Re: CPF stopping Criteria

2024-05-21 Thread Abhyankar, Shrirang G
Yes, CPF can stop at a given lambda value. For example, mpopt = mpoption; mpopt.cpf.stop=1.0 runcpf(‘case9’,’case9target’,mpopt); will stop the CPF when lambda reaches 1.0. Shri From: bounce-128220963-83436...@list.cornell.edu on behalf of Ahmad Sadiq Abubakar Date: Tuesday, May 21, 2024 a

Re: Question regarding Matpower's continuation power flow

2022-11-01 Thread Abhyankar, Shrirang G
Hi Carlos, Event: See MATPOWER manual section 5.5 for description of ‘events’ in MATPOWER. Basically, an event is a point on the continuation curve where some sort of limit or threshold is met. For example, a generator hitting its active/reactive power limit is an event. The full list of eve

Re: Base Case CPF - Reg

2021-09-21 Thread Abhyankar, Shrirang G
It is hard to say anything without knowing exactly what commands you ran. Please refer to the script on page 59 of the manual. Thanks, Shri From: on behalf of "A.K Samy" Reply-To: MATPOWER discussion forum Date: Tuesday, September 21, 2021 at 1:

Re: Request for technical data - Reg

2021-09-16 Thread Abhyankar, Shrirang G
The load real power (Pd) for a lambda value (lam) is given by Pd = (1-lam)*Pd_b + lam*Pd_t Where Pd_b and Pd_t are the load real powers for the base and target case, respectively. Similar calculation applies for reactive power. Shri From: on behalf of "A.K Samy" Reply-To: MATPOWER discussi

Re: Continuous power flow question

2021-06-01 Thread Abhyankar, Shrirang G
Hi Simone, See the FAQ on power flow divergence. It lists some useful tips to debug power flow divergence when using MATPOWER and how to run a continuation power flow to check if a power flow solution exists (point v). Thanks, Shri From: on beh

Re: Two questions

2020-07-06 Thread Abhyankar, Shrirang G
1. neg_dSd_dVm is a diagonal matrix having partial derivatives (negative) of the load injection (Sd) w.r.t. voltage magnitude (Vm). The load is described by a ZIP load, Sd = alpha_p(q) + alpha_i .* Vm + alpha_z .* Vm.^2 where alpha_p, alpha_i, and alpha_z are the load fractions for the consta

Re: CPF power flow did not converge

2019-07-11 Thread Abhyankar, Shrirang G
Cynthia, Please see this MATPOWER FAQ on debugging power flow divergence. Also, you forgot to attach your case file. Thanks, Shri From: on behalf of W Ruoyu Reply-To: MATPOWER discussion forum Date: Thursday, July 11, 2019 at 10:54 AM To: "MA

Re: Question about CPF

2019-07-02 Thread Abhyankar, Shrirang G
See below. Thanks, Shri From: on behalf of W Ruoyu Reply-To: MATPOWER discussion forum Date: Monday, July 1, 2019 at 5:35 PM To: MATPOWER discussion forum Subject: Re: Question about CPF Hi, Thanks for the reply ! That really helps. But I still have a little questions. To output the maximu

Re: Maximum load limit for radial distribution cases.

2019-06-13 Thread Abhyankar, Shrirang G
For maximum loadability calculations, it is best to run a continuation power flow (CPF) rather than power flow with successive load increments. CPF avoids ill-conditioning of the matrix near collapse point which a simple power flow cannot. One can run a CPF in MATPOWER using the runcpf() functio

Re: Question about power flow for a system with faulted bus

2019-06-05 Thread Abhyankar, Shrirang G
, CPF is widely used to solve low voltage problem. Any idea? Thank you once again. Ismael On Jun 1, 2019, at 7:38 AM, Abhyankar, Shrirang G mailto:shrirang.abhyan...@pnnl.gov>> wrote: Ismael, Power flow with loads modeled as “constant power” faces convergence issue when the voltages a

Re: Question about power flow for a system with faulted bus

2019-06-01 Thread Abhyankar, Shrirang G
Ismael, Power flow with loads modeled as “constant power” faces convergence issue when the voltages are low. A common trick is to convert constant power loads to constant impedance loads for low voltages. In MATPOWER, you can convert all the loads to constant impedance using the options 'exp.

