The voltage is given 4.16kV. I convert the impedances to p.u. by myself with 1MVA base. Actually I have checked this model in 'runpf()' and the result is almost the same as shown in IEEE 123 node profile. So I guess the problem might be the generation cost setting. I'm trying to fix that problem.
Thank you very much! *Fanjun Meng Electrical Engineering Missouri University of Science & Technology [email protected] <[email protected]>* On Wed, Jun 29, 2011 at 2:39 AM, Simon Schneider <[email protected]>wrote: > ** > Are the nodal voltage limits set wide enough(e.g. 0.9 an 1.1)? > Another possible source could be a bad choice of baseMVA and base voltage. > Do you convert the impedances by yourself or are they already given in > p.u? > > Regards, > Simon > Am 6/28/2011 10:05 PM, schrieb Fanjun Meng: > > Thanks a lot! > > *Fanjun Meng* > > > > On Tue, Jun 28, 2011 at 12:36 PM, Santiago Torres <[email protected] > > wrote: > >> Maybe the generation costs you are using for the opf are causing >> problems. Try to check that!. >> >> Regards, >> >> Santiago >> >> 2011/6/28 Fanjun Meng <[email protected]> >> >>> Thank you very much for your suggestion! >>> Actually I did check the simple power flow result with constraints, the >>> voltages, line flows, generations are all satisfied. That's why I'm confused >>> with this problem. Is it possible that the line impedences and system >>> topology may cause matrix sigularity during OPF calculation iteration and >>> fail to converge? >>> >>> Thanks a lot! >>> >>> *Fanjun Meng >>> * >>> >>> >>> >>> >>> On Tue, Jun 28, 2011 at 10:13 AM, Santiago Torres < >>> [email protected]> wrote: >>> >>>> The simple power flow has not constraints, so maybe with the settings >>>> you are using the power flow converges and has solution, however when >>>> you use the opf, some constraints can cause it does not converge. Check if >>>> the IEEE 123 node reported solution when using the simple power flow >>>> is complying the constraints (ie voltages, power generation, power flows). >>>> >>>> I hope this can help. >>>> >>>> Santiago Torres >>>> >>>> 2011/6/28 Fanjun Meng <[email protected]> >>>> >>>>> Hello, >>>>> >>>>> I've been working on IEEE 123 nodes system and created a model for >>>>> MatPower power flow. This model is basically a radial distribution system >>>>> with a single generation at substation and works fine when I can use >>>>> runpf(), and it returns similar result as shown IEEE 123 node system >>>>> report. >>>>> However, when I use the same model for runopf(), it shows >>>>> >>>>> >>>>> Numerically Failed >>>>> Did not converge in 4 iterations. >>>>> Did not converge (0.10 seconds) >>>>> >>>>> The total generation is very different from total demand, and bus >>>>> voltages are at strange values (e.g. 1.836p.u. at reference bus). Also, >>>>> generation cost Lambda are extremely high (e.g. 17528752586.76 $/MWh @ bus >>>>> 6). I have tried to add multiple DGs at different locations and change the >>>>> system to a ring type system, but it didn't work out. Does anyone have any >>>>> suggestions or experiences to this problem? Your help is highly >>>>> appreciated! >>>>> >>>>> Have a good day!* >>>>> >>>>> Fanjun Meng >>>>> * >>>>> >>>>> >>>> >>>> >>>> -- >>>> Dr.-Ing. Santiago Torres >>>> IEEE Senior Member >>>> >>>> Post-Doctoral Fellow >>>> School of Electrical and Computer Engineering >>>> University of Campinas, Campinas, SP, Brazil >>>> >>>> http://www.dsee.fee.unicamp.br/ >>>> >>>> Albert Einstein, 400 >>>> 13083-852, Campinas, SP, Brazil >>>> >>> >>> >> >> >> -- >> Dr.-Ing. Santiago Torres >> IEEE Senior Member >> >> Post-Doctoral Fellow >> School of Electrical and Computer Engineering >> University of Campinas, Campinas, SP, Brazil >> >> http://www.dsee.fee.unicamp.br/ >> >> Albert Einstein, 400 >> 13083-852, Campinas, SP, Brazil >> > > >
