Hello, thank you so much again for your answer to the problem of negative resistances. I still have doubts though. Considering precisely the T diagram for the 3-winding transformer (that of your attached) the possible negative resistance that I find myself is RM? How do I know the value of the other resistances? I will eventually only have 2 rows of mpc.branch used for the 3-winding transformer or am I wrong?
Thank you so much in advance I hope I don't bother you too much Il giorno ven 18 giu 2021 alle ore 15:01 Russ Patterson <r...@relayman.org> ha scritto: > Hi Simone, > > > > The negative branch is due to the conversion of pair-wise transformer test > data to “T” model. See if the attached helps. It is not a “real” negative > physical value – it is necessary for the mathematical model. > > > > Best regards, > > russ > > > > > > > > *From:* bounce-125719454-88411...@list.cornell.edu [mailto: > bounce-125719454-88411...@list.cornell.edu] *On Behalf Of *Simone Fratton > *Sent:* Friday, June 18, 2021 5:17 AM > *To:* MATPOWER discussion forum > *Subject:* Re: Negative resistance > > > > Thank you very much for your answer, but I am not sure that I have yet > understood why; especially if at the end it's about having a transformer > with negative resistance. > > > > Il giorno ven 18 giu 2021 alle ore 11:08 Dirk Van Hertem < > dirk.vanher...@ieee.org> ha scritto: > > Hello, > > Negative resistances normally correspond to equivalent branches... > > Dirk > > On 18/06/2021 11:04, Simone Fratton wrote: > > Hello everyone, > > I wanted to ask you if anyone knows exactly why in some cases the > resistance of mpc.branch is negative? Or at least if someone has any good > ideas. > > For example, case3012wp has as many as 10 negative resistances (all refer > to a transformer). > > Thank you all very much. > >