Re: Continuation power flow_lambda

2019-05-12 Thread Abhyankar, Shrirang G
Lambda, a scalar quantity, represents the fraction of additional load/generation (transfer) on the network. The continuation power flow finds solutions starting from lambda = 0 (base loading/generation) to lambda_max (nose-point, max. loading/generation). You can translate the lambda value to a

Re: Isolated Bus - Power flow solution

2019-04-29 Thread Abhyankar, Shrirang G
John, MATPOWER’s power flow does not do a topology check to find isolated buses and islands. So, any isolated bus i needs to have its bus type set to None (4) -- mpc.bus(i, BUS_TYPE) = 4. If you want to find out which buses get isolated when the status of one or more lines changes then use th

Re: Removing a Bus and Evaluating the New Network

2019-04-29 Thread Abhyankar, Shrirang G
Mitchell, See below. Shri From: on behalf of "Dennis, Mitchell T." Reply-To: MATPOWER discussion forum Date: Friday, April 26, 2019 at 8:38 PM To: "MATPOWER-L@cornell.edu" Subject: Removing a Bus and Evaluating the New Network Dear All, I have a question regarding convergence. I am atte

Re: CPU time

2019-04-12 Thread Abhyankar, Shrirang G
Ahmad, Can you be more specific with your question. How big of a system are you planning to solve? Do you need to perform the CPF run within some stipulated time? CPF basically solves a series of power flow solutions given some transfer direction. Roughly, its computational complexity equal

Re: case300 problem

2019-04-12 Thread Abhyankar, Shrirang G
Naime, The bus numbers given in the casefile, “external bus numbers”, need not be consecutive integers from 1..nbus. These can be any integers. Internally, MATPOWER converts them to “internal numbering” (consecutive integers from 1..nbus). If you want to operate with internal numbers then us

Re: AC power flow not converge

2018-11-14 Thread Abhyankar, Shrirang G.
Hi, The AC power flow (runpf) is converging for your system, while the AC optimal power flow (runopf) does not. The reason being the line ratings (rateA, B, C) are less than the load they are supplying to. For instance, the load on bus 2 is 2.8 MW, but there is a single line 1-2 supplying pow

Re: Power Flow in Matpower

2018-03-16 Thread Abhyankar, Shrirang G.
See FAQ #5 Thanks, Shri Ph: (630) 252 0219 www.mcs.anl.gov/~abhyshr From: on behalf of Mohammed Alhajri Reply-To: MATPOWER discussion forum Date: Friday, March 16, 2018 at 11:26 AM To: MATPOWER discussion

Re: AC OPF Convergence Issue

2018-03-08 Thread Abhyankar, Shrirang G.
es to? There is no acceptable or unacceptable percentage. The line limits are relaxed simply to get the OPF to converge, but this may not be realistic for a practical solution. Shri sincerely, Aakanksha Dubey On Wed, Mar 7, 2018 at 7:25 PM, Abhyankar, Shrirang G. mailto:abhy...@anl.gov>>

Re: AC OPF Convergence Issue

2018-03-07 Thread Abhyankar, Shrirang G.
The voltage magnitudes in MATPOWER data files, (bus(:,VM)), are given in per unit and are generally close to 1.0. You have very low voltages for many of the buses. Similarly, the VMAX and VMIN values are also in per unit and generally they are 1.0 and 0.95, respectively. The following code resul

Re: Introducing contingency in the network

2018-01-17 Thread Abhyankar, Shrirang G.
ngency in the network ok and how can I find total generation like we find total load through total_load? On Wed, Jan 17, 2018 at 5:07 PM, Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> wrote: MATPOWER’s power flow does not enforce generator active power limits. To do so, run a dc optima

Re: load shedding by keeping load's power factor

2018-01-17 Thread Abhyankar, Shrirang G.
I don’t know of any straightforward way to do this in MATPOWER. You’ll need to add user-defined linear constraint to force the relationship between real and reactive power to keep the power factor constant. Turns out this question has already been addressed on the MATPOWER forum. https://www.mai

Re: Introducing contingency in the network

2018-01-17 Thread Abhyankar, Shrirang G.
MATPOWER’s power flow does not enforce generator active power limits. To do so, run a dc optimal power flow (rundcopf). Thanks, Shri Ph: (630) 252 0219 www.mcs.anl.gov/~abhyshr From: on behalf of Zain Anwer Memon Reply-To: MATPOWER discussion forum Date: We

Re: The question about extend OPF and the optimization tool

2018-01-17 Thread Abhyankar, Shrirang G.
Not sure if this is what you want, but here’s one way. https://www.mail-archive.com/matpower-l@cornell.edu/msg00613.html Thanks, Shri Ph: (630) 252 0219 www.mcs.anl.gov/~abhyshr From: on behalf of "neuqxhlin...@163.com" Reply-To: MATPOWER discussion forum Date

