RE: PQ Capability HVDC Converter
Hi Uriel, thank you for your answer. I saw in the user manual under point 7.5.3 DC Transmission lines that DC Lines are implemented with Dummy Generators. I would assume that these dummy Generators can be seen in general as Converters. So, I think I just have to put constraints on these dummy generators. But where are these constraints defined or in other words: are there already constraints at all? What do you think about my thoughts? Would you agree? From: uriel_sando...@ieee.org Subject: Re: PQ Capability HVDC Converter Date: Mon, 3 Nov 2014 07:02:30 -0600 To: matpowe...@list.cornell.edu Hi Christian, As far as i know, matpower does not include FACTS devices (such HVDC), you will have to code it. Best regards, Uriel El 03/11/2014, a las 6:51, Christian Orberger christian.orber...@outlook.com escribió:Hello, I want to extend the P-Q constraints of an HVDC Converter in the OPF in Matpower. My question is, if there already are any constraints regarding these converters in the OPF and if yes, where I can find them in the programm? Or do I have to implement completely new constraints? Thank you for your help! Best regards, Christian
Re: incorporating N-1 contingency
MATPOWER does not include a facility for automatic N-1 contingency analysis. You can however, implement your own brute force checking of contingencies by, one-by-one, changing the status to zero (mpc.branch(k, BR_STATUS) or mpc.gen(k, GEN_STATUS)) on the line or generator taken out by the contingency in question. Beware of creating isolated buses or islands when taking out lines. The find_islands() function may be helpful there. -- Ray Zimmerman Senior Research Associate B30 Warren Hall, Cornell University, Ithaca, NY 14853 USA phone: (607) 255-9645 On Nov 2, 2014, at 7:25 AM, abhisek mishra abhisek005mis...@gmail.com mailto:abhisek005mis...@gmail.com wrote: Dear all, I am a new user of matpower. Can anyone guide me in how to incorporate N-1 contingency using matpower??? Thank you. Abhisek
Re: Help with incomplete real case data
I agree with Uriel that many of these parameters cannot simply be assumed without more information about the system. You can make up numbers, but the OPF results will be garbage. I think you need more information. Ray On Nov 3, 2014, at 8:55 AM, Zeya Aung [11547809d] zya@connect.polyu.hk wrote: Thanks Ureil! Do you have some reference to support the Qmin= -1/3 Qmax assumption? If it is a good approximation used in the industry, i think it’s justified to make this assumption in my project. What do you think should i assume the values of RateA B C for the Matpower case format branch data? Many thanks. Will appreciate if anyone else has some comments on my 4 problems. Best Zeya On 3 Nov, 2014, at 9:22 pm, Uriel Fernando Sandoval uriel_sando...@ieee.org wrote: Hi Zeya, I’ll try to answer some of your questions: 1) Reactive power consumption (Qmin) is typically smaller than Qmax. Sometimes a good approximation is to take Qmin= -1/3 Qmax, but to a better assumptions you have to look at the generator’s capability curve. 2) If you are doing PF analysis you don’t need these parameters. But in my opinion the line’s capacity typically are between 25-1000 MW. This parameter depends on the physical construction of the line and i think you can’t assume it. 3) The best way is to use either pice-wise or quadratical convex functions. If you have a set of points that represent the generator cost under different powers, you can approximate this set to a quadratical function using least squares regression. 4) This data is very important and you should not assume it. if you can obtain the cost functions you should run an OPF to dispatch active power generation and then you will have a base case to perform all your steady state analysis. Best regards, Uriel El 02/11/2014, a las 14:09, Zeya Aung [11547809d] zya@connect.polyu.hk escribió: Anyone help with this question please….? Really need some feedback to continue my work. Many thanks guys!!! Best Zeya On 24 Oct, 2014, at 12:22 am, Zeya Aung 115478...@connect.polyu.hk wrote: Hey guys I’m missing some data in my real case analysis. Please advise on the best approximation methods and assumptions. 1) Generator (min and max Q limit) - I’ve the power factor and capacity, and i suppose the max Q generation can be assumed using the p.f, but how about min Q? 2) Line transfer capacity - I’ve all the impedance, susceptance, and length, should i set 9900 in rateA of manpower format? Is this realistic? 3) Generator cost functions - for hydropower, coal power and natural gas turbines, how can i best approximate the cost functions? 