Re: How to find max-load ability for each bus of power system
Thank you for your informative answers Abhyankar. One more thing, when I use *voltage_dev= max(absV') - min(absV') *to calculate the voltage deviation of each buses, I