5节点电力系统潮流计算matlab程序

%1.形成节点导纳矩阵,
yb55=6.250-18.750j;yb51=-5.000+15.000j;yb52=-1.250+3.750j;yb53=0.000-0.000j;yb54=0.000-0.000j;
yb15=-5.000+15.000j;yb11=10.834-32.500j;yb12=-1.667+5.000j;yb13=-1.667+5.000j;yb14=-2.500+7.500j;
yb25=-1.250+3.750j;yb21=-1.667+5.000j;yb22=12.917-38.750j;yb23=-10.000+30.000j;yb24=0.000-0.000j;
yb35=0.000-0.000j;yb31=-1.667+5.000j;yb32=-10.000+30.000j;yb33=12.917-38.750j;yb34=-1.250+3.750j;
yb45=0.000-0.000j;yb41=-2.500+7.500j;yb42=0.000-0.000j;yb43=-1.250+3.750j;yb44=3.750-11.250j;
YB=[yb11 yb12 yb13 yb14 yb15; yb21 yb22 yb23 yb24 yb25 ;yb31 yb32 yb33 yb34 yb35; yb41 yb42 yb43 yb44 yb45 ;yb51 yb52 yb53 yb54 yb55];
disp('节点导纳矩阵YB=');
disp(YB);
%计算各节点功率的不平衡量设U=E+jF ；Y=G+Bj；
E(1)=1.00;E(2)=1.00;E(3)=1.00;E(4)=1.00;
F(1)=0;F(2)=0;F(3)=0;F(4)=0;
G=real(YB);B=imag(YB);
%设S=P+Bj；

S(1)=0.20+0.20i;S(2)=-0.45-0.15i;S(3)=-0.40-0.05i;S(4)=-0.60-0.10i;

P=real(S);Q=imag(S);
k=0;precision=1;
N1=4;
while precision > 0.00001
E(5)=1.06;F(5)=0;

for m=1:N1
for n=1:N1+1
%计算Pi,Qi,设Pi=Pt;Qi=Qt
Pt(n)=(E(m)*(G(m,n)*E(n)-B(m,n)*F(n))+F(m)*(G(m,n)*F(n)+B(m,n)*E(n)));
Qt(n)=(F(m)*(G(m,n)*E(n)-B(m,n)*F(n))-E(m)*(G(m,n)*F(n)+B(m,n)*E(n)));
end
%设P,Q的改变量为dP,dQ
dP(m)=P(m)-sum(Pt);
dQ(m)=Q(m)-sum(Qt);
end
for m=1:N1
for n=1:N1+1
%计算Hij Nij Jij Lij
H(m,n)=-B(m,n)*E(m)+G(m,n)*F(m);
N(m,n)=G(m,n)*E(m)+B(m,n)*F(m);
J(m,n)=-B(m,n)*F(m)-G(m,n)*E(m);
L(m,n)=G(m,n)*F(m)-B(m,n)*E(m);
end
end
for m=1:N1
for n=1:N1+1
Bi(n)=G(m,n)*F(n)+B(m,n)*E(n);
Ai(n)=G(m,n)*E(n)-B(m,n)*F(n);
end
%sum(Ai)，sum(Bi)用于实现公式中的sigerma从j到n的求和;
H(m,m)=sum(Bi)-(B(m,m)*E(m)+G(m,m)*F(m))+2*G(m,m)*F(m);
N(m,m)=sum(Ai)-(G(m,m)*E(m)-B(m,m)*F(m))+2*G(m,m)*E(m);
J(m,m)=-2*B(m,m)*F(m)+sum(Ai)-(G(m,m)*E(m)-B(m,m)*F(m));
L(m,m)=-2*B(m,m)*E(m)-(sum(Bi)-(B(m,m)*E(m)+G(m,m)*F(m)));

end
%设雅可比矩阵为JJ，以下语句用来实现雅可比矩阵中对角线上元素H N J L 的排列
for m=1:N1

JJ(2*m-1,2*m-1)=H(m,m);
JJ(2*m-1,2*m)=N(m,m);

JJ(2*m,2*m-1)=J(m,m);
JJ(2*m,2*m)=L(m,m);
end
%以下语句用于实现雅可比矩阵非对角线上元素的排列
for m=1:N1
for n=1:N1
if m==n
else

H(m,n)=-B(m,n)*E(m)+G(m,n)*F(m);
N(m,n)=G(m,n)*E(m)+B(m,n)*F(m);
J(m,n)=-B(m,n)*F(m)-G(m,n)*E(m);
L(m,n)=G(m,n)*F(m)-B(m,n)*E(m);


JJ(2*m-1,2*n-1)=H(m,n);
JJ(2*m-1,2*n)=N(m,n);

JJ(2*m,2*n-1)=J(m,n);
JJ(2*m,2*n)=L(m,n);


end
end
end

%

设由P,Q的改变量组成的8×1矩阵为PQ，由E,F的改变量组成的8×1矩阵为dU
for m=1:N1
PQ(2*m-1)=dP(m); PQ(2*m)=dQ(m);
end
dU=inv(JJ)*PQ';
precision=max(abs(dU));

for n=1:N1

F(n)=F(n)+dU(2*n-1);
E(n)=E(n)+dU(2*n);
end

for n=1:N1+1
U(n)=E(n)+(F(n))*j;
end
k=k+1;
k-1, dU=dU',PQ,U
end