Yes.
> On Apr 9, 2019, at 4:30 PM, Morteza Dabbaghjamanesh <[email protected]> wrote:
>
> Thank you very much for your reply, so if I set pf.enforce_q_lims equal to 1,
> it will do the PV-PQ switching?
>
> Sincerely,
>
>
> From: [email protected]
> <mailto:[email protected]>
> <[email protected]
> <mailto:[email protected]>> on behalf of Ray
> Zimmerman <[email protected] <mailto:[email protected]>>
> Sent: Tuesday, April 9, 2019 3:23:49 PM
> To: MATPOWER discussion forum
> Subject: Re: Using conventional parameters as variables in opf
>
> I could be wrong, but I would be very, very surprised if the near singular
> matrix issue is related to modeling the shunt susceptances as generators. The
> only other idea I have is to call the OPF iteratively as a subroutine with
> fixed shunt susceptances that you update according to your own optimization
> at each iteration.
>
> Regarding PV, PQ switching during the power flow, have a look at the
> pf.enforce_q_lims option (help mpoption or Table 4-2 or Table C-2 in the
> manual
> <https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.pserc.cornell.edu%2Fmatpower%2Fdocs%2FMATPOWER-manual-7.0b1.pdf&data=02%7C01%7Cmdabba1%40lsu.edu%7Cbe6b57a2516a472aca6708d6bd2aba4a%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C1%7C636904388546392475&sdata=2GlisEMkpTVah8NQ%2BQ2xredJyfy4evLEijO%2BtEe0%2FCU%3D&reserved=0>).
>
> Ray
>
>
>> On Apr 9, 2019, at 11:50 AM, Morteza Dabbaghjamanesh <[email protected]
>> <mailto:[email protected]>> wrote:
>>
>> Thanks for your reply. I have been able to fix the problem but can you
>> suggest any alternative way of converting the OPF parameters as variables
>> because I guess adding the shunt susceptances as generators is taking the
>> matrix close to singularity as I am getting some warning.
>>
>> One more question, does matpower do PV , PQ switching while solving the
>> Power Flow?
>>
>> Sincerely,
>>
>> From: [email protected]
>> <mailto:[email protected]>
>> <[email protected]
>> <mailto:[email protected]>> on behalf of Ray
>> Zimmerman <[email protected] <mailto:[email protected]>>
>> Sent: Tuesday, April 9, 2019 9:00:08 AM
>> To: MATPOWER discussion forum
>> Subject: Re: Using conventional parameters as variables in opf
>>
>> If it is not converging, it is likely (though not absolutely certain) that
>> the problem is infeasible. I suggest that you try turning on soft limits to
>> see if the OPF will converge with a few constraint violations. That can show
>> you which are the conflicting constraints. MATPOWER 7.0b1 has a much
>> improved soft-limit capability, so definitely get 7.0b1 if you don’t already
>> have it. See Section 7.6.4 in the MATPOWER User’s Manual
>> <https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.pserc.cornell.edu%2Fmatpower%2Fdocs%2FMATPOWER-manual-7.0b1.pdf&data=02%7C01%7Cmdabba1%40lsu.edu%7Cbe6b57a2516a472aca6708d6bd2aba4a%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C636904388546402480&sdata=aRd92GSt6LwObzhvexk6EEh0pzqrj%2FzlCMyzg9ex6oM%3D&reserved=0>
>> for more details on OPF soft limits.
>>
>> Then do …
>>
>> mpc = loadcase('<your case>');
>> mpc = toggle_softlims(mpc, 'on');
>> r = runopf(mpc);
>>
>> Oh, and by the way, PQ vs PV makes no difference for the OPF, only for the
>> power flow.
>>
>> Hope this helps,
>>
>> Ray
>>
>>
>>> On Apr 1, 2019, at 11:51 PM, Morteza Dabbaghjamanesh <[email protected]
>>> <mailto:[email protected]>> wrote:
>>>
>>> Hi,
>>>
>>> I have already set the Vmax and Vmin in mpc.bus section to Vg but the
>>> condition gets worse, the OPF is not converging now. Previously, though I
>>> have seen convergence but I have voltage violation almost in every buses of
>>> my system and this is also happening now. Do you have any idea why this is
>>> happening or how to get rid of this issue? Does switching from PQ to PV bus
>>> seems reasonable to you?
>>>
>>> If you can suggest some alternative way even it is difficult, it will be of
>>> great help to me.
>>>
>>> Regards,
>>>
>>>
>>> Get Outlook for iOS
>>> <https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Faka.ms%2Fo0ukef&data=02%7C01%7Cmdabba1%40lsu.edu%7Cbe6b57a2516a472aca6708d6bd2aba4a%7C2d4dad3f50ae47d983a09ae2b1f466f8%7C0%7C0%7C636904388546402480&sdata=sRB75kLk4FhtTJVSIYMBy6MJZyIa7ZsGArijAawD5h0%3D&reserved=0>
>>>
>>> From: [email protected]
>>> <mailto:[email protected]> on behalf of Ray
>>> Zimmerman <[email protected] <mailto:[email protected]>>
>>> Sent: Monday, April 1, 2019 5:25 PM
>>> To: MATPOWER discussion forum
>>> Subject: Re: Using conventional parameters as variables in opf
>>>
>>> There is not an easy way to convert a parameter (like shunt susceptance) to
>>> an OPF variable. The approach you are already taking is what I would
>>> suggest. It sounds like you may not have set VMIN and VMAX to the desired
>>> voltage (VG).
>>>
>>> On your second question, yes, the gencost matrix is always assumed to be
>>> ordered exactly the same as the gen matrix. That is, row i in one
>>> corresponds to row i in the other.
>>>
>>> Ray
>>>
>>>
>>>> On Apr 1, 2019, at 11:03 AM, Morteza Dabbaghjamanesh <[email protected]
>>>> <mailto:[email protected]>> wrote:
>>>>
>>>> Hi,
>>>>
>>>> I was wondering whether there is any way of converting a parameter into a
>>>> variable in OPF. Say for example, if I want to convert the shunt
>>>> susceptance which is usually passed as a parameter to the OPF , to a
>>>> variable, what is the easiest way of doing it.
>>>>
>>>>
>>>> Currently, I am considering shunts as reactive generators which can only
>>>> produce reactive power and no real power, to implement that, I have
>>>> appended new rows equal to the number of shunt buses in the generator
>>>> section of mpc data. Then I set the 'Pg','Pmax' and 'Pmin' to zero. I
>>>> collected the voltage from the bus data section and passed it to the 'Vg'
>>>> of the new added rows. I have also added some rows in the generator cost
>>>> section (appended at the last of the existing cost of the generators). I
>>>> have set the 'Qmax' and 'Qmin' from my maximum and minimum shunt
>>>> susceptance. I have also changed the bus types to 'PV' from 'PQ' mode (in
>>>> applicable cases). Though I am having an OPF solution but looking at the
>>>> results there are voltage limit violation in almost every buses. Can you
>>>> please suggest what could be the solution of this problem?
>>>>
>>>>
>>>> Another issue is, if I add any new generator to the power flow data, then
>>>> should I add the generator cost information at the end of the existing
>>>> generator cost or should I insert them as per the index of the generators.
>>>>
>>>> Best regards,
>>>> Morteza Dabbaghjamanesh