Re: Question about the continuation power flow

2017-12-28 Thread Abhyankar, Shrirang G.
The base case (with PD = QD = PG = 0) is not converging because some of the generators have high Qmin limits. You’ll also need to relax the generator Qmin limits for your base case. Thanks, Shri Ph: (630) 252 0219 www.mcs.anl.gov/~abhyshr From: on behalf of Youn

Re: PF did not converge

2017-12-14 Thread Abhyankar, Shrirang G.
Try the suggestions in FAQ #5 Thanks, Shri Ph: (630) 252 0219 www.mcs.anl.gov/~abhyshr From: on behalf of Mohammed Alhajri Reply-To: MATPOWER discussion forum Date: Thursday, December 14, 2017 at 11:55

Re: How to find max-load ability for each bus of power system

2017-11-30 Thread Abhyankar, Shrirang G.
ility of bus i, for voltage stability of power system. In other words, does it mean that bus is critical for voltage stability studies? On Mon, Nov 27, 2017 at 11:22 PM, Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> wrote: Hello, MATPOWER’s CPF requires two data files; the first one having th

Re: How to find max-load ability for each bus of power system

2017-11-27 Thread Abhyankar, Shrirang G.
Hello, MATPOWER’s CPF requires two data files; the first one having the base loading/generation, called basecasedata, and the other that has the target loading/generation, called targetcasedata. The CPF traces the trajectory of solutions along increasing lambda direction, with lambda = 0 at th

Re: PF and OPF did not converge

2017-10-03 Thread Abhyankar, Shrirang G.
http://www.pserc.cornell.edu/matpower/#pfconvergence From: on behalf of Charalambos Ioannou Reply-To: MATPOWER discussion forum Date: Tuesday, October 3, 2017 at 9:12 AM To: "MATPOWER-L@cornell.edu" Subject: PF and OPF did not converge Dear Ray, I am trying to run PF and OPF for the foll

Re: Tap ratios set to 0, run OPF with tap changers

2017-09-25 Thread Abhyankar, Shrirang G.
Dear Matpower users, I have some questions about tap ratios in Matpwer. What does it mean if the tap ratios TAP are set to 0? Tap ratio=0 is used to indicate that the branch is a non-transformer branch, while 1 indicates a transformer branch. Even if you set the tap ratio = 0 for a transformer

Re: branch_lims

2017-08-03 Thread Abhyankar, Shrirang G.
That's great! This would be a good addition to runcpf. You can contribute directly to MATPOWER https://github.com/MATPOWER/matpower/blob/master/CONTRIBUTING.md. Alternately, you can send me (cc Ray) the code offline. Thanks, Shri On Aug 3, 2017, at 1:35 AM, Ahmad Sadiq Abubakar mailto:ahmad.abu

Re: Calculation of r, x, b from PF results

2017-08-03 Thread Abhyankar, Shrirang G.
This is an inverse problem. You'll need to use a nonlinear least squares solver (lsqnonlin in MATLAB) to compute the line parameters given the different measurements. MATPOWER does not have an explicit function to do what you want, but you can use its different functions (or extract code from th

Re: Objective Functions

2017-07-15 Thread Abhyankar, Shrirang G.
MATPOWER supports two types of generator cost curves: quadratic and piece-wise linear. I don’t think there is support for user-defined cost curves, Ray would be able to provide a more definitive answer. So, I think there is an no easy way to implement the objective you need. You’ll need to modif

Re: Get_losses

2017-07-15 Thread Abhyankar, Shrirang G.
dloss_dv is the partial derivative of the losses w.r.t. voltage angle. It is an optional output argument. If you do not need it then don’t use it. FYI: MATPOWER has an online function reference where you can see the usage of all of its functions.

Re: Compare case

2017-07-15 Thread Abhyankar, Shrirang G.
compare_case() cannot be used on two different networks. It compares the runpf() (or runopf()) outputs for two different scenarios on the “same” network. For example, mpc1 = runpf(‘case9’);% run power flow on 9-bus network mpc2 = loadcase(‘case9’);% load 9-bus network mpc2.branch(8,11

Re: multi-period AC Power Flow (not OPF)

2017-07-15 Thread Abhyankar, Shrirang G.
Using a loop would be the easiest way. Alternately, you could concatenate all the mpc bus, gen, etc. arrays into one giant mpc case and then solve it via a single runpf(). However, this is more complicated (changing of bus,gen, branch numbers for the later time-steps) compared to using a loop.

