Lambda interpolates between the [P_base, Q_base] and [P_target, Q_target] vectors of your choice, so therefore the relationship between the lambda stepsize and the actual power increase on the buses depends on that.
-- Jose L. Marin Gridquant España SL Grupo AIA On Wed, Aug 12, 2015 at 12:16 PM, nilesh patel <nk2...@rediffmail.com> wrote: > > Sir, > If i want to increase load in continuation power flow by step of 1 MW, > What should be the step size of Lamda. My system base case load is 5000 MW. > As CPF accuracy depends on step-size. > > Thanks. > > > > From: Jose Luis Marin <mari...@gridquant.com> > Sent: Mon, 10 Aug 2015 18:53:11 > To: MATPOWER discussion forum <matpowe...@list.cornell.edu> > Subject: Re: PV curve using CPF > > Shruti is right, the value you obtain for lambda is valid for all the > network, since voltage collapse is a global phenomenon (in other words, > you';ll see a nose point at the same value of lambda regardless of which > bus you choose to plot). Remember that lambda represents a fraction along > the vector of injections linearly iterpolating [P_base, Q_base] to > [P_target, Q_target]. The value of Lambda at the nose point is NOT the > maximum loading point for that bus; rather, it is the maximum loading value > along the path to the particular load/gen profile chosen as a target. > > Of course, one may wonder about this other problem: for a given profile > [P_base, Q_base], what is the target direction [P_target, Q_target] for > which one would obtain the shortest value of critical lambda? If this is > what you';re thinking about, then it is in general a hard problem. I > suggest these references by Ian Dobson, on the concept of "shortest > distance" to voltage collapse: > > - http://www.ece.wisc.edu/~dobson/PAPERS/publications.html#loading > <http://www.ece.wisc.edu/~dobson/PAPERS/publications.htmlloading> > > > -- > Jose L. Marin > Gridquant España SL > Grupo AIA > > > > On Mon, Aug 10, 2015 at 6:23 AM, nilesh patel <nk2...@rediffmail.com> > wrote: > >> >> Sir, >> When we run continuation power flow for particular system, we get p-v >> curve for selected bus. using this p-v curve, we can find Voltage stability >> Margin (in MW) on that bus by difference of operating point to nose point >> lamda. >> I agree lambda at nose point provides maximum loading value but >> that is for that bus only for which p-v curve is plotted. >> >> My question is How to find Voltage Stability Margin for whole Network >> using P-V curve ? I mean how to find maximum lamda for whole network using >> p-v curve? >> >> Thanks. >> >> From: "Abhyankar, Shrirang G." <abhy...@anl.gov> >> Sent: Fri, 07 Aug 2015 22:31:31 >> To: MATPOWER discussion forum <matpowe...@list.cornell.edu> >> Subject: Re: PV curve using CPF >> I donⴠquite understand your question, can you please elaborate. >> >> The maximum value of loading scaling parameter ᬡmbda⠧ives a measure of >> how much power can be transferred for a given transfer direction. So, >> lambda is also a measure of the nose point for the whole network. >> >> Shri >> >> From: nilesh patel <nk2...@rediffmail.com> >> Reply-To: MATPOWER discussion forum <matpowe...@list.cornell.edu> >> Date: Friday, August 7, 2015 at 8:46 AM >> To: matpower-l <matpowe...@list.cornell.edu>, MATPOWER-L < >> MATPOWER-L@cornell.edu> >> Subject: PV curve using CPF >> >> Dear Sir, >> P-V curve solution using continuation power flow gives nose point >> (maximum loading point) for individual bus. >> >> My question is - How to get nose point for whole network (all buses) >> using PV curve ? I want to find network voltage stability margin rather >> than individual bus margin using CPF. >> >> Thanks. >> >> >> Nilesh Patel >> >> Get your own *FREE* website, *FREE* domain & *FREE* mobile app with >> Company email. >> <//www.rediffmail.com/cgi-bin/red.cgi?red=https%3A%2F%2Fsigads%2Erediff%2Ecom%2FRealMedia%2Fads%2Fclick%5Fnx%2Eads%2Fwww%2Erediffmail%2Ecom%2Fsignatureline%2Ehtm%40Middle%3F&isImage=0&BlockImage=0&rediffng=0&rogue=86405da3ed8eb9005549e1536a8c08bb6cef0c3e> >> *Know More >* >> >> > Get your own *FREE* website, *FREE* domain & *FREE* mobile app with > Company email. > *Know More >* > <http://track.rediff.com/click?url=___http://businessemail.rediff.com?sc_cid=sign-1-10-13___&cmp=host&lnk=sign-1-10-13&nsrv1=host> > <https://sigads.rediff.com/RealMedia/ads/click_nx.ads/www.rediffmail.com/signatureline.htm@Middle?> > > > > <https://sigads.rediff.com/RealMedia/ads/click_nx.ads/www.rediffmail.com/signatureline.htm@Middle?> > Get your own *FREE* website, *FREE* domain & *FREE* mobile app with > Company email. > *Know More >* > <http://track.rediff.com/click?url=___http://businessemail.rediff.com?sc_cid=sign-1-10-13___&cmp=host&lnk=sign-1-10-13&nsrv1=host> >
