Thank you very much dear Prof. Zimmerman My problem is that I don't understand the sparse() function used to construct the *A* matrix especially don't understand how the *A* matrix defined in the example implements a constant power factor constraint. The latter is very important for me. I will be greatly appreciated you if you explain me further.
Best Regards Carlos On Tue, Mar 15, 2011 at 15:41, Ray Zimmerman <[email protected]> wrote: > In order to help you further, you're going to have to be more specific > about what it is that you are having trouble with. Is it that you don't > understand the sparse() function used to construct the *A* matrix? Or that > you don't understand how the *A* matrix is used? Or you don't understand > how the *A* matrix defined in the example implements a constant power > factor constraint? > > Btw, if anyone else on the list can see something I'm missing in my > attempts to help Carlos get up to speed ... jump in, don't be shy. > > -- > Ray Zimmerman > Senior Research Associate > 211 Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > On Mar 15, 2011, at 9:31 AM, Carlos Gonzalez Almeida wrote: > > Dear Prof. Zimmerman > > Once again I appreciate you for the file that you sent me. Where can I find > more information about the way of definition of A matrix. I have read the > manual but I didn't understand well, for example in the case you sent me > yesterday. If it is possible either please introduce me a book or explain a > little bit more about A matrix in general. > > Best Wishes > > C. Gonzalez Almeida > > > On Mon, Mar 14, 2011 at 19:05, Carlos Gonzalez Almeida < > [email protected]> wrote: > >> Thank you very very much. >> >> On Mon, Mar 14, 2011 at 18:59, Ray Zimmerman <[email protected]> wrote: >> >>> Did you understand the previous example? If so, it's a trivial >>> modification (attached). If not, please go back and familiarize yourself >>> with the extended OPF formulation in the manual, the paper, the slides for >>> the paper, etc. This is about the most trivial example can think of for >>> adding a user-defined constraint to the OPF. >>> >>> >>> >>> -- >>> Ray Zimmerman >>> Senior Research Associate >>> 211 Warren Hall, Cornell University, Ithaca, NY 14853 >>> phone: <%28607%29%20255-9645> >>> <%28607%29%20255-9645><%28607%29%20255-9645>(607) >>> 255-9645 >>> >>> >>> >>> On Mar 14, 2011, at 12:16 PM, Carlos Gonzalez Almeida wrote: >>> >>> With more details I want to do runmarket and I want to have PF=0.85 for >>> example in case9 for generators 2, 3. How can I do it? >>> >>> Best Wishes >>> >>> C. Gonzalez Almeida >>> >>> >>> On Mon, Mar 14, 2011 at 17:10, Carlos Gonzalez Almeida < >>> [email protected]> wrote: >>> >>>> Thank you. >>>> >>>> I also have the Roberto's problem as well as in the case of runmarket to >>>> set an specified power factor for generators except slack bus. >>>> >>>> If it is possible please give an example. Because it can be useful for >>>> other people who will use in the future MATPOWER. >>>> >>>> Best Wishes >>>> >>>> C. Gonzalez Almeida >>>> >>>> >>>> On Mon, Mar 14, 2011 at 16:59, Ray Zimmerman <[email protected]> wrote: >>>> >>>>> 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: <%28607%29%20255-9645> >>>>> <%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645>(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: <%28607%29%20255-9645> >>>>>> <%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645>(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: <%28607%29%20255-9645> >>>>>>> <%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645>(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: <%28607%29%20255-9645> >>>>>>>>> <%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645>(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: <%28607%29%20255-9645> >>>>>>>>>> <%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645><%28607%29%20255-9645>(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 >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> >>>> >>> >>> >>> >> >> >> Best Wishes >> >> C. Gonzalez Almeida >> > > > Best Wishes C. Gonzalez Almeida