4) I’ve the load profile (i.e. max load per month at transformers) but i do not have the generator data supplying this load. What can i do about this considering there are no accurate generation cost functions to run a optimal power flow and get a steady state solution? Many thanks. Best Zeya - Disclaimer: This message (including any attachments) contains confidential information intended for a specific individual and purpose. If you are not the intended recipient, you should delete this message and notify the sender and The Hong Kong Polytechnic University (the University) immediately. Any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited and may be unlawful. The University specifically denies any responsibility for the accuracy or quality of information obtained through University E-mail Facilities. Any views and opinions expressed are only those of the author(s) and do not necessarily represent those of the University and the University accepts no liability whatsoever for any losses or damages incurred or caused to any party as a result of the use of such information. - Disclaimer: This message (including any attachments) contains confidential information intended for a specific individual and purpose. If you are not the intended recipient, you should delete this message and notify the sender and The Hong Kong Polytechnic University (the University) immediately. Any disclosure, copying, or distribution of this message, or the taking of any action based on it, is strictly prohibited and may be unlawful. The University specifically denies any responsibility for the accuracy or quality of information obtained through University E-mail Facilities. Any views and opinions expressed are only those of
Re: PQ Capability HVDC Converter
Hi Christian, See Table B-5 in the User’s Manual http://www.pserc.cornell.edu/matpower/manual.pdf. I think the QMINF, QMAXF, QMINT, QMAXT are the parameters you are looking for, right? Ray On Nov 4, 2014, at 3:54 AM, Christian Orberger christian.orber...@outlook.com wrote: Hi Uriel, thank you for your answer. I saw in the user manual under point 7.5.3 DC Transmission lines that DC Lines are implemented with Dummy Generators. I would assume that these dummy Generators can be seen in general as Converters. So, I think I just have to put constraints on these dummy generators. But where are these constraints defined or in other words: are there already constraints at all? What do you think about my thoughts? Would you agree? From: uriel_sando...@ieee.org mailto:uriel_sando...@ieee.org Subject: Re: PQ Capability HVDC Converter Date: Mon, 3 Nov 2014 07:02:30 -0600 To: matpowe...@list.cornell.edu mailto:matpowe...@list.cornell.edu Hi Christian, As far as i know, matpower does not include FACTS devices (such HVDC), you will have to code it. Best regards, Uriel El 03/11/2014, a las 6:51, Christian Orberger christian.orber...@outlook.com mailto:christian.orber...@outlook.com escribió: Hello, I want to extend the P-Q constraints of an HVDC Converter in the OPF in Matpower. My question is, if there already are any constraints regarding these converters in the OPF and if yes, where I can find them in the programm? Or do I have to implement completely new constraints? Thank you for your help! Best regards, Christian
Re: Way to avoid the pretty-printing of results on the Command Window
Marco,
What you want to do is not currently possible simply by setting an option (and
I consider this a bug worth fixing). But this is the great thing about
open-source software, you can very trivially make a modification to suit your
needs.
In your case, an easy fix would be to make a copy of runpf.m under a different
name, and comment out the second call to printf() (line 357 in my current
version), and then call this function instead of runpf().
--
Ray Zimmerman
Senior Research Associate
B30 Warren Hall, Cornell University, Ithaca, NY 14853 USA
phone: (607) 255-9645
On Nov 3, 2014, at 10:29 AM, Simone Cochi simoneco...@gmail.com wrote:
I've never used it before but maybe the MP function printpf could fit
your needs.
2014-11-03 15:11 GMT+01:00 Marco Barbetta marco.barbetta1...@gmail.com:
Thank you for answers, but i'm looking for a way to avoid the
pretty-printing of results ONLY on command window, while i need to store the
results (pretty - printed) for each cycle in text (and .mat) files. I know
that results can be stored in the results struct, but i'd prefer another
copy in .txt files.
Is it possible?
Thanks,
Marco Barbetta
2014-11-03 14:59 GMT+01:00 Simone Cochi simoneco...@gmail.com:
mpopt=mpoption('verbose',0,'out.all',0)
2014-11-03 14:51 GMT+01:00 Marco Barbetta marco.barbetta1...@gmail.com:
Dear collegues,
i'm implementing a code on MatLab, using MATPOWER, and i have to do a
huge
number of for-cycles: at the end of every cycle, i have to print the
results
on two files (.txt and .mat) in automatic, through the command below:
results = runpf(mpc,mpopt,['Risultati_step_' num2str(k)
'.txt'],['Risultati_step_' num2str(k) '.mat']);
At every cycle, MATPOWER prints the results also in the Command Window.
I'm
finding a way to avoid the pretty-printing of results on the Command
Window,
in order to visualize properly some warnings and flags that i have
positioned in the code.
Can you help me? I'm searching in the Manual (appendix C - MATPOWER
options)
but i could not find the answer, yet.
Best regards,
Marco Barbetta
Re: What is the syntax used for fast decoupled load flow?
See the first example in section 2.3.4 in the User’s Manual http://www.pserc.cornell.edu/matpower/manual.pdf on Setting Options. Ray On Nov 3, 2014, at 10:32 AM, vivek rastogi vivekrastogi1...@gmail.com wrote: From Vivek Rastogi NIT Hamirpur Sent from my Nokia phone
Re: Way to avoid the pretty-printing of results on the Command Window
Thank you very much Dr. Zimmerman, i'll try this fix as soon as possible
and i'll inform you about the results.
