Thanks you very much for the solution. Amalia.
Στις Τετ, 14 Νοε 2018, 17:57 ο χρήστης Ray Zimmerman <[email protected]> έγραψε: > The *AC power flow* (runpf) appears to solve just fine. > > >> mpc = loadcase('existing_system'); > >> mpopt = mpoption('verbose', 1, 'out.all', 0); > >> r = runpf(mpc, mpopt); > > MATPOWER Version 7.0b1, 31-Oct-2018 -- AC Power Flow (Newton) > > Newton's method power flow converged in 3 iterations. > > > The *OPF* (runopf), on the other hand, does not converge, probably > because it is infeasible. > > >> mpopt = mpoption('verbose', 1, 'out.bus', 0, 'out.branch', 0, > 'out.sys_sum', 0); > >> r = runopf(mpc, mpopt); > > MATPOWER Version 7.0b1, 31-Oct-2018 -- AC Optimal Power Flow > AC OPF formulation: polar voltages, power balance eqns > MATPOWER Interior Point Solver -- MIPS, Version 1.3, 30-Oct-2018 > (using built-in linear solver) > Numerically Failed > > Did not converge in 5 iterations. > > >>>>> Did NOT converge (0.22 seconds) <<<<< > > > The problem of determining the cause of the infeasibility is a good > candidate for the *OPF soft limits* feature (newly expanded in v7.0b1). > > >> mpc = toggle_softlims(mpc, 'on'); > >> r = runopf(mpc, mpopt); > > MATPOWER Version 7.0b1, 31-Oct-2018 -- AC Optimal Power Flow > AC OPF formulation: polar voltages, power balance eqns > MATPOWER Interior Point Solver -- MIPS, Version 1.3, 30-Oct-2018 > (using built-in linear solver) > Converged! > > Converged in 0.59 seconds > Objective Function Value = 16232.27 $/hr > > . > . > . > > > ================================================================================ > | Soft Generator Reactive Power Upper Bounds > | > > ================================================================================ > Gen Bus Generation Limit Overload mu > # # Q (MVAr) Q (MVAr) (MVAr) ($/MVAr) > ----- ----- -------- ------- ------- --------- > 1 1 0.85 -3.50 4.35 1000.000 > 2 1 0.85 -3.50 4.35 1000.000 > 3 1 0.85 -3.50 4.35 1000.000 > -------- > Total: 13.04 > . > . > . > > > ================================================================================ > | Soft Branch Flow Limits > | > > ================================================================================ > Brnch From To Flow Limit Overload mu > # Bus Bus (MVA) (MVA) (MVA) ($/MVA) > ----- ----- ----- -------- -------- -------- --------- > 1 1 2 2.95 1.50 1.45 1000.000 > 3 1 4 3.32 2.25 1.07 1000.000 > 4 1 5 2.18 1.50 0.68 1000.000 > -------- > Total: 3.19 > > > So, it looks like both the generator QMAX and the branch RATE_A values are > too restrictive, making the problem infeasible. I’m not sure what the > actual reactive power range is intended to be, but you currently have QMIN > = 0, QMAX = –3.5 (less than QMIN!) and QG = 4.5. You want values where QMIN > < QG < QMAX. > > Ray > > > On Nov 14, 2018, at 5:53 AM, Αμαλία Μαυρογιάννη <[email protected]> > wrote: > > I am working on an island system. I make a case where I depict the whole > system. The lines are in 15KV and there are 3 generators in 5MW each. I run > an AC power flow (runopf)and the message is Did not converge in 5 > iterations. I have done the : > > * define_constants; mpcbase = loadcase('casefile'); mpcbase.bus(:, PD) = > 0; mpcbase.bus(:, QD) = 0; mpcbase.gen(:, PG) = 0; mpctarget = > loadcase('casefile'); results = runcpf(mpcbase, mpctarget); * > > * results.cpf.max_lam* > > > and max_lam=10.5284. > > The runcpf doesn't run at all. > > The case is down. > > Thanks > Amalia Mavrogianni > <existing_system.m> > > >
