbance operation herein and reduced the possibility that population is absorbed in local extremum.

Concrete, in embodiment mono-, when transfer ratio r=50%, by improved particle cluster algorithm, calculating optimum gain is K _dC=0.53.Now, 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 do not adopt HVDC Modulation (K _dC=0) situation contrast time as shown in Figure 9.

Finally should be noted that: above embodiment is only in order to illustrate that technical scheme of the present invention is not intended to limit, although the present invention is had been described in detail with reference to above-described embodiment, those of ordinary skill in the field are to be understood that: still can modify or be equal to replacement the specific embodiment of the present invention, and do not depart from any modification of spirit and scope of the invention or be equal to replacement, it all should be encompassed in the middle of claim scope of the present invention.

Claims (5)

1. a method that suppresses alternating current interconnection random power fluctuation, is characterized in that, described method changes DC line power to shift the random power fluctuation on alternating current interconnection by setting up DC power modulation controller, and described method comprises:

Step S1, determines the design object of described DC power modulation controller according to the transfer ratio r setting;

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

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

The standard deviation function that wherein σ () is signal; σ (P _t) be alternating current interconnection power P _tstandard deviation; σ (P _dC) be DC line power P _dCstandard deviation;

Step S2, described DC power modulation controller comprises measurement links, every straight link and gain link, the power P that modulation signal is alternating current interconnection _t, according to measurement links with every straight link time constant T _mesand τ _wand the ride gain K of gain link _dCwith modulation signal P _tdetermine the model of described DC power modulation controller;

The ride gain K of described gain link _dCgain K for described DC power modulation controller definite in described step S1 _dC;

In described step S1, according to the transfer ratio r setting, determine that the design object of described DC power modulation 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 _dCfor the gain of described DC power modulation controller, J is the performance index of described DC power modulation 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 measuring-signal; T is simulation time; μ (x) is the mean value function of signal x

2. the method for claim 1, is characterized in that, in described step S2, the transfer function of described measurement links is

described is eliminate or reduce in measuring-signal close to the component of direct current every straight link object, and transfer function is $\frac{{\mathrm{\&tau;}}_w}{1+{\mathrm{\&tau;}}_{w}s}.$

3. the method for claim 1, is characterized in that, described method also comprises:

Step S3, adopts improved particle cluster algorithm to optimize described DC power modulation controller parameter.

4. method as claimed in claim 3, is characterized in that, the method that adopts improved particle cluster algorithm to optimize the parameter of described DC power modulation controller in described step S3 is:

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

If search volume is D dimension, population is N, and in population, the position of i particle is u _i(u _i1, u _i2..., u _iD), the speed of i particle is v _i(v _i1, v _i2..., v _iD), the position of each particle is a potential solution; In each iteration, each particle upgrades oneself by following the tracks of 4 extreme values, and described 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), the condition of the speed of calculating particle and position convergence is that iteration reaches given maximum step number or disturbance number of times reaches set-point;

The speed of i particle d dimension in the k+1 time iteration and position

renewal equation be:

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

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

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 ₄for accelerated factor; ω is the inertia weight factor.

5. method as claimed in claim 4, it is characterized in that, in described step S3, introduce the possibility that mutation operation and disturbance operation minimizing population are absorbed in local extremum, the enlightenment that the accuracy that adopts the dynamic strategy that changes inertia weight to strengthen the direction of search obtains.

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