The convergence behavior of the Newton-Raphson power flow is certainly related to bus voltages (and algorithm starting points), so I’m not surprised that it converges with some tap settings and not with others. Determining which cases will solve and which will not is a very problem dependent task, so I’m not sure I can give you any general help that will be useful for your particular case.
(It also seems you changed multiple things between the case that did not converge and the one that did, so I don’t know which one(s) were important.) -- Ray Zimmerman Senior Research Associate B30 Warren Hall, Cornell University, Ithaca, NY 14853 phone: (607) 255-9645 On Dec 16, 2013, at 5:29 AM, fron <[email protected]> wrote: > Hello, > > We are starting to use matpower in a electrical power distribution system, so > we configure a small case with 118 branches and 80 buses. > > To determine the optimal configuration we programmed a search algorithm with > PF (not OPF). In that algorithm we set the transformer's TAP to one of the > following values: 0.95;0.975;1;1.025, 1,05. (The relation of our transformer > is 15kV/0.4kV). > > We have a problem when more than 70% of our transformers have TAPS=0.95, PF > algorithms give us a "no convergence". > > But if we modify the BASE_KV field and we set the relation of transformer in > 15kV/0.42kV we have not got problems (with the taps in 1) > > Can you help us with this problem? > > Thanks. > > > Fernando ron >