Re: CPF Callback Functions

2017-07-05 Thread Abhyankar, Shrirang G.
Here’s an example of a CPF call back function. The callback function can be set through MATPOWER options struct mpopt = mpoption(mpopt

Re: Load increase in one busbar using runcpf

2017-05-14 Thread Abhyankar, Shrirang G.
Assuming 101 is the row number in the mpc.bus array for bus 101: define_constants; mpopt = mpoption('out.all', 1, 'verbose', 2); mpopt = mpoption(mpopt, 'cpf.stop_at', 'FULL', 'cpf.step', 0.2,’cpf.plot.bus’,101); mpopt = mpoption(mpopt, 'cpf.plot.level', 2); mpcb = loadcase('Case_04'); % load bas

Re: CPF termination

2017-05-10 Thread Abhyankar, Shrirang G.
of implementing this in similar manner as the cpf.enforce_q_lims. Kindly advice On May 10, 2017 5:25 PM, "Abhyankar, Shrirang G." mailto:abhy...@anl.gov>> wrote: Hi Ahmad, If you are referring to cpf_default_callback.m then NO, you do need to modify it. The callback function(s

Re: CPF termination

2017-05-10 Thread Abhyankar, Shrirang G.
e default callback function for cpf termination? Kindly excuse my too basic questions, I am novice in coding. In anticipation of your reply On Apr 25, 2017 6:45 PM, "Abhyankar, Shrirang G." mailto:abhy...@anl.gov>> wrote: Ahmad, You need to implement an event function (see s

FW: MATPOWER, 9 bus System, Need help solving

2017-04-29 Thread Abhyankar, Shrirang G.
Dear Saad, It is always best to send your querries on the MATPOWER mailing list than to direct it to individual members. You will multiple and much better responses by mailing the list. I don’t think MATPOWER has a function that can do the state estimation as you’ve described in the document.

Re: CPF termination

2017-04-25 Thread Abhyankar, Shrirang G.
Ahmad, You need to implement an event function (see section 5.5 of the manual) for cpf with logic on how you want cpf to terminate. There are a few event functions currently implemented — nose point detection, target limit, active/reactive power limits — but there is no user-defined event func

Re: Line loading limit

2017-04-19 Thread Abhyankar, Shrirang G.
ilto:matpowe...@list.cornell.edu>> Date: Wednesday, April 19, 2017 at 1:32 AM To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Subject: Re: Line loading limit and what in case of 'rundcopf' On Wed, Apr 19, 2017 at 11:39 AM, Abhyankar, Shrirang G. mailto:abhy...@anl.g

Re: Line loading limit

2017-04-18 Thread Abhyankar, Shrirang G.
runpf does not enforce any line limits. You need to run optimal power flow (runopf). Shri From: Akash Tyagi mailto:akashtyagi0...@gmail.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Date: Tuesday, April 18, 2017 at 9:57 PM To: MATPOWER discussion forum mailto:m

Re: regarding CPF

2017-04-13 Thread Abhyankar, Shrirang G.
I think the base case has the generator at bus 8 turned off, while the target case has it ON. My guess is this is causing problems in the CPF when creating the transfer vectors due to differences in sizes of the Pg/Qg. Can you keep the generator ON at bus 8 in the base case with zero real and re

Re: False Data Detection in State Estimation

2017-04-02 Thread Abhyankar, Shrirang G.
MATPOWER assumes the network is balanced so only a positive sequence power flow calculation is performed for transmission and distribution. If you’d like to do an unbalanced distribution power flow calculation then you’ll need to use other tools like OpenDSS or GridLab-D. Shri From: Akash Tyag

Re: Continuation Power Flow - Target case data

2017-04-02 Thread Abhyankar, Shrirang G.
The target case lets one set the power transfer direction along which the steady state loading limit needs to be determined. Different target generation/loading will yield different nose points. Shri From: Sanjay Rajendran mailto:sanjay.rajendran0...@gmail.com>> Reply-To: MATPOWER discussion f

Re: CPF Question

2017-03-06 Thread Abhyankar, Shrirang G.
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. mailto:abhy...@anl.gov>> wrote: Hello Aaqib, There is no in-built function in MATPOWER t

Re: CPF Question

2017-03-05 Thread 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 predic

Re: CPF with Matpower

2017-03-02 Thread Abhyankar, Shrirang G.
: Corrector did not converge in 10 iterations", suppose in the attached <https://drive.google.com/open?id=0BzHW_Oh9YrAfY0gwQ0xTNGJHVzg> case (modified 14 bus case, only the line impedances are changed). So in this case is there anyway I can increase the number of steps for the c

Re: CPF with Matpower

2017-02-27 Thread Abhyankar, Shrirang G.
ed <https://drive.google.com/open?id=0BzHW_Oh9YrAfY0gwQ0xTNGJHVzg> case (modified 14 bus case, only the line impedances are changed). So in this case is there anyway I can increase the number of steps for the cpf? Thanks Mahi On Wed, Feb 22, 2017 at 11:16 AM, Abhyankar, Shrirang G. mailto:a