Best regards,
Marco Barbetta
2014-11-04 17:28 GMT+01:00 Ray Zimmerman r...@cornell.edu:
Marco,
What you want to do is not currently possible simply by setting an option
(and I consider this a bug worth fixing). But this is the great thing about
open-source software, you can very trivially make a modification to suit
your needs.
In your case, an easy fix would be to make a copy of runpf.m under a
different name, and comment out the second call to printf() (line 357 in
my current version), and then call this function instead of runpf().
--
Ray Zimmerman
Senior Research Associate
B30 Warren Hall, Cornell University, Ithaca, NY 14853 USA
phone: (607) 255-9645
On Nov 3, 2014, at 10:29 AM, Simone Cochi simoneco...@gmail.com wrote:
I've never used it before but maybe the MP function printpf could fit
your needs.
2014-11-03 15:11 GMT+01:00 Marco Barbetta marco.barbetta1...@gmail.com:
Thank you for answers, but i'm looking for a way to avoid the
pretty-printing of results ONLY on command window, while i need to store
the
results (pretty - printed) for each cycle in text (and .mat) files. I know
that results can be stored in the results struct, but i'd prefer another
copy in .txt files.
Is it possible?
Thanks,
Marco Barbetta
2014-11-03 14:59 GMT+01:00 Simone Cochi simoneco...@gmail.com:
mpopt=mpoption('verbose',0,'out.all',0)
2014-11-03 14:51 GMT+01:00 Marco Barbetta marco.barbetta1...@gmail.com:
Dear collegues,
i'm implementing a code on MatLab, using MATPOWER, and i have to do a
huge
number of for-cycles: at the end of every cycle, i have to print the
results
on two files (.txt and .mat) in automatic, through the command below:
results = runpf(mpc,mpopt,['Risultati_step_' num2str(k)
'.txt'],['Risultati_step_' num2str(k) '.mat']);
At every cycle, MATPOWER prints the results also in the Command Window.
I'm
finding a way to avoid the pretty-printing of results on the Command
Window,
in order to visualize properly some warnings and flags that i have
positioned in the code.
Can you help me? I'm searching in the Manual (appendix C - MATPOWER
options)
but i could not find the answer, yet.
Best regards,
Marco Barbetta
Re: Convergence problem in runpf for contingency
Dear Jose L. Marin and Dr.Zimmerman, Thank you Mr.Jose L. Marin for your detailed explanations. I also thank Dr.Zimmerman for giving hint in using find_islands() function. Regards, Babulal On 31-10-2014 18:15, Jose Luis Marin wrote: Hello Babulal, I believe that the problem is that MATPOWER does not automatically remove islands when running a powerflow. Each of the three contingencies you list happen to isolate a bus, therefore the network needs to be reduced prior to the call to runpf (Ray -- please correct me if I'm wrong). You can use extract_islands() for this: mpc = loadcase(IEEE30_Conting9_11) mpc = version: '2' baseMVA: 100 bus: [30x13 double] gen: [6x25 double] branch: [41x13 double] mpc_reduced = extract_islands(mpc, 1) mpc_reduced = version: '2' baseMVA: 100 bus: [29x13 double] gen: [5x25 double] branch: [40x13 double] Running runpf() on this reduced case works OK for the contingencies you list. -- Jose L. Marin Gridquant España SL Grupo AIA On Fri, Oct 31, 2014 at 9:41 AM, ckbeee ckb...@tce.edu wrote: Dear Dr.Zimmerman, When I perform the power flow for the following contingency in case_ieee30.m system, MATPOWER experiences numerical instability. 1. Line number 13 (Connected between buses 9-11) 2. Line number 16 (Connected between buses 13-12) 3. Line number 34 (Connected between buses 25-26) It means no solution exist for these contingencies. It does not give results for OPF also. Thanks in advance. Regards, Babulal -- Assistant Professor Department of Electrical and Electronics Engineering Thiagarajar College of Engineering. Madurai-625 015. Tamilnadu. India. Mobile: +91 98439 17258 [1] ck_babu...@gmail.com -- This email was sent using TCEMail Service. Thiagarajar College of Engineering Madurai-625 015, India -- Assistant Professor Department of Electrical and Electronics Engineering Thiagarajar College of Engineering. Madurai-625 015. Tamilnadu. India. Mobile: +91 98439 17258 ck_babu...@gmail.com -- This email was sent using TCEMail Service. Thiagarajar College of Engineering Madurai-625 015, India Links: -- [1] tel:%2B91%2098439%2017258
