I tried with the «dual-simplex» and it seems to work very well. I didn’t get 
convergence issues anymore.
Thank you!

Camille

From: [email protected] 
[mailto:[email protected]] On Behalf Of Ray Zimmerman
Sent: 19. januar 2016 15:39
To: MATPOWER discussion forum <[email protected]>
Subject: Re: DC-OPF convergence issues with dispatchable loads

I suspect you are right that it is a numerical issue with the interior point 
solvers. However, linprog() has solvers other than the interior-point method 
[1], including primal simplex and, in recent versions, dual-simplex. I suggest 
you try one of the following …

mpopt = mpoption(‘opf.dc.solver', ‘OT’, 'linprog.Algorithm', ‘simplex’);
mpopt = mpoption(‘opf.dc.solver', ‘OT’, 'linprog.Algorithm', 'dual-simplex’);
mpopt = mpoption(‘opf.dc.solver', ‘OT’, 'linprog.Algorithm', ‘primal-simplex’);

The dual simplex method seems to have improved quite a bit in the most recent 
versions.

    Ray


[1] 
http://www.mathworks.com/help/optim/ug/linprog.html?refresh=true#input_argument_options


On Jan 19, 2016, at 4:16 AM, Camille Hamon 
<[email protected]<mailto:[email protected]>> wrote:

Dear all,

I recently ran into a problem running a simple DC-OPF with dispatchable loads. 
I defined all nonzero loads to be dispatchable using:
mpc = load2disp(mpc);

Then, I ran a DC-OPF. It did not converge (I tried using the OT and MIPS 
solvers; both did not converge).
I tried to run the same DC-OPF without setting the loads as dispatchable and it 
converged.
I then tried to re-run the DC-OPF with dispatchable loads but this time without 
line constraints (setting RATE_A to large values) and it converged. I checked 
the power flows in the solution and all power flows were under the original 
line constraints.

It seems the problem is related to the interior-point solvers OT and MIPS. 
Since these are the only solvers available on my machine, I could not try with 
other solvers.
I would be grateful for any help or hint on this issue.

Best regards
Camille


Reply via email to