Re: bus view

2017-02-24 Thread Abhyankar, Shrirang G.
Try http://immersive.erc.monash.edu.au/stac/ Shri From: Matt Carmell mailto:matt.carm...@scylla-energy.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Date: Friday, February 24, 2017 at 12:21 PM To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> S

Re: CPF with Matpower

2017-02-22 Thread Abhyankar, Shrirang G.
Hello Mahi, basecasedata is a MATPOWER data struct that has the base case loading/generation, while targetcasedata has that for the target loading/generation. A continuation power flow traces power flow solutions starting from the base case to the target case, if it can be reached. Please see

Re: load reduction in continuation power flow (CPF)

2017-02-16 Thread Abhyankar, Shrirang G.
I agree with Ray. The base case dispatch being updated by OPF causes a reduction in generation, commensurate to the load reduction, and hence you are seeing a decrease in the load margin. What happens when you decrease the load at some other buses? Do you get the same behavior? Shri From: Ray

Re: AW: Bus Voltage Constraints

2017-01-27 Thread Abhyankar, Shrirang G.
You can make an OPF mimic a PF by relaxing the constraints (line flow, voltage constraints) and setting the cost function to zero. (by setting values in mpc.gencost = 0) Shri From: siddique tomal mailto:siddiquetoma...@gmail.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cor

Re: runpf help

2016-10-05 Thread Abhyankar, Shrirang G.
results=runpf(this_case,mpopt); J=full(makeJac(results)); > On Oct 5, 2016, at 6:05 PM, Aaqib Peerzada wrote: > > results=runpf(this_case,mpopt); > J=full(makeJac(this_case));

Re: Problem with runcpf

2016-09-08 Thread Abhyankar, Shrirang G.
20759695-68616...@list.cornell.edu> mailto:bounce-120759695-68616...@list.cornell.edu>> de la part de Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> Envoyé : mercredi 7 septembre 2016 14:16 À : MATPOWER discussion forum Objet : Re: Problem with runcpf Are you sure the OPF converged? If it did, the

Re: Problem with runcpf

2016-09-07 Thread Abhyankar, Shrirang G.
-120746902-68616...@list.cornell.edu<mailto:bounce-120746902-68616...@list.cornell.edu> mailto:bounce-120746902-68616...@list.cornell.edu>> de la part de Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> Envoyé : vendredi 2 septembre 2016 13:42 À : MATPOWER discussion forum Objet

Re: Problem with runcpf

2016-09-02 Thread Abhyankar, Shrirang G.
I suspect you have isolated buses or islands that do not have a swing bus. Have you tried I-iv in MatPower faq on power flow divergence. http://www.pserc.cornell.edu/matpower/#pfconvergence Shri On Sep 2, 2016, at 6:51 AM, Gamze Dogan mailto:gamgam...@hotmail.com>> wrote: Dear all, I have a

Re: Admittance formula for branches with transformers

2016-08-26 Thread Abhyankar, Shrirang G.
Please take a look at the function makeYbus(). > On Aug 26, 2016, at 10:05 AM, davor sutic wrote: > > I'm trying to understand the effects of having a transformer connected to a > branch on the implicated admittance matrix. In the MatPower manual, section > 3.2, equation 3.2 describes such a

Re: How do I print the reduced Ybus matrix

2016-07-27 Thread Abhyankar, Shrirang G.
1. You need to have the MATPOWER directory on your MATLAB path. http://www.mathworks.com/help/matlab/matlab_env/add-remove-or-reorder-folders-on-the-search-path.html 2. YBUS, YF, YT] = makeYbus(mpc) should be YBUS, YF, YT] = makeYbus(mpcreduced); Shri From: Philip Adedotun Olaniyi mailto:pola

Re: How do I print the reduced Ybus matrix

2016-07-27 Thread Abhyankar, Shrirang G.
Use makeYbus() to create the admittance matrix for the reduced network. http://www.pserc.cornell.edu/matpower/docs/ref/matpower5.0/makeYbus.html Shri On Jul 26, 2016, at 10:19 PM, Philip Adedotun Olaniyi mailto:polan...@unm.edu>> wrote: Good day sir, I am trying to extract the reduced Y matri

Re: Query about LMP function

2016-06-29 Thread Abhyankar, Shrirang G.
http://www.pserc.cornell.edu//matpower/docs/ref/matpower6.0b1/scale_load.ht ml FYI: The list of available MATPOWER functions can be found here http://www.pserc.cornell.edu//matpower/docs/ref/ Shri From: Priyanka Shinde Reply-To: MATPOWER discussion forum Date: Wednesday, June 29, 2016 at

