【正文】 )。endJ=[H,N。L(i,i)=L(i,i)U(i)*U(j)*(G(i,j)*sin(a(i)a(j))B(i,j)*cos(a(i)a(j)))endendN(i,i)=N(i,i)2*(U(i))^2*G(i,i)。N(i,i)=N(i,i)U(i)*U(j)*(G(i,j)*cos(a(i)a(j))+B(i,j)*sin(a(i)a(j)))。M(i,j)=N(i,j)。N(i,j)=U(i)*U(j)*(G(i,j)*cos(a(i)a(j))+B(i,j)*sin(a(i)a(j)))。endx2=[oP,oQ]39。endoP(i)=oP(i)+P(i)。endend% 求有功、無功功率不平衡量for i=1:4for j=1:5oP(i)=oP(i)U(i)*U(j)*(G(i,j)*cos(a(i)a(j))+B(i,j)*sin(a(i)a(j)))。oP(i)=0。M(i,j)=0。while max(x2)1e6for i=1:4for j=1:4H(i,j)=0。x2=ones(8,1)。a=zeros(1,5)。% 賦初值，U為節(jié)點(diǎn)電壓的幅值，a為節(jié)點(diǎn)電壓的相位角U=ones(1,5)。P=real(S)。S(4)=。S(2)=。B=imag(Y)。endendend% 求節(jié)點(diǎn)導(dǎo)納矩陣中自導(dǎo)納for i=1:5Y(i,i)=sum(y(i,:))。endendY=0。y(3,4)=1/(+)。y(2,3)=1/(+)。y(1,4)=1/(+)。y(4,5)=0。% 如圖所示1，2，3，4為PQ節(jié)點(diǎn),5為平衡節(jié)點(diǎn)y=0。2 基本步驟和設(shè)計流程圖形成了雅克比矩陣并建立了修正方程式，運(yùn)用牛頓拉夫遜法計算潮流的核心問題已經(jīng)解決，已有可能列出基本計算步驟并編制流程圖。電力系統(tǒng)潮流計算，一般來說，各個母線所供負(fù)荷的功率是已知的，各個節(jié)點(diǎn)的電壓是未知的（平衡節(jié)點(diǎn)外）可以根據(jù)網(wǎng)絡(luò)結(jié)構(gòu)形成節(jié)點(diǎn)導(dǎo)納矩陣，然后由節(jié)點(diǎn)導(dǎo)納矩陣列寫功率方程，由于功率方程里功率是已知的，電壓的幅值和相角是未知的，這樣潮流計算的問題就轉(zhuǎn)化為求解非線性方程組的問題了。二 牛頓拉夫遜法潮流計算 1 基本原理牛頓法是取近似解x(k)之后，在這個基礎(chǔ)上，找到比x(k)更接近的方程的根，一步步地迭代，找到盡可能接近方程根的近似根。例題如下：用牛頓拉夫遜法計算下圖所示系統(tǒng)的潮流分布，其中系統(tǒng)中5為平衡節(jié)點(diǎn)，節(jié)點(diǎn)5電壓保持U=，其他四個節(jié)點(diǎn)分別為PQ節(jié)點(diǎn)，給定的注入功率如圖所示。同時基于MATLAB的計算機(jī)算法以雙精度類型進(jìn)行數(shù)據(jù)的存儲和運(yùn)算, 數(shù)據(jù)精確度高，能進(jìn)行潮流計算中的各種矩陣運(yùn)算，使得傳統(tǒng)潮流計算方法更加優(yōu)化。t have to be corrected.(2),Calculation of asymmetric system harmonic power flowIn the asymmetric threephase system, the t conditions of each phase are not identical, and influence each other, so the calculation of threephase system must be conducted at the same of the tide of asymmetric network can be conducted by dividing the network into every harmonic network, puting the fundamental network first, after get the voltage of base wave at each node, harmonic wave of all injected current is calculated according to it, then calculate the network equations of every harmonic according to harmonic current injected, work out the every harmonic voltage of each The presence of harmonics in power system is a kind of “contamination” in the power system reduce the quality of the waveform of system voltage, not only affect the power system itself seriously, but also harm the user and the surrounding munication the study of power system harmonic is of great significance in improving the power quality, restraining and eliminating harmonics.第二篇：電力系統(tǒng)潮流計算南 京 理 工 大 學(xué)《電力系統(tǒng)穩(wěn)態(tài)分析》課程報告姓名XX學(xué) 號： 5*** 自動化學(xué)院 電氣工程基于牛頓拉夫遜法的潮流計算例題編程報學(xué)院(系): 專業(yè): 題目: 任課教師 碩士導(dǎo)師 告楊偉 XX2015年6月10號基于牛頓拉夫遜法的潮流計算例題編程報告摘要：電力系統(tǒng)潮流計算的目的在于：確定電力系統(tǒng)的運(yùn)行方式、檢查系統(tǒng)中各元件是否過壓或者過載、為電力系統(tǒng)繼電保護(hù)的整定提供依據(jù)、為電力系統(tǒng)的穩(wěn)定計算提供初值、為電力系統(tǒng)規(guī)劃和經(jīng)濟(jì)運(yùn)行提供分析的基礎(chǔ)。