Re: CPF Question

[Aaqib Peerzada]

Hello Shri

Thanks for getting back.

 I'd like to make my situation more clear. My work involves scaling up the
all the loads in a power network in an incremental fashion up until the
power flow equations become unfeasible. So I progressively stress the
system by increasing all the loads through a load multiplier factor, lets
call it mu. As I do this, the system will not converge for some value of
mu, in case of 39 bus system, mu=1.239, which means the system collapses
when all loads are scaled up by a factor of 1.239 Now I'd like to plot the
nose curve (FULL) of any arbitrary bus using the CPF in MATPOWER. So
ideally what I want is bus voltage plotted with mu.

Can i get additional insights in to how can I modify the default callback
function keeping in view my requirements?

Thanks,
Aaqib

On Sun, Mar 5, 2017 at 12:22 PM, Abhyankar, Shrirang G. 
wrote:

> Hello Aaqib,
>   There is no in-built function in MATPOWER to plot what you need.
> However, you can do so easily in two ways:
>
>1. Modify the default callback function, cpf_default_callback.m, to
>plot the active power - voltage curve. Currently, it is set to plot
>lambda-voltage curve (both predicted and corrected).
>2. runcpf’s output struct stores all the states for each continuation
>step in its cpf field (results.cpf). You can use these values to create the
>active power-voltage curve.
>
> Hope this helps,
> Shri
>
> From: Aaqib Peerzada 
> Reply-To: MATPOWER discussion forum 
> Date: Friday, March 3, 2017 at 9:10 PM
> To: "matpower-l@cornell.edu" 
> Subject: CPF Question
>
> Dear Dr. Zimmerman and Friends
>
> I have a question regarding CPF in Matpower. In matpower the CPF algorithm
> plots the bus voltage against the continuation parameter (λ). However I'd
> like to plot the voltage against the active power at a bus(abscissa ). Is
> there any specific function that can let me do that or do i need to write
> some  additional code for accomplishing this?
>
> Thanks
>
> --
> *Aaqib A Peerzada*
>
>
>


-- 
*Aaqib A Peerzada*
*Graduate Student *
*Department of Electrical and Computer Engineering*
*Wisenbaker Engineering Research Center*
*Texas A&M University*
*College Station, Texas*
*United States.*
*Phone # 979-739-2799*
*Email: peerz...@tamu.edu *

Re: CPF Question

[Abhyankar, Shrirang G.]

Hello Aaqib,
  There is no in-built function in MATPOWER to plot what you need. However, you 
can do so easily in two ways:

  1.  Modify the default callback function, cpf_default_callback.m, to plot the 
active power - voltage curve. Currently, it is set to plot lambda-voltage curve 
(both predicted and corrected).
  2.  runcpf’s output struct stores all the states for each continuation step 
in its cpf field (results.cpf). You can use these values to create the active 
power-voltage curve.

Hope this helps,
Shri

From: Aaqib Peerzada mailto:peerz...@tamu.edu>>
Reply-To: MATPOWER discussion forum 
mailto:matpowe...@list.cornell.edu>>
Date: Friday, March 3, 2017 at 9:10 PM
To: "matpower-l@cornell.edu" 
mailto:matpower-l@cornell.edu>>
Subject: CPF Question

Dear Dr. Zimmerman and Friends

I have a question regarding CPF in Matpower. In matpower the CPF algorithm 
plots the bus voltage against the continuation parameter (λ). However I'd like 
to plot the voltage against the active power at a bus(abscissa ). Is there any 
specific function that can let me do that or do i need to write some  
additional code for accomplishing this?

Thanks

--
Aaqib A Peerzada

Re: Changes the reactance voltage values

[Abdulgader Alsharif]

Thanks a lot and appreciate it.