Re: AW: CPF - Functionality

2016-06-10 Thread Abhyankar, Shrirang G.
xfr is. Important is only the relation between the different rows of the vector? Thomas Von: bounce-120551126-75986...@list.cornell.edu<mailto:bounce-120551126-75986...@list.cornell.edu> [mailto:bounce-120551126-75986...@list.cornell.edu] Im Auftrag von Abhyankar, Shrirang G. Gesendet: Donners

Re: CPF - Functionality

2016-06-09 Thread Abhyankar, Shrirang G.
1. Yes. 2. CPF with generator active and reactive power limits should be hopefully available in the upcoming version of MATPOWER. Checking for min. or max. bus voltages is not available in CPF. With some modifications in the CPF code, you should be able to check voltages. We were working on user

Re: Wind generation

2016-05-22 Thread Abhyankar, Shrirang G.
No. > On May 22, 2016, at 5:25 PM, Mohamed Taleb wrote: > > Dears, > > Greetings, > I there any modeling for the wind turbine that simulates its behavior? > > Regards, > Mohamed Taleb

Re: modification on Matpower case.m file for power flow of distribution system

2016-05-04 Thread Abhyankar, Shrirang G.
http://ewh.ieee.org/soc/pes/dsacom/testfeeders/index.html However, as Jovan mentioned, MATPOWER is for solving balanced three-phase transmission systems. If you are interested in solving unbalanced three-phase power flows for distribution networks then refer to either OpenDSS or GridLAB-D. Shri

Re: scaleload

2016-02-23 Thread Abhyankar, Shrirang G.
mpc=loadcase('case14o’); for t=1:2 mpc(t)=mpc; mpc(t).bus = scale_load(0.5, mpc(t).bus); The error is in the third line of your code. You are resizing the mpc struct created in the first line and hence getting the structure resizing error. Use the following code. mpc0=loadcase('c

Re: power flow question

2016-02-18 Thread Abhyankar, Shrirang G.
I agree. Having the warnings for all generators, voltages, etc. would be helpful for the cases when users are also varying the generation on PV buses. I would even like MATPOWER fixing the active power at PV buses to the max. or min. limit, if the generation exceeds these limits, and informing t

Re: power flow question

2016-02-17 Thread Abhyankar, Shrirang G.
Wenlei, The power flow routine in MATPOWER does not enforce generation limits on real power. Exceeding the capacity does not necessarily imply a divergence of the power flow. Shri From: , Wenlei mailto:wenlei_...@baylor.edu>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell

Re: price sensitive loads

2016-02-16 Thread Abhyankar, Shrirang G.
The file name needs to be a string. mpc = load2disp(mpc0,’mo’); From: VANJARAPU VENKATARAONAIDU mailto:venkataraovanjar...@gmail.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> List-Post: matpower-l@cornell.edu Date: Tuesday, February 16, 2016 at 7:47 AM To: "MAT

Re: Generating Larger Test Cases from existing Matpower Cases

2016-02-15 Thread Abhyankar, Shrirang G.
Paul, To add to this discussion, I recall Carlos mentioning that one needs to be careful when trying to ³stitch² together different systems due to the large angle differences at the interconnection buses, which might lead to solver infeasibility. The following email threads might be helpful in

Re: demand response

2016-02-14 Thread Abhyankar, Shrirang G.
Please ALWAYS send the code you were trying to run and the entire error message. Shri On Feb 13, 2016, at 11:16 PM, Mounika Vanjarapu mailto:mounikavanjar...@gmail.com>> wrote: when i tried for case9 or case5 ,its getting error.what is the reason On Wed, Feb 10, 2016 at 6:29 PM, Mounika Vanjar

Re: save losses

2016-02-13 Thread Abhyankar, Shrirang G.
The two error messages you’ve sent look unrelated to me. Are these from two different runs? In any case, most likely, you are using an older version of MATPOWER. Download the latest version from here http://www.pserc.cornell.edu//matpower/. If you are still getting errors, please send the “enti

Re: How to model a substation in Matpower

2016-02-12 Thread Abhyankar, Shrirang G.
Dear Matpowers, Hope you are doing great. We are trying to run PF for a distribution network in Matpower. Since the R/X ratio is acceptable we tried NR. It did converge, however, the loss is not correct. The loss formulae used in MATPOWER are given in section 9.2.4 of the manual http://www.ps

Re: demand reponse

2016-02-02 Thread Abhyankar, Shrirang G.
; which way i can know which is most preferrable outage by contingency analysis using matpower. On Tue, Feb 2, 2016 at 10:18 PM, Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> wrote: Each generator, branch has a status that you can change to simulate a contingency. See the functions idx_

Re: demand reponse

2016-02-02 Thread Abhyankar, Shrirang G.
Each generator, branch has a status that you can change to simulate a contingency. See the functions idx_brch() and idx_gen() for the appropriate columns for the status flag in the branch and generator data, respectively. Shri From: Mounika Vanjarapu mailto:mounikavanjar...@gmail.com>> Reply-T

Re: Question about islands.