s each kind of nonlinear electric example: Converter equipment, regulator device, electrified railway, electricarc furnace, fluorescence the lamp, the domestic electric appliances and kinds of electronic energy conservation control device and so on are the important source of electrical power system if these equipment supplies the ideal sine wave voltage, the electric current it takes is also nonlinear, namely the harmonic current the harmonic current the equipment produces will also pour into the electrical power system, which will cause existence of harmonic ponent in the system voltage of each overtone that has nothing to do with the electrical power system parameter in these equipment decided its characteristic and working condition, which maybe regarded as source of the overtone with constant , the overtone generated by the nonlinear element in the power supply system itself is another are many kinds of nonlinear example: transformer excitation branch , Ac/dc converter thyristor control element, thyristor controlled capacitor, reactor, , The harmonic ponent produced by user electric equipment will also impact on the as fluorescent lamps, household appliances with a small capacity has a large quantity and spread in the power sector has difficulty in managing such harmonic content current of these devices is too large, it will cause serious impact to power system,and the manufacturing number of the current harmonic content of this kind of equipment should be limited in a certain , Harmonic voltage from generator is another is sued to produce the rated voltage but at the same time also engender harmonic voltage which is determined by the structure and the working conditions of the harmonic voltage has nothing to do with external impedance that can be treated as the harmonic constant voltage source, but its value is very , The calculation of power system harmonic power flow is pleted by solve the network equations In = YnUn(n = 3, 5, 7...n: number of : Harmonic current’s n times column injected into power grid by load that is considered as the harmonic : n times harmonic admittance matrix of power : n times harmonic voltage of each bus nodes in the grid column).We can get the power grid harmonic voltage of each node(bus)then the harmonic current of each current there are harmonic sources exist in the power system, the system of contact voltages and branch currents will have higher order to determine the distribution of harmonic voltage and harmonic current in power supply system , we need do calculation of power flow for equivalent circuit consisted by harmonic the same time, when capacitive ponent exist in rectifying device in the power supply system, also according to the nature and size of each branch of harmonic impedance to verify presence of resonance do harmonic power flow calculation, we must determine the harmonic impedance of power grid element Power grid harmonic impedance of all kinds of ponents: impedance of synchronous generatorQualified potential is pure sine generator, do not contain high order harmonic, the generator voltageis only the base higher harmonic network, due to the harmonic voltage generator is very small, we can regard harmonic voltage generator as zero at this , its equivalent circuit is harmonic reactance that connected to the machine side and XGn = nXG1(1)Type of XG1 is fundamental wave gen