Its always best to send query emails directly to the MATPOWER forum as you'll 
get suggestions from more than person.

The current OPF in MATPOWER assumes constant tap ratios and phase shifters so 
that the Ybus, Yf, and Yt matrices are constant in the optimization. Hence, 
these matrices are calculated before the OPF iterations begin and passed as an 
input to opf_consfcn, the OPF constraints evaluation routine. (see 
mipsopf_solver.m). In your case, Ybus, Yf, and Yt need to be updated during 
every constraint function evaluation with the tap and phase shifts from the 
current iterate x.

Assuming you have set up the sizes/indexing information correctly and have 
modified the appropriate structs, in opf_consfcn, you need to (a) extract the 
taps and phase shifts from x, (b) plug them into the appropriate columns of the 
branch matrix (note that branch(:,SHIFT) is in degrees), and c) call makeYbus 
to update Ybus, Yf, and Yt.

Shri

From: Mirish Thakur 
<[email protected]<mailto:[email protected]>>
Date: Wed, 7 Jan 2015 00:47:19 +0100
To: Shri <[email protected]<mailto:[email protected]>>
Subject: Need help in MATPOWER problem.

Dear Abhyankar Shrirang,

I'm master student at Kalsruhe Institute of Technology, Germany. Right now I'm 
working on project power system optimization with additional variables tap 
ratio and phase shift in 9 bus system and I'm using mipsopf_solver. For this I 
have referred Mr. Laurens Bliek's document.(http://arxiv.org/abs/1311.5115)  I 
have problem with updating the values of "tap" and "shift" in "make Y bus"  
function file. In earlier augmentation these values were not realized by 
mipsopf_solver  and it has problem with convergence ( showed error : 
Numerically failed). Now I have to update these values in make Y bus. For that 
I have tentative idea but not concrete script to write.

if ~isempty(vargin{1});
 shift = branch(:, SHIFT);
  tap = branch(:, TAP);
 end
if is tap subject to OPF
[tap shift] = get shift tap values from OPF solver (op)
end

This is what I want to write in code.

Rest of the part i have augmented wherever i needed it.This is substantial 
problem I'm facing now. I really need your favor as I have very short time left 
in my hand to get output. I'm waiting for your reply. Herewith I have attached 
screen shot of my function file.
Thanking you in anticipation.

Best regards
Mirish Thakur

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