Dear Prof. Zimmerman, I am really sorry about that. I really apologize for the way of writing. So sorry about that.
Would you mind letting me know how I can modify the code in order to have variable power factor? I was not able to apply your comments. I'll be very grateful if you can help me please. Once again, I do apologize. Best regards, Carlos On Fri, Sep 25, 2015 at 6:34 PM, Ray Zimmerman <[email protected]> wrote: > Please do not keep asking us to provide you with the modifications to the > code. You haven’t told us which part of that code you are having trouble > understanding. > > There is a big difference between … > > 1. Can you please help me understand so I can do it? and … > 2. Can you do it for me? > > I’m happy to try to do #1. I’m not interested in #2 (except possibly if > hired as a consultant). > > Ray > > > > > On Sep 23, 2015, at 8:26 AM, Carlos Marta Gonzalez Almeida < > [email protected]> wrote: > > Dear Dr. Zimmerman, > > What modifications I have to apply to the following code? Thanks > > > *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;* >>> >>> > > Best regards > > C > > > On Tue, Sep 22, 2015 at 2:25 PM, Ray Zimmerman <[email protected]> wrote: > >> That wouldn’t be correct anyway. The power factor is not the same as the >> Q/P ratio. And you will need two separate sets of constraints, one for the >> upper bound on the power factor and the other for the lower bound on the >> power factor. >> >> Ray >> >> >> >> On Sep 22, 2015, at 2:56 AM, Carlos Marta Gonzalez Almeida < >> [email protected]> wrote: >> >> 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;* >>>> >>>> >>>> >>> >>> >> >> > >
