1. You can constrain a generator to have a zero power factor by setting PMIN = PMAX = 1. The generator reactive power is one of the optimization variables in x, so it's value is determined by whatever solver you happen to be using, MIPS by default. So I suppose if you need to know which m-file computes its value, it would be mips.m. If you want to set the reactive power of generator 2 to zero, simply set both the QMIN and QMAX column in the corresponding row of the gen matrix to zero (by the way, that is a power factor of 1, not 0).
Without more details I have no idea. Are you passing in any reactive power offers? -- Ray Zimmerman Senior Research Associate 211 Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Mar 14, 2011, at 6:17 AM, Carlos Gonzalez Almeida wrote: > Dear Prof. Zimmerman > > 1.I studied the your response to Roberto Carvalini but I don't know how can I > define the PF for other generators to zero or other values when I do > runmarket and it doesn't work the code when I do runmarket. By which formula > you have computed the generator reactive power (in which m.file, please > address the m.file because I couldn't find it). For example, if I want to set > reactive power of generator 2 to zero, what should I do? > > 2. Why I cannot do runmarket for case30Q and case9Q? what is the reason? > > > Best Wishes > > C. Gonzalez Almeida > > > On Fri, Mar 11, 2011 at 16:29, Ray Zimmerman <[email protected]> wrote: > See my response to Roberto Carvalini, posted only seconds ago. Am I fast or > what? ;-) > > -- > Ray Zimmerman > Senior Research Associate > 211 Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > On Mar 11, 2011, at 10:16 AM, Carlos Gonzalez Almeida wrote: > >> Thank you very much. >> >> Could you please give me an example about defining power factor for >> generators? >> >> I cannot set it. >> >> On Fri, Mar 11, 2011 at 16:09, Ray Zimmerman <[email protected]> wrote: >> 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 >>> >>> >>> >>> >> >> >> >> >> Best Wishes >> >> C. Gonzalez Almeida > > >