On 1 March 2017 at 20:17, Ray Zimmerman  wrote:

> [image: Boxbe]  This message is eligible
> for Automatic Cleanup! (r...@cornell.edu) Add cleanup rule
> 
> | More info
> 
>
> You can certainly use a Matlab for loop to run power flows to see the
> impact on losses over a range branch reactances. Just keep in mind that a
> reactance of zero will result in non-convergence, since it produces
> singular matrices.
>
> Regarding transformers, their data is included in the branch matrix,
> described in Table B-3 in the manual.
>
>Ray
>
>
> On Mar 1, 2017, at 12:36 AM, Abdulgader Alsharif <
> abdelkaderalsha...@gmail.com> wrote:
>
> And the last question is [how to use Transformers in MATPOWER?]
>
> If there is any explanation related to the above question, could
> you provide me the explanations?
>
>
> On 1 March 2017 at 07:54, Abdulgader Alsharif <
> abdelkaderalsha...@gmail.com> wrote:
>
>> Thanks a lot Dr.Ray,
>>
>> Indeed,  i made a printing mistake while i was writing an email, the
>> meaning of [reluctance] is (reactance*) is referring to branch reactance.
>>
>> But the one thing that i would know is , when i change the values of
>> reactance what i will get, Do i have to implement the same code?, an
>> example(0,0.01,0.02,0.031) which the changes should be incremental.
>>
>>  Best wishes.
>>
>> On 28 February 2017 at 20:47, Ray Zimmerman  wrote:
>>
>>> [image: Boxbe]  This message is
>>> eligible for Automatic Cleanup! (r...@cornell.edu) Add cleanup rule
>>> 
>>> | More info
>>> 
>>>
>>> I’m not sure what you mean by “reluctance voltage” and “reactance
>>> voltage”, but if you are referring to the branch reactance, then setting it
>>> to zero causes the Ybus matrix to become singular and the power flow fails.
>>> See the example below.
>>>
>>> Ray
>>>
>>>
>>> >> define_constants
>>> >> mpc = loadcase('case14');
>>> >> mpopt = mpoption('out.all', 0);
>>> >> r = runpf(mpc, mpopt);
>>>
>>> MATPOWER Version 6.1-dev, 21-Feb-2017 -- AC Power Flow (Newton)
>>>
>>> Newton's method power flow converged in 2 iterations.
>>> >> sum(real(get_losses(r)))
>>>
>>> ans =
>>>
>>>13.3933
>>>
>>> >> mpc.branch(14, BR_X) = 1e-5;
>>> >> r = runpf(mpc, mpopt);
>>>
>>> MATPOWER Version 6.1-dev, 21-Feb-2017 -- AC Power Flow (Newton)
>>>
>>> Newton's method power flow converged in 4 iterations.
>>> >> sum(real(get_losses(r)))
>>>
>>> ans =
>>>
>>>13.4047
>>>
>>> >> mpc.branch(14, BR_X) = 0;
>>> >> r = runpf(mpc, mpopt);
>>>
>>> MATPOWER Version 6.1-dev, 21-Feb-2017 -- AC Power Flow (Newton)
>>>
>>> Newton's method power flow did not converge in 10 iterations.
>>> >> sum(real(get_losses(r)))
>>>
>>> ans =
>>>
>>>NaN
>>>
>>>
>>>
>>> On Feb 28, 2017, at 12:07 PM, Abdulgader Alsharif <
>>> abdelkaderalsha...@gmail.com> wrote:
>>>
>>> Dear all
>>>
>>> I am Master student and a new in MATPOWER, using Matpower to find the
>>> losses in transmission lines (runpf) and how to change the reluctance
>>> voltage value in case14 as an example.
>>>
>>> Also, to find the daily PV load profile.
>>>
>>> Could you please help in writing Matlab code that change the reactance
>>> voltage values.
>>>
>>> I have tried with one but cannot working..
>>>
>>> NOTE:
>>> (r.branch(14,4)=0)
>>> when (14,4) is the position of the reactance value that i want to
>>> change, (0) is the initial changes will be incrementally.
>>>
>>> CODE
>>> for reactance (i) = Branchdata
>>> r.branch(14,4)=0
>>> end
>>>
>>>
>>> ​Already appreciated ..thanks to all​
>>>
>>> --
>>> ABDULGADER H. ABDULGADER ALSHARIF
>>> MASTER STUDENT AT ISTANBUL KEMERBURGAZ UNIVERSITY
>>> LIVE IN ISTANBUL-TURKEY
>>> Mobile phone Viber & whatsapp no. 00905454567238 <0545%20456%2072%2038>.
>>> Skype: abde