MATLAB Answers

what is mistake in my matlab code

1 view (last 30 days)
Quynh tran
Quynh tran on 2 Apr 2016
Commented: Rena Berman on 20 Jan 2017
Ybusn(linedata)=
Columns 1 through 5
14.7752 - 6.4985i 0.0000 + 0.0000i 0.0000 + 0.0000i -14.7752 + 6.4985i 0.0000 + 0.0000i
0.0000 + 0.0000i 14.7752 - 6.4985i 0.0000 + 0.0000i 0.0000 + 0.0000i -14.7752 + 6.4985i
0.0000 + 0.0000i 0.0000 + 0.0000i 14.7752 - 6.4985i 0.0000 + 0.0000i 0.0000 + 0.0000i
-14.7752 + 6.4985i 0.0000 + 0.0000i 0.0000 + 0.0000i 26.1902 - 9.6810i -11.4150 + 3.1825i
0.0000 + 0.0000i -14.7752 + 6.4985i 0.0000 + 0.0000i -11.4150 + 3.1825i 37.6052 -12.8635i
0.0000 + 0.0000i 0.0000 + 0.0000i -14.7752 + 6.4985i 0.0000 + 0.0000i -11.4150 + 3.1825i
Column 6
0.0000 + 0.0000i
0.0000 + 0.0000i
-14.7752 + 6.4985i
0.0000 + 0.0000i
-11.4150 + 3.1825i
26.1902 - 9.6810i
phi =
0.9840 - 0.0134i 0.0000 + 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i
0.0000 + 0.0000i 0.9808 - 0.0125i 0.0000 + 0.0000i 0.0000 + 0.0000i
0.0000 + 0.0000i 0.0000 + 0.0000i 0.9795 - 0.0122i 0.0000 + 0.0000i
0.0000 + 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i -0.0000 - 0.0000i
C =
1.0000 + 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i
0.0000 + 0.0000i 1.0000 + 0.0000i 0.0000 + 0.0000i 0.0000 + 0.0000i
0.0000 + 0.0000i 0.0000 + 0.0000i 1.0000 + 0.0000i 0.0000 + 0.0000i
-0.4669 + 0.0010i -0.4669 + 0.0010i -0.4669 + 0.0010i -0.4669 + 0.0010i
-0.2139 - 0.0103i -0.2139 - 0.0103i -0.2139 - 0.0103i -0.2139 - 0.0103i
-0.3193 + 0.0093i -0.3193 + 0.0093i -0.3193 + 0.0093i -0.3193 + 0.0093i
Zbus=1/Ybus;
PG1=0.0923;
PG2=0.1368; %sau nay chinh lai de chon nut dieu chinh cong suat phat
PG3=0.0792;
Pgg=[PG1,PG2,PG3,1];
%tinh dong dien nhanh
e=ybusn(linedata);
linebranch=zeros(nbr,3);
Ig=phi*Pgg';
Ibus=C*Ig;
V=Zbus*Ibus;
for k=1:nbr
if nl(k)>0 && nr(k)>0
Ibranch(k)=abs(-(V(nl(k))-V(nr(k)))*e(nl(k),nr(k)));
end
end
Ibranch;
linebranch(:,1)=linedata(:,1);
linebranch(:,2)=linedata(:,2);
linebranch(:,3)=Ibranch';
disp([ ' nl nr |I|' ]);
disp([linebranch]);
%Kiem tra dong nhanh
nbr=length(linedata(:,1));
Imax=linedata(:,7);
flag=0;
niter=0;
n=0
while (flag==0&&niter<90)
for n=1:nbr
if linebranch(n)>Imax(n)
niter=niter+1;
PG2=PG2-0.001;
Pgg=[PG1,PG2,PG3,1];
Ig=phi*Pgg';
Ibus=C*Ig;
V=Zbus*Ibus;
for k=1:nbr
if nl(k)>0 && nr(k)>0
Ibranch(k)=abs(-(V(nl(k))-V(nr(k)))*e(nl(k),nr(k)));
end
end
else
flag=1;
end
end
end
Ibranch
I changed my new code. It work ok but the loop is not stop when Ibracnh<Imax.Please post your answer in a new answer let me know you online and answer you soon, don't post in comment.
  4 Comments
Rena Berman
Rena Berman on 20 Jan 2017
(Answers Dev) Restored Question.

Sign in to comment.

Accepted Answer

Kuifeng
Kuifeng on 2 Apr 2016
Edited: Walter Roberson on 2 Apr 2016
i think maybe your loop never finishes.... endlesss loop in the 'Ibranch'
k = 1;
while k<=nbr % k run in the number of branch
while Ibranch(k)>Imax(k) %to check Ibranh in each of branch
PG2=PG2-0.001;
Pgg=[0.0923,PG2,0.0792,1];
V=Zbus*(C*(phi*Pgg'));
k=k+1;
% caculate again the Ibranch in branch;
end
end
  1 Comment
Quynh tran
Quynh tran on 2 Apr 2016
Many thanks for your answer. I tried as you talk, with your code, it even not work and freezing the program.

Sign in to comment.

More Answers (2)

Walter Roberson
Walter Roberson on 2 Apr 2016
Your code has
while Ibranch(k)>Imax(k) %to check Ibranh in each of branch
but inside the "while" you do not appear to change Ibranch or Imax or k. If the condition becomes true once, then it appears that you are going to get an infinite loop.
However, you do have the line of code
caculate again the Ibranch in branch;
which, due to MATLAB's command / function equivalence, would be the same as calling
calculate('again', 'the', 'Ibranch', 'in', 'branch')
and we have no information about any function named "calculate" or how that function is going to modify Ibranch or Imax . It could happen. It just looks unlikely.
  5 Comments
Quynh tran
Quynh tran on 2 Apr 2016
as you talk, I change my variable name. But have a new problem, that is the loop is not stop, it run enough niterloop even when the the Ibranch<Imax

Sign in to comment.


Tags

No tags entered yet.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by