My problem is that I cannot implement matrix A in order to have -0.95*P<Q<P*0.95. What changes I have to apply to A matrix?
Regards, Carlos On Mon, Sep 21, 2015 at 3:43 PM, Ray Zimmerman <[email protected]> wrote: > You really do need to understand what that code is doing before you can > make modifications to make it do something else. So, to repeat my main > question … is there a particular part of that code that you are having > trouble understanding? > > It is setting up a constraint *l* <= *A* * *x* <= *u*, where *x* = [*Va*; > *Vm*; *Pg*; *Qg*], so you need to define the *A*, *l* and *u* to restrict > the *Qg*/*Pg* ratio in a way the enforces the power factor range you > desire. You have an example of how to enforce the Qg/Pg ratio to a specific > value that corresponds to a given power factor. Once you understand that, > it should be trivial to get rid of the appropriate bound (*l* or *u*) to > change it to an upper or lower bound on the power factor. Then you add a > similar and opposite bound for another power factor value for the other end > of your range. > > But, as I said … the first step is to fully understand the example you > have. > > Ray > > > > On Sep 21, 2015, at 2:37 AM, Carlos Marta Gonzalez Almeida < > [email protected]> wrote: > > DEar Dr. Zimmerman, > > I don't know how I should change the equality constraint to inequality > constraint. I'll be very grateful if you can help me. > > Best regards, > > Carlos > > On Fri, Sep 18, 2015 at 4:12 PM, Ray Zimmerman <[email protected]> wrote: > >> *Please address MATPOWER support questions (including followup’s to this >> e-mail) to the MATPOWER mailing list >> <http://www.pserc.cornell.edu/matpower/#mailinglist>.* >> >> You simply have to change the equality constraint to an inequality >> constraint. Is there a particular part of that code snippet that you are >> having trouble understanding? >> >> Ray >> >> >> On Sep 1, 2015, at 11:58 AM, Carlos Marta Gonzalez Almeida < >> [email protected]> wrote: >> >> Dear Dr. Zimmerman, >> >> According to your previous posts on the following equation which makes >> the power factor constant. Now I want to have power factor varying between >> -0.95 and 0.95. What changes to the following equation to be made? >> >> Thank you very much. >> >> Carlos >> >> >> >> *ng = size(mpc.gen, 1);* >> *pf = 0.95;* >> *QPratio = sqrt(1/pf^2 -1);* >> >> *mpc.A = sparse([1:ng 1:ng]', [2*nb+(1:ng) 2*nb+ng+(1:ng)]', >> [QPratio*ones(ng,1); -ones(ng,1)], ng, 2*nb+2*ng);* >> >> *mpc.A = mpc.A(2:10, :);* >> *mpc.l = zeros(ng-15, 1);* >> *mpc.u = mpc.l;* >> >> >> > >