2016-01-21 Thread Abhyankar, Shrirang G.
Mirish, Before moving further, I would suggest you to review the practicality of the assumptions you are making. 1) Does it make sense to move the loads, generation to a higher voltage level? 2) For a utility engineer working on a real system, would he/she add dummy branches to make the analy

Re: How to Show Voltage Constraints and Branch Flow Constraints

2016-01-07 Thread Abhyankar, Shrirang G.
You are running a power flow (runpf), not an optimal power flow (runopf). The branch limits (and the voltage constraints) are ignored for power flow calculations. If the power flow does not converge then most likely the optimal power flow may not converge either. Please take a look at http://ww

Re: Running Available Transfer Capability (ATC-Power System)

2016-01-04 Thread Abhyankar, Shrirang G.
The number of input arguments to runpf() is incorrect. Please send the error log (output in the command window). Shri From: abde wahab naser mailto:abdewahab_na...@yahoo.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Date: Monday, January 4, 2016 at 5:11 AM To:

Re: ask in matpower 3.2

2015-12-31 Thread Abhyankar, Shrirang G.
You can calculate the branch currents (from and to end) using the real and reactive power flows (from the branch data) and the bus voltages (in the bus data). See the function idx_brch() and idx_bus() for the location of the flows and voltages. Shri From: Mahmoud Abdallah mailto:mahmoud_abdal

Re: Difference between System and Load Losses

2015-12-29 Thread Abhyankar, Shrirang G.
Arun, I don’t think there is a “load losses” function in MATPOWER that returns how much load is lost akin to a LOLE calculation. If you want to calculate loss of load for reliability or restoration calculations, then you can run an optimal power flow with dispatchable loads. (set very high pri

Re: 39-bus system

2015-12-20 Thread Abhyankar, Shrirang G.
Yes. However, note that each area needs to have enough generation capacity to supply the load. Shri > On Dec 19, 2015, at 12:42 PM, "Owusuboateng, Prince Charles" > wrote: > > Hello, > > I have the 39 bus system divided into 4 independent areas. Can I run > individual optimal power flow ana

Re: Continuation Power Flow

2015-12-02 Thread Abhyankar, Shrirang G.
You need to create a callback routine for CPF that plots what you need and set it in the options struct. mpopt = mpoption(‘cpf.user_callback’,’cpf_user_callback’); where cpf_user_callback is the name of your callback routine. Read pages 38 - 40 of the manual. Shri From: Anjali Sharma mailto

Re: ACOPF constraints

2015-11-30 Thread Abhyankar, Shrirang G.
Rectangular. > On Nov 30, 2015, at 5:10 AM, "Vladimir Frolov" > wrote: > > Dear Matpower community, > > Do you know if opportunity cost constraint is used in the ACOPF formulation > of Matpower? > In other words, does an allowed P,Q area for generator is just a rectangular > with Pmax, Pmin,

Re: Question about sparsity-based implementation in MATPower

2015-10-20 Thread Abhyankar, Shrirang G.
tle or no advantage to PARDISO, and the extra overhead was noticeable on small systems. Ray On Oct 19, 2015, at 1:05 AM, Shruti Rao mailto:sra...@asu.edu>> wrote: Thank you Dr. Abhyankar for the guidance. I appreciate your time and effort. Shruti On Sun, Oct 18, 2015 at 10:02 PM

Re: VSC-Multiple Terminals

2015-10-20 Thread Abhyankar, Shrirang G.
You can run a load flow with MATPOWER, but it does not have small signal analysis capability yet. Shri On Oct 20, 2015, at 12:08 PM, "Rajesh Vaid" mailto:umv...@myumanitoba.ca>> wrote: Hello Matpower community, I am working on DC grid system where in the system is based on multiple VSC= con

Re: Question about sparsity-based implementation in MATPower

2015-10-18 Thread Abhyankar, Shrirang G.
that MATpower uses "\" right? Thank you for your response. On Sun, Oct 18, 2015 at 6:27 PM, Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> wrote: Hi Shruti, The direct linear solver used by MATLAB depends on the symmetry of the Jacobian matrix. For MATPOWER test cases tha

