Basically, I am trying to solve just a normal power flow with an optimization process being called externally. The problem is that compute several input values can take hours with my current code. That's why I am trying to run a Optimal Power Flow with costs equal to zero if possible. If not, I would like to know how to reduce my computation time when running PF.
Just in case, I already edited options so I can remove printing on Command Window. Nevertheless, the optimization is not working when I call it outside (too slow and it is not behaving the way I want to) and, for bad and for good, OPF allows me to optimize my function calling it intrinsecally, in spite of having to assume costs and I don't need them right now, but eventually yes though. So, I would appreciate any help regarding to it. Best regards and thanks in advance. 2017-02-23 20:51 GMT+01:00 Ray Zimmerman <[email protected]>: > What problem are you trying to solve? If you don’t have an objective > function then the OPF is probably not the right tool. Unless there is a > unique feasible solution, you need some way of ranking the typically > infinite number of feasible solutions so it can give you an “optimal” one. > > Ray > > > On Feb 23, 2017, at 2:20 PM, BRENDA ROJAS DELGADO <[email protected]> > wrote: > > Hi, Ray: > > I have the same issue. My grid is being studied with OPF and even tough I > knew from the beginning that gencost matrix cannot be supressed at all, I > have tried to assume that gencost=0 in order to not take into count any > cost so far. > > But Matpower doesn't accept gencost=0 and I don't know why. I would like > to have a solution to my problem because when I use Matpower with a > Optimization Tool belonging whether to Matlab or Opti Toolbox, it takes too > long the computation time and that's an advantage I would like to keep on > taking of when running an OPF. > > Thanks is advance for the reply. Best regards > > Brenda Rojas > > > > El jueves, 23 de febrero de 2017, Ray Zimmerman <[email protected]> > escribió: > >> The OPF (and the problem solved by MOST) are optimization problems, which >> means they are attempting to minimize some cost subject to constraints. So, >> no, you can’t eliminate the cost function. If you aren’t trying to minimize >> a cost, I’m not sure that MOST or OPF are the right tools. >> >> And, by the way, the error you are seeing appears to be related to >> dispatchable loads (which also make no sense without a corresponding >> benefit or “cost”). >> >> Ray >> >> >> On Feb 21, 2017, at 7:03 AM, Alberto Claudio Alvisi < >> [email protected]> wrote: >> >> Hi, >> >> I've just written saturday about my problem: >> >> >> "Dear all, >> >> I'm working on my thesis using MATPOWER, but I' ve this problem with >> MOST tool: >> >> *Error using .* * >> *Matrix dimensions must agree.* >> >> *Error in most (line 2116)* >> * mpc.gen(ivl, QG) = mpc.gen(ivl, PG) .* Qlim ./ Pmin(ivl);* >> >> *In particular: * >> >> *Qlim =* >> >> * []* >> >> mpc.gen(ivl, PG) >> >> ans = >> >> Empty matrix: 0-by-1." >> >> >> *After I've read more documentation about MATPOWER and MOST tool, I >> understand that the OPF solution required to find the min f(x) with a >> constraint of cost.* >> *I've a case without gencost and I prefer to not create a gencost matrix >> to solve it because the cost of PG don't matter in my case. * >> *It's possible to impose that MATPOWER doesn't study the cost of PG >> during the solution process? In other words, is there a MATPOWER option to >> leave the cost constraint?* >> >> >> *Thanks a lot for your contribution* >> >> *Regards* >> >> >> ALBERTO CLAUDIO ALVISI >> *Student at University Of Bologna* >> >> >> >
