Regarding your first question, as described by (7.2) in the User’s Manual, the
reserve for a given generator is bounded above by both any limit provided in
mpc.reserves.qty (r_i^{max}) and by any physical ramp rate (∆_i) given in
mpc.gen(:, RAMP_10). It just so happens that the example in t_case30_userfcn
does not specify any physical ramp rates, but the code still needs to handle
cases which *do* provide physical ramp limits.
I’m not sure why you say only two generators are supposed to take part in the
reserve provision. In t_case30_userfcn there are two reserve zones defined, but
all 6 generators are able to participate in providing the required reserves.
You may want to review carefully the formulation in (7.2)–(7.5) and Table 7-2.
Ray
> On Mar 29, 2019, at 4:06 PM, Jubeyer Rahman <[email protected]> wrote:
>
> Referring to the 'userfcn_reserves_formulation', there is a line which is
> finding the value of k, which seems to be zero since none of the data in
> 'Ramp_10' column in t_case_30_userfcn is all zeros. so I don't see any point
> of using the line
>
> Rmax(k)=mpc.gen(k,Ramp_10), can you explain why the code is written that way.
>
> From my understanding only two generators are supposed to take part in the
> reserve provision, but the while putting the value for Rmax and Rmin, the
> code is considering all of them, which looks kind of unreasonable to me. Can
> you please explain this section as well?
>
> Regards,
> Jubeyer
>
> On Fri, Mar 29, 2019 at 12:43 PM Ray Zimmerman <[email protected]
> <mailto:[email protected]>> wrote:
> That is correct. All of the callbacks are technically optional. Typically you
> need the formulation callback to implement the actual problem modifications,
> and possibly ext2int and int2ext if you need to do some handling of input and
> output data, respectively. The printpf and savecase callbacks are only needed
> if you want to add things to the standard pretty-printed output or saved case
> data.
>
> Ray
>
>
>> On Mar 29, 2019, at 12:15 PM, Jubeyer Rahman <[email protected]
>> <mailto:[email protected]>> wrote:
>>
>> Just how important it is to include printpf and savecase callback during the
>> extension of OPF, if I don't really need anything printed out right after I
>> call the power flow? Will it be still possible to extract information from
>> the 'results' when I say results=runopf(mycase)?
>>
>> To my understanding, after runopf being called, 'results' struct will be
>> returned and can be accessed by writing some command like results.gen(:,2),
>> etc. Let me know if I am thinking correctly or not?
>>
>> On Fri, Mar 29, 2019 at 9:53 AM Jubeyer Rahman <[email protected]
>> <mailto:[email protected]>> wrote:
>> Thank you very much.
>>
>> On Fri, Mar 29, 2019 at 8:43 AM Ray Zimmerman <[email protected]
>> <mailto:[email protected]>> wrote:
>> Are you attempting to use the provided extension for fixed reserves, or are
>> you attempting to write your own extension?
>>
>> If it’s the former, the full implementation is included in toggle_reserves()
>> <http://www.pserc.cornell.edu/matpower/docs/ref/matpower6.0/toggle_reserves.html>.
>> Simply load your case file, use toggle_reserves() to enable the callbacks,
>> then run the OPF (or just call runopf_w_res()
>> <http://www.pserc.cornell.edu/matpower/docs/ref/matpower6.0/runopf_w_res.html>,
>> which does these 3 steps automatically for you).
>>
>> If you are attempting to write your own extension, I suggest making a copy
>> of toggle_reserves.m and rename it and all of the functions in it and use it
>> as a template for your own extension.
>>
>> Ray
>>
>>
>>> On Mar 28, 2019, at 12:40 PM, Jubeyer Rahman <[email protected]
>>> <mailto:[email protected]>> wrote:
>>>
>>> Hi,
>>>
>>> Recently I was digging through the extending OPF chapter of Matpower
>>> manual, but I don't quite catch the process. Regarding the example given
>>> there on 'Fixed zonal reserves' what I understand from my reading is, it is
>>> required to write down a call back function for formulation along with some
>>> call of callback functions. I have followed every steps mentioned there but
>>> could not make the code run (I am using version 6.0). I am adding my code
>>> snippet here for better conveying.
>>>
>>> %%%
>>> mpc=loadcase('case30.m');
>>> mpopt = mpoption('out.all', 0, 'verbose', 0);
>>> mpc=add_usefcn(mpc,'formulation',@userfcn_reserves_formulation);
>>> mpc=ext2int(mpc,mpopt);
>>> results=runopf(mpc);
>>> results=int2ext;
>>>
>>> %%%%
>>> Error message:
>>> Access to an object's fields is only permitted within its methods.
>>>
>>> I have added the mpc.reserve data(cost, req, zones) posted in
>>> 't_case30_userfcns.m' file.
>>> I have written the userfcn_reserves_formulation in a different script , but
>>> it is not working.
>>> I didn't write the add_var and add_constraint explicitly since the
>>> add_userfcn callback function already contains those.
>>>
>>> Can you tell me what I am missing?
>>>
>>> Regards,
>>> Jubeyer
>>>
>>
>
