On Nov 12, 2007, at 2:36 PM, Martin Elfstadius wrote:
I want to run multiple DC OPF:s with changing limits on certain
transmission lines.
I can't figure out which columns I need to change.
I am using the t_auction_case.m to simulate a bidauction taking place.
I've tried changing the sixth column in the branch matrix to the
case file.
[
4 12 0.0 0.26 0.0 limit 65.0 65.0 0.0 0.0
1;
23 24 0.13 0.27 0.0 limit 16.0 16.0 0.0 0.0
1];
I obtain somewhat the expected behaviour when I change the limit but
something is strange.
This is the correct parameter for limiting line flow. What in
particular was strange about the result?
I've only been able to simulate congestion by putting the last
column to zero.
Making the transmission line 'out of service'. limit = 0 won't do it.
I've also tried changing the other rates in coulumns 7 and 8 without
results.
How am I able to simulate congestion without putting them out of
service?
I want to be able to simulate 98% congestion aswell, not only 100%.
What do you mean by simulating congestion? You want the line
constraint to be binding at the solution?
I'm not sure I understand exactly what you mean by 98% congestion.
By the way, setting the limit to 0 and setting the status to 0
represent very different scenarios. Setting the limit to zero means
that the line is physically in place, but you are attempting to
dispatch generation in a way that results in zero flow on the line.
This may not be possible. Make sure that you check the "success"
return variable from rundcopf to make sure that it is finding a
solution. If "success" returns a false value, it probably means the
problem is infeasible.
--
Ray Zimmerman
Senior Research Associate
428-B Phillips Hall, Cornell University, Ithaca, NY 14853
phone: (607) 255-9645
