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>
