Carlos, If you want the loads to have a power factor of 0.95, you need to set QD such that PD/sqrt(PD^2 + QD^2) = 0.95, i.e. QD has to equal 0.108 * PD. About the voltage constraint of 1.5 p.u., I don't see that anywhere, so I'm not sure what you are referring to. The different lambdas at the two buses are due to losses. The power factor of the generators is determined by the solution algorithm within the bounds set for them. That is, each generator has a feasible "box" defined by PMIN, PMAX, QMIN and QMAX. You don't normally "set" the power factor of a generator as input to the OPF. I suppose, if for some reason you have a strict power factor constraint on a generator you could use some additional linear constraints to the OPF to enforce it, but that would be unusual I think.
-- Ray Zimmerman Senior Research Associate 211 Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Mar 10, 2011, at 8:10 AM, Carlos Gonzalez Almeida wrote: > Another question is this: when I have not fixed loads only I have > dispatchable loads how can I define power factor for generators and loads > separately? > > Best Wishes > > Carlos > > On Thu, Mar 10, 2011 at 13:53, Carlos Gonzalez Almeida > <[email protected]> wrote: > Dear Prof. Zimmerman > > Thanks a lot for your useful guidance. > > For example, in the attached file for a simple case study with 2 loads and > generators I want to have a power factor 0.95. I have problem with adjusting > power factor in MATPOWER. How can I do it in the attached file? Also I don't > know why I have voltage constraint 1.5 pu. I think because of these > constraints I have a little bit difference in the value of lambda > I have done runmarket with the following offers and bids. > Could you please tell me why? > > +++++++++++++++++++++ > mpc0 = loadcase('case4gs1'); > mpc = load2disp(mpc0); > mkt.OPF = 'AC'; > offers.P.qty = [100;70]; > offers.P.prc = [50;100]; > bids.P.qty = [50 ;70 ]; > bids.P.prc = [150 ;130 ]; > [r, co, cb] = runmarket(mpc, offers, bids, mkt); > co.P.qty > co.P.prc > cb.P.qty > cb.P.prc > ++++++++++++++++++++++++ > > Best Wishes > > C. Gonzalez Almeida > > > > On Wed, Mar 9, 2011 at 19:47, Ray Zimmerman <[email protected]> wrote: > Carlos, > > I'm not sure what you mean by "test the example ... regarding zero power > factor". If you are going to change some of the existing dispatchable loads > to have a zero power factor, then the existing market structure for the > example, which includes only $/MW bids for active power, will not be > applicable. So you need to decide how you want to handle these reactive-only > loads. I suppose you'll need to specify reactive power bids for them. > > On your second question, the offers and bids are used to construct a gencost > matrix with negative costs for the negative generators that represent > dispatchable loads. The objective function is then to minimize this "cost" of > generation, which is computed in opf_costfcn.m. You are correct that this is > equivalent to maximizing social welfare. > > -- > Ray Zimmerman > Senior Research Associate > 211 Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > On Mar 8, 2011, at 5:04 PM, Carlos Gonzalez Almeida wrote: > >> Dear Dr. Zimmerman >> >> -Could you please test the example provided in the manual (t_auction_case) >> regarding zero power factor. What changes should be carried out? >> >> -Moreover, as you know, the objective function obtained in the runmarket is >> Social welfare. Could you please address me the file that you calculated >> objective function because I couldn't find it. I want to know in which file >> (the m file) you have calculated that? >> >> Best Regards >> >> Carlos >> >> >> >> On Tue, Mar 8, 2011 at 22:34, Ray Zimmerman <[email protected]> wrote: >> I'm not really sure without seeing the details of your example. I'm not sure >> I've ever tested the runmarket code with pure reactive power loads. It would >> require reactive power bids for those loads, but I'll need the details to be >> able to help you further. >> >> -- >> Ray Zimmerman >> Senior Research Associate >> 211 Warren Hall, Cornell University, Ithaca, NY 14853 >> phone: (607) 255-9645 >> >> >> >> On Mar 7, 2011, at 10:42 AM, Carlos Gonzalez Almeida wrote: >> >>> Hi >>> >>> I am new in MATPOWER abd I want to have zero power factor for example in >>> example case of manual in runmarket, but several error are occured. please >>> tell me why >>> >>> >>> Best Wishes >>> >>> C. Gonzalez Almeida >> >> >> >> >> Best Wishes >> >> C. Gonzalez Almeida > > > >
