a) You'll have to try it to see if it works for your system. I just know that Newton method power flow is more likely to have convergence issues as the system moves to higher R/X ratios.
b) I simply mean that MATPOWER does not model all 3 phases explicitly; it assumes the 3 phases are balanced and simply uses a single phase to represent the positive sequence components to approximate the 3-phase operation. If you don't know what I'm talking about, check out a good textbook (or on-line tutorial) on symmetrical components for 3-phase networks. -- Ray Zimmerman Senior Research Associate 419A Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Apr 18, 2013, at 8:54 AM, Aftognosia Aftognosia <[email protected]> wrote: > Dr Zimmerman > Regarding the modelling of a radial distribution system (eg 11kV system) , > you informed me that MATPOWER should work fine, > except for high R/X ratios. > > a) Could you please specify this numerically? ie R/X > 2 is an example of a > high ratio that could cause problems in MATPOWER ? > > b) Furthermore, when you are referring to a 'balanced system' , what exactly > do you mean? > In distribution systems, 'balanced' system sometimes is the system that has > all its lateral feeders having the same load. > Or do you mean you mean that MATPOWER cannot work with loads such as > inverters, drives , etc which are non-linear? > > Thank you > > > > From: Ray Zimmerman <[email protected]> > To: MATPOWER discussion forum <[email protected]> > Sent: Tuesday, April 16, 2013 1:20 PM > Subject: Re: MATPOWER > > It should work fine depending on the parameters. Very high R/X ratios in the > lines can possibly cause numerical difficulties. And, of course, MATPOWER > would only model a balanced system. It does not model an unbalanced 3-phase > network. > > -- > Ray Zimmerman > Senior Research Associate > 419A Warren Hall, Cornell University, Ithaca, NY 14853 > phone: (607) 255-9645 > > > > > On Apr 15, 2013, at 1:36 PM, Aftognosia Aftognosia <[email protected]> > wrote: > >> Hello, >> >> Is it possible to use MATPOWER in order to implement ACOPF in a radial >> distribution system ? >> >> Are there any limitations for distribution system? >> >> > > >
