Thank you very much. All the previous mails those I sent you in which I wanted to differentiate wind turbine from other types of generators because this I wanted to have specified power factor. Because want to have for example 5 DGs: 3 diesel generators and 2 WTs for example.
Regards Carlos On Fri, Mar 18, 2011 at 19:55, Ray Zimmerman <[email protected]> wrote: > I often simulate a wind turbine as a negative load (a fixed P + Q > injection), or as a generator with zero cost. The Q capability would depend > on the type of turbine. > > To remove a generator, you can either switch it off by setting it's > GEN_STATUS to 0 (which causes it to be removed internally) or remove the > corresponding rows in the data matrices after they are loaded. > > gen(k, :) = []; > gencost(k, :) = []; > ... > > -- > Ray Zimmerman > Senior Research Associate > 211 Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > On Mar 18, 2011, at 2:13 PM, Carlos Gonzalez Almeida wrote: > > Thank you. But if you want to have Wind turbine how will you simulate it in > MATPOWER? > > also, I want to have 5 generators instead of 6 generators in the case of > ('t_auction_case'). Is there a command to remove one of the generators > without changing the file, i.e. removing the correspond rows, gencost, > offers and .....? > Best Regards > > carlos > > On Fri, Mar 18, 2011 at 18:51, Ray Zimmerman <[email protected]> wrote: > >> As I've said before, I think the problem is that you have unrealistic >> expectations about the ability to operate a power system with strictly >> specified power factors on all generators. It is not reasonable to expect >> that an OPF with a constant power factor constraint on the generators will >> be feasible over any significant range of power factors. >> >> -- >> Ray Zimmerman >> Senior Research Associate >> 211 Warren Hall, Cornell University, Ithaca, NY 14853 >> phone: (607) 255-9645 >> >> >> >> On Mar 17, 2011, at 2:43 PM, Carlos Gonzalez Almeida wrote: >> >> Thank you. In your idea what changes should be carried out to do >> runmarket, for the case pf set to 0.97 for example? >> >> Best Regards >> Carlos >> >> On Thu, Mar 17, 2011 at 19:35, Ray Zimmerman <[email protected]> wrote: >> >>> Carlos, >>> >>> It appears that with such strict constraints on power factor it is no >>> longer able to keep the voltages within limits. Notice when you run the case >>> you sent with the PF set to 0.9, there are both upper and lower voltages >>> limits binding. >>> >>> -- >>> Ray Zimmerman >>> Senior Research Associate >>> 211 Warren Hall, Cornell University, Ithaca, NY 14853 >>> phone: (607) 255-9645 >>> >>> >>> >>> On Mar 17, 2011, at 12:35 PM, Carlos Gonzalez Almeida wrote: >>> >>> Dear Prof. Zimmerman >>> >>> In the case provided in manual(t_auction_case), when I do runmarket (with >>> the attached offers and bids) with power factors between 0.5 to 0.9 there is >>> no problem but with the PF greater then 0.9 it doesn't work. If it is >>> possible could you please see it what is the reason? Please see the attached >>> file >>> >>> Best Wishes >>> >>> C. Gonzalez Almeida >>> >>> >>> On Thu, Mar 17, 2011 at 10:47, Carlos Gonzalez Almeida < >>> [email protected]> wrote: >>> >>>> Thank you very much for your guidance. I solved the problem. >>>> >>>> Best Regards >>>> >>>> Carlos >>>> >>>> >>>> On Wed, Mar 16, 2011 at 23:28, Ray Zimmerman <[email protected]> wrote: >>>> >>>>> No, it doesn't make sense to have bids without dispatchable loads. What >>>>> would the bids correspond to if there are no dispatchable resources on the >>>>> demand side of the market? >>>>> >>>>> Again, to me, specifying the power factor for everything doesn't make >>>>> sense. But if you insist, then you'll have to do what I said before, >>>>> create >>>>> an A matrix with constant power factor constraints for the actual >>>>> generators >>>>> only, not including the dispatchable loads (which already have their own >>>>> constant power factor constraints created automatically by MATPOWER). >>>>> >>>>> -- >>>>> Ray Zimmerman >>>>> Senior Research Associate >>>>> 211 Warren Hall, Cornell University, Ithaca, NY 14853 >>>>> phone: <%28607%29%20255-9645> <%28607%29%20255-9645>(607) 255-9645 >>>>> >>>>> >>>>> >>>>> On Mar 16, 2011, at 12:25 PM, Carlos Gonzalez Almeida wrote: >>>>> >>>>> Yes. without converting loads to dispatchable loads is it possible to >>>>> insert bids? if yes how? >>>>> >>>>> my problem is this, with only offers I can do runmarket but with both >>>>> offers and bids I cannot do runmarket with specified PF. How can I do >>>>> this? >>>>> >>>>> On Wed, Mar 16, 2011 at 17:21, Ray Zimmerman <[email protected]> wrote: >>>>> >>>>>> It doesn't matter what the power factor is, you cannot give two >>>>>> conflicting power factor constraints for a dispatchable load. There is >>>>>> one >>>>>> that is created automatically by MATPOWER from the Q/P ratio of the load >>>>>> ( >>>>>> QMIN/PMIN) and the other you are adding explicitly. If the one you >>>>>> specify explicitly is different from the one automatically created by >>>>>> MATPOWER, then you have made the problem infeasible and it will not >>>>>> work. If >>>>>> they are the same then you have added redundant constraints that could >>>>>> potentially cause numerical issues. >>>>>> >>>>>> So, for loads, set the power factor directly by setting the P and Q in >>>>>> the bus matrix (or gen matrix if you are not using load2disp) and do >>>>>> not add explicit power factor constraints via the *A* matrix. >>>>>> >>>>>> -- >>>>>> 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 16, 2011, at 12:00 PM, Carlos Gonzalez Almeida wrote: >>>>>> >>>>>> Thank you very much for your help. >>>>>> >>>>>> for any power factor(0.85,0.95,0.9, ....) I have this problem. The >>>>>> value of PF is not important for me. The important thing is that I >>>>>> cannot do >>>>>> runmarket with the specified power factor as I want. >>>>>> >>>>>> Best Regards >>>>>> >>>>>> Carlos >>>>>> >>>>>> On Wed, Mar 16, 2011 at 16:51, Ray Zimmerman <[email protected]>wrote: >>>>>> >>>>>>> The problem here is that you've made the problem infeasible by adding >>>>>>> conflicting constraints. Remember, dispatchable loads are implemented as >>>>>>> generators (with PMAX = 0 and PMIN < 0). Each dispatchable load already >>>>>>> has >>>>>>> a constant power factor constraint, included automatically by MATPOWER, >>>>>>> that >>>>>>> keeps the Q/P ratio equal to the original ratio. This ratio is not zero >>>>>>> for >>>>>>> the loads in case9, but you have added another constraint to these >>>>>>> "generators" trying to force the power factor to equal 1 (Q/P ratio = >>>>>>> 0) and >>>>>>> these constraints conflict. You need to modify *A*, *l* and *u*, to >>>>>>> only include rows for the original generators, not the dispatchable >>>>>>> loads. >>>>>>> Check out the isload function to help you find which are the real >>>>>>> gens. >>>>>>> >>>>>>> I still question why forcing the power factor to equal 1 for all >>>>>>> generators except the reference gen is so important to you. Are any real >>>>>>> power systems ever operated under such constraints? >>>>>>> >>>>>>> -- >>>>>>> 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>(607) >>>>>>> 255-9645 >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Mar 16, 2011, at 7:04 AM, Carlos Gonzalez Almeida wrote: >>>>>>> >>>>>>> Dear Prof. Zimmerman >>>>>>> >>>>>>> I want to do runmarket with following offers and bids also with PF=1 >>>>>>> for generators and the following error is occurred. >>>>>>> Could you please help me? >>>>>>> >>>>>>> *define_constants; >>>>>>> mpc0= loadcase('case9'); >>>>>>> mpc = load2disp(mpc0); >>>>>>> offers.P.qty = [200; 150; 180]; >>>>>>> offers.P.prc = [30; 40; 50]; >>>>>>> bids.P.qty = [70; 70; 70]; >>>>>>> bids.P.prc = [100; 90; 80]; >>>>>>> mkt.OPF = 'AC'; >>>>>>> nb = size(mpc.bus, 1); >>>>>>> ng = size(mpc.gen, 1); >>>>>>> pf = 1; >>>>>>> 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:end, :); >>>>>>> mpc.l = zeros(ng-1, 1); >>>>>>> mpc.u = mpc.l; >>>>>>> [r, co, cb] = runmarket(mpc, offers, bids, mkt);* >>>>>>> >>>>>>> Results >>>>>>> >>>>>>> *Warning: Matrix is singular to working precision. >>>>>>> > In mips at 422 >>>>>>> In mipsopf_solver at 145 >>>>>>> In opf_execute at 106 >>>>>>> In opf at 225 >>>>>>> In uopf at 154 >>>>>>> In smartmkt at 90 >>>>>>> In runmarket at 141 >>>>>>> Warning: Matrix is singular to working precision. >>>>>>> > In mips at 422 >>>>>>> In mipsopf_solver at 145 >>>>>>> In opf_execute at 106 >>>>>>> In opf at 225 >>>>>>> In uopf at 154 >>>>>>> In smartmkt at 90 >>>>>>> In runmarket at 141 >>>>>>> >>>>>>> SMARTMARKET: non-convergent UOPF??? Error using ==> mtimes >>>>>>> Inner matrix dimensions must agree. >>>>>>> >>>>>>> Error in ==> smartmkt at 170 >>>>>>> price = mkt.lim.P.max_offer * ones(ng, 1); >>>>>>> >>>>>>> Error in ==> runmarket at 141 >>>>>>> [co, cb, r, dispatch, success] = smartmkt(mpc, offers, bids, mkt, >>>>>>> mpopt);* >>>>>>> >>>>>>> Best Wishes >>>>>>> >>>>>>> Carlos >>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> Best Wishes >>>>>> >>>>>> C. Gonzalez Almeida >>>>>> >>>>>> >>>>>> >>>>> >>>>> >>>>> Best Wishes >>>>> >>>>> C. Gonzalez Almeida >>>>> >>>>> >>>>> >>>> >>>> >>>> Best Wishes >>>> >>>> C. Gonzalez Almeida >>>> >>> >>> <pf_constraint_eg1.m> >>> >>> >>> >> >> >> Best Wishes >> >> C. Gonzalez Almeida >> >> >> > > > Best Wishes > > C. Gonzalez Almeida > > > Best Wishes C. Gonzalez Almeida
