电力系统稳态分析课程设计---两机五节点网络潮流计算-牛拉法

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第三节 MATLAB程序

clc clear

disp('节点总数为：'); N=5

disp('平衡节点为：'); 1

disp('PQ节点为：'); JD=[2,3,4,5]

Y=[6.25-18.75i -5+15i -1.25+3.75i 0 0; -5+15i 10.834-32.5i -1.667+5i -1.667+5i -2.5+7.5i; -1.25+3.75i -1.667+5i 12.917-38.75i -10+30i 0; 0 -1.667+5i -10+30i 12.917-38.75i -1.25+3.75i;

0 -2.5+7.5i 0 -1.25+3.75i 3.75-11.25i]

G=real(Y);B=imag(Y); B1=B(2:5, 2:5);

B2=B1; b1=inv(B1); b2=inv(B2); dt(2)=0; dt(3)=0;

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dt(4)=0; dt(5)=0; u(2)=1.0; u(3)=1.0; u(4)=1.0; u(5)=1.0; p(2)=0.20; p(3)=-0.45; p(4)=-0.40; p(5)=-0.60; q(2)=0.20; q(3)=-0.15; q(4)=-0.05; q(5)=-0.10; k=0;wucha=1; N1=4;

while wucha(1)>0.00001; dt(1)=0;u(1)=1.06; for m=2:5 for n=1:5

pt(n)=u(m)*u(n)*(G(m,n)*cos(dt(m)-dt(n))+B(m,n)*sin(d

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t(m)-dt(n))); end

disp('各节点有功率不平衡量为：') dp(m)=p(m)-sum(pt) end for m=2:5 u1=diag(u);

u2=inv(u1(2:5,2:5)); u3=flipud(rot90(u(2:5))); u4=u3(1:4,:);

dp1=flipud(rot90(dp(2:5))); dp2=dp1(1:4,:); dtt=(-b1*dp2/u4)*u2; dtt=dtt(:,1:1); dtt=flipud(rot90(dtt))

disp('各节点电压的相位角dt为：') dt(m)=dt(m)+dtt(m-1) end for m=2:5 for n=1:5

qt(n)=u(m)*u(n)*(G(m,n)*sin(dt(m)-dt(n))-B(m,n)*cos(dt(

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