MATPOWER does have the option to use a Gauss-Seidel method (PF_ALG = 4). I don't have experience using it for networks with high R/X ratios. You'll have to try it on your system to see how well it works.
-- Ray Zimmerman Senior Research Associate 419A Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Apr 19, 2013, at 1:27 PM, Aftognosia Aftognosia <[email protected]> wrote: > Yes , the Newton Raphson LF has convergence issues for high R/X ratios. > However , does MATPOWER only utilize NR method ? > If I could change the method by which is solved the Load Flow, would it be > able to still operate for high R/X ratios? > > Thank you > > > From: Ray Zimmerman <[email protected]> > To: MATPOWER discussion forum <[email protected]> > Sent: Friday, April 19, 2013 2:27 PM > Subject: Re: Distribution system > > 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? >>> >>> >> >> >> > > >
