The constraints corresponding to columns 11-21 in the gen matrix are optional
(i.e. the columns can contain all zeros), but those columns are not to be
treated as optional columns. It turns out that some functions, such as runopf()
will not cause an error and, yes, the results returned are correct. However,
other MATPOWER functions will fail if there are missing columns (e.g. savecase).
I suppose I could just modify loadcase() to add any missing columns, so that we
can explicitly treat them as optional columns … just added that to the to-do
list.
Ray
> On Jan 12, 2015, at 1:00 PM, Simone Cochi <[email protected]> wrote:
>
> Does the missing value in the gen struct affect the results? I thought they
> were optional constraints
>
>> Il giorno 12/gen/2015, alle ore 17:24, Ray Zimmerman <[email protected]
>> <mailto:[email protected]>> ha scritto:
>>
>> (First of all, this is not a valid MATPOWER case file … the gen matrix needs
>> to have 21 columns).
>>
>> I’m pretty sure these are simply numerical issues. Your network has a huge
>> range for branch reactances (from 1e-4 up to 7.2415), and I’m sure the zero
>> cost generation doesn’t help. It turns out that some solvers do converge
>> (IPOPT, MINOPF, TRALM) using the default starting point, and others (MIPS
>> and KNITRO) converge if you use the power flow solution to initialize the
>> OPF.
>>
>> Ray
>>
>> E.g.
>>
>> >> load mpc
>> >> mpopt = mpoption('verbose', 2, 'opf.ac.solver', 'MIPS',
>> >> 'out.suppress_detail', 1, 'opf.init_from_mpc', 1);
>> >> r = runopf(mpc, mpopt);
>> >>
>> MATPOWER Version 5.0, 17-Dec-2014 -- AC Optimal Power Flow
>> MATLAB Interior Point Solver -- MIPS, Version 1.1, 17-Dec-2014
>> it objective step size feascond gradcond compcond
>> costcond
>> ---- ------------ --------- ------------ ------------ ------------
>> ------------
>> 0 2.71 0.00320952 0.005 394.161
>> 0
>> 1 13.561367 0.45467 0.0131881 49.7247 129.098
>> 0.00108484
>> 2 2.5810166 0.2459 0.000347117 5.81263 30.6224
>> 0.00109655
>> 3 3.0946997 0.0073205 1.34869e-07 0.5504 3.18123
>> 5.13551e-05
>> 4 3.1139811 0.00033848 8.72888e-10 0.0214386 0.318187
>> 1.92754e-06
>> 5 3.1489261 0.00061552 2.90301e-09 0.018371 0.0318179
>> 3.49342e-06
>> 6 3.0091397 0.0024621 4.645e-08 0.0117079 0.00598559
>> 1.39742e-05
>> 7 2.710015 0.0068676 2.23731e-07 0.0199562 0.000603092
>> 2.99035e-05
>> 8 2.7116241 2.7338e-05 5.10117e-12 8.49417e-06 6.03182e-05
>> 1.60873e-07
>> 9 2.7101543 2.5902e-05 5.14787e-12 8.06346e-07 6.03182e-06
>> 1.46939e-07
>> 10 2.7100156 2.4442e-06 1.27526e-13 7.54021e-09 6.03182e-07
>> 1.3865e-08
>> Converged!
>>
>> Converged in 0.06 seconds
>> Objective Function Value = 2.71 $/hr
>> ================================================================================
>> | System Summary
>> |
>> ================================================================================
>>
>> How many? How much? P (MW) Q (MVAr)
>> --------------------- ------------------- -------------
>> -----------------
>> Buses 192 Total Gen Capacity 25.0 -25.0 to 25.0
>> Generators 4 On-line Capacity 25.0 -25.0 to 25.0
>> Committed Gens 4 Generation (actual) 3.5 1.7
>> Loads 73 Load 3.4 1.6
>> Fixed 72 Fixed 3.3 1.6
>> Dispatchable 1 Dispatchable 0.1 of 0.1 -0.0
>> Shunts 0 Shunt (inj) -0.0 0.0
>> Branches 191 Losses (I^2 * Z) 0.05 0.16
>> Transformers 191 Branch Charging (inj) - 0.0
>> Inter-ties 0 Total Inter-tie Flow 0.0 0.0
>> Areas 1
>>
>> Minimum Maximum
>> ------------------------- --------------------------------
>> Voltage Magnitude 0.957 p.u. @ bus 171 1.000 p.u. @ bus 1
>> Voltage Angle -2.53 deg @ bus 158 0.00 deg @ bus 1
>> P Losses (I^2*R) - 0.01 MW @ line 1-2
>> Q Losses (I^2*X) - 0.09 MVAr @ line 1-2
>> Lambda P 0.00 $/MWh @ bus 1 0.00 $/MWh @ bus 171
>> Lambda Q 0.00 $/MWh @ bus 1 0.00 $/MWh @ bus 171
>>
>>
>>
>>> On Jan 10, 2015, at 5:02 AM, Simone Cochi <[email protected]
>>> <mailto:[email protected]>> wrote:
>>>
>>> Dear all,
>>> I can’t get the convergence for the OPF on a radial distribution network
>>> described by the mpc file that I attached. The power flow with this case
>>> file converge and all the voltage busses are between without violating any
>>> costraints. The OPF doesn’t converge with the standard voltage constraints
>>> but if I relax them, the opf converge with voltage very high voltage
>>> levels. If I relax all the busses voltage constraints and I set Vmin=Vmax
>>> for the bus 1 (primary substation) the of converge and the voltage profiles
>>> are as expected. Can someone explain this behavior?
>>>
>>> Simone
>>> <mpc.mat>
>>
>
