Both cases have a all generator cost functions equal to zero, so all feasible power flow solutions are optimal. That is, there isn’t even a unique *local* optima, let alone a global optima. Under such circumstances, numerical optimization routines such as those used by MATPOWER, should not be expected to produce anything unique or consistent. Adding a small quadratic real power cost for each generator does result in consistent solutions for the two cases (to numerical accuracy of the algorithms).
-- Ray Zimmerman Senior Research Associate B30 Warren Hall, Cornell University, Ithaca, NY 14853 USA phone: (607) 255-9645 On Sep 1, 2014, at 10:42 AM, vids <[email protected]> wrote: > Hi Matpower Community, > > I was testing the application of reactive capability curve limits. I > defined a generator operating region by using the points described in > section 6.4.3 in the manual. > I first performed the OPF without including the parameters, and then > compared it with the results when the PQ curve limitation was > included. I was expecting the same results because the operating point > is very well within the operating region defined by the limits. But > the results were two slightly different operating points. Is this > really how Matpower behaves? I am attaching the two case files, in > case. Thank you very much! > > Vids > <capabilitytests_1.m><capabilitytests_2.m>
