I’m sorry, I’m trying to help you, but I can’t if you simply repeat your
request for me to explain how to modify the code, without ever answering my
question.
Which part of the code are you having trouble understanding?
Unfortunately, unless you can answer that, I’m afraid I can’t help you.
Ray
> On Oct 1, 2015, at 7:57 AM, Carlos Marta Gonzalez Almeida
> <[email protected]> wrote:
>
> Dear Prof. Zimmerman,
>
> I am really sorry about that. I really apologize for the way of writing. So
> sorry about that.
>
> Would you mind letting me know how I can modify the code in order to have
> variable power factor? I was not able to apply your comments. I'll be very
> grateful if you can help me please.
>
> Once again, I do apologize.
>
> Best regards,
>
> Carlos
>
> On Fri, Sep 25, 2015 at 6:34 PM, Ray Zimmerman <[email protected]
> <mailto:[email protected]>> wrote:
> Please do not keep asking us to provide you with the modifications to the
> code. You haven’t told us which part of that code you are having trouble
> understanding.
>
> There is a big difference between …
>
> 1. Can you please help me understand so I can do it? and …
> 2. Can you do it for me?
>
> I’m happy to try to do #1. I’m not interested in #2 (except possibly if hired
> as a consultant).
>
> Ray
>
>
>
>
>> On Sep 23, 2015, at 8:26 AM, Carlos Marta Gonzalez Almeida
>> <[email protected] <mailto:[email protected]>> wrote:
>>
>> Dear Dr. Zimmerman,
>>
>> What modifications I have to apply to the following code? Thanks
>>
>>
>>>>> ng = size(mpc.gen, 1);
>>>>> pf = 0.95;
>>>>> QPratio = sqrt(1/pf^2 -1);
>>>>> mpc.A = sparse([1:ng 1:ng]', [2*nb+(1:ng) 2*nb+ng+(1:ng)]',
>>>>> [QPratio*ones(ng,1); -ones(ng,1)], ng, 2*nb+2*ng);
>>>>> mpc.A = mpc.A(2:10, :);
>>
>>>>> mpc.l = zeros(ng-15, 1);
>>>>> mpc.u = mpc.l;
>>
>>>
>>>
>>> Best regards
>>>
>>> C
>>
>>
>> On Tue, Sep 22, 2015 at 2:25 PM, Ray Zimmerman <[email protected]
>> <mailto:[email protected]>> wrote:
>> That wouldn’t be correct anyway. The power factor is not the same as the Q/P
>> ratio. And you will need two separate sets of constraints, one for the upper
>> bound on the power factor and the other for the lower bound on the power
>> factor.
>>
>> Ray
>>
>>
>>
>>> On Sep 22, 2015, at 2:56 AM, Carlos Marta Gonzalez Almeida
>>> <[email protected] <mailto:[email protected]>> wrote:
>>>
>>> My problem is that I cannot implement matrix A in order to have
>>> -0.95*P<Q<P*0.95. What changes I have to apply to A matrix?
>>>
>>> Regards,
>>>
>>> Carlos
>>>
>>> On Mon, Sep 21, 2015 at 3:43 PM, Ray Zimmerman <[email protected]
>>> <mailto:[email protected]>> wrote:
>>> You really do need to understand what that code is doing before you can
>>> make modifications to make it do something else. So, to repeat my main
>>> question … is there a particular part of that code that you are having
>>> trouble understanding?
>>>
>>> It is setting up a constraint l <= A * x <= u, where x = [Va; Vm; Pg; Qg],
>>> so you need to define the A, l and u to restrict the Qg/Pg ratio in a way
>>> the enforces the power factor range you desire. You have an example of how
>>> to enforce the Qg/Pg ratio to a specific value that corresponds to a given
>>> power factor. Once you understand that, it should be trivial to get rid of
>>> the appropriate bound (l or u) to change it to an upper or lower bound on
>>> the power factor. Then you add a similar and opposite bound for another
>>> power factor value for the other end of your range.
>>>
>>> But, as I said … the first step is to fully understand the example you have.
>>>
>>> Ray
>>>
>>>
>>>
>>>> On Sep 21, 2015, at 2:37 AM, Carlos Marta Gonzalez Almeida
>>>> <[email protected] <mailto:[email protected]>> wrote:
>>>>
>>>> DEar Dr. Zimmerman,
>>>>
>>>> I don't know how I should change the equality constraint to inequality
>>>> constraint. I'll be very grateful if you can help me.
>>>>
>>>> Best regards,
>>>>
>>>> Carlos
>>>>
>>>> On Fri, Sep 18, 2015 at 4:12 PM, Ray Zimmerman <[email protected]
>>>> <mailto:[email protected]>> wrote:
>>>> Please address MATPOWER support questions (including followup’s to this
>>>> e-mail) to the MATPOWER mailing list
>>>> <http://www.pserc.cornell.edu/matpower/#mailinglist>.
>>>>
>>>> You simply have to change the equality constraint to an inequality
>>>> constraint. Is there a particular part of that code snippet that you are
>>>> having trouble understanding?
>>>>
>>>> Ray
>>>>
>>>>
>>>>> On Sep 1, 2015, at 11:58 AM, Carlos Marta Gonzalez Almeida
>>>>> <[email protected] <mailto:[email protected]>> wrote:
>>>>>
>>>>> Dear Dr. Zimmerman,
>>>>>
>>>>> According to your previous posts on the following equation which makes
>>>>> the power factor constant. Now I want to have power factor varying
>>>>> between -0.95 and 0.95. What changes to the following equation to be made?
>>>>>
>>>>> Thank you very much.
>>>>>
>>>>> Carlos
>>>>>
>>>>>
>>>>>
>>>>> ng = size(mpc.gen, 1);
>>>>> pf = 0.95;
>>>>> QPratio = sqrt(1/pf^2 -1);
>>>>> mpc.A = sparse([1:ng 1:ng]', [2*nb+(1:ng) 2*nb+ng+(1:ng)]',
>>>>> [QPratio*ones(ng,1); -ones(ng,1)], ng, 2*nb+2*ng);
>>>>> mpc.A = mpc.A(2:10, :);
>>>>> mpc.l = zeros(ng-15, 1);
>>>>> mpc.u = mpc.l;
>>>>
>>>>
>>>
>>>
>>
>>
>
>
>