Re: Question about sparsity-based implementation in MATPower

2015-10-18 Thread Abhyankar, Shrirang G.
Hi Shruti, The direct linear solver used by MATLAB depends on the symmetry of the Jacobian matrix. For MATPOWER test cases that have symmetric Jacobians (due to inactive taps), a Cholesky factorization is used (LL^T = A). For cases that lead to non-symmetric Jacobian, MATLAB uses UMFPACK for p

Re: Computing "A" matrix for Eigenvalue analysis

2015-09-29 Thread Abhyankar, Shrirang G.
I think you want to calculate the eigen values the Jacobian matrix for the AC-DC power flow. You need to get in touch with MATACDC developers to find out what API is provided for obtaining the Jacobian matrix. MATPOWER has the function makeJac() http://www.pserc.cornell.edu/matpower/docs/ref/matpow

Re: Constraint types and its effect on OPF convergence

2015-09-10 Thread Abhyankar, Shrirang G.
I am not sure there is a clear obvious way to tell which constraints pose the most problem for the optimization. Perhaps doing some sensitivity analysis might help, but with different operating conditions you will get different sensitivities. There are a few papers published on convergence behav

Re: Jacobian matrix

2015-09-07 Thread Abhyankar, Shrirang G.
The size of the square Jacobian matrix, returned by makeJac(), in MATPOWER is 2*npv + npq, where npv is the number of PV buses and npq is number of PQ buses. You can create appropriate permutation vectors to reorganize the matrix entries. However, from what I understand, you want to put the entries

Re: REQUEST

2015-09-03 Thread Abhyankar, Shrirang G.
ornell.edu>> de la part de Abhyankar, Shrirang G. mailto:abhy...@anl.gov>> Envoyé : 2 septembre 2015 08:24 À : MATPOWER discussion forum Objet : Re: REQUEST What do you mean by 'simple (direct or undirect) network'? Shri On Aug 31, 2015, at 9:06 PM, "Mohamed-Larbi R

Re: REQUEST

2015-09-02 Thread Abhyankar, Shrirang G.
What do you mean by 'simple (direct or undirect) network'? Shri On Aug 31, 2015, at 9:06 PM, "Mohamed-Larbi Rebaiaia" mailto:mohamed-larbi.rebaiai...@ulaval.ca>> wrote: Hi... I would like to proceed to the transformation of an electric network ( e.g. Network39bus​) into a simple (direct or

Re: REQUEST

2015-08-31 Thread Abhyankar, Shrirang G.
usuboateng, Prince Charles" mailto:powusuboateng8...@mytu.tuskegee.edu>> wrote: Please it has not been of help. I am looking to load each of the 4 regions independently and perform power flows on each one of them. On Mon, Aug 31, 2015 at 2:58 PM, Abhyankar, Shrirang G. mailto:ab

Re: REQUEST

2015-08-31 Thread Abhyankar, Shrirang G.
Please take a look at the continuation power flow chapter in the MAtPOWER manual. Shri On Aug 31, 2015, at 11:05 AM, "Owusuboateng, Prince Charles" mailto:powusuboateng8...@mytu.tuskegee.edu>> wrote: Hi All, I have a divided the IEE 39bus system in 4 areas. I will like to load each of the 4

Re: transformers and tap coefficients

2015-08-26 Thread Abhyankar, Shrirang G.
Yes, it is a typo. It should be r =b =0. Shri > On Aug 26, 2015, at 6:47 AM, "Vladimir Frolov" > wrote: > > Dear Matpower community, > > My question is about tap coefficients. It is said in the data description > that branch includes transformer if r=x=0. But actually in cases r and b =0. >

Re: About three winding transformers and contingency analysis

2015-08-23 Thread Abhyankar, Shrirang G.
It would be hard to find which branches in the MATPOWER data constitute a three-winding transformer if you don’t have the original cases. I guess you’ll just have to choose sets of three branches and assume they constitute three-winding transformers. Shri From: Jesus Maria Lopez Lezama mail

Re: Add a load as a variable to the extended optimal power

2015-08-21 Thread Abhyankar, Shrirang G.
See section 6.4.2 on ‘dispatchable loads’ in the MATPOWER manual. Shri From: Mahdi Kiaee mailto:meh19...@yahoo.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Date: Friday, August 21, 2015 at 1:35 PM To: "MATPOWER-L@cornell.edu" mail

Re: Matpower Opf with tap changer

2015-08-20 Thread Abhyankar, Shrirang G.
Here’s a relevant discussion from the MATPOWER mail archive. https://www.mail-archive.com/matpower-l@cornell.edu/msg04162.html Shri From: "Chen, Hengsi" mailto:h...@iaew.rwth-aachen.de>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Date: Thursday, August 20, 2015 at

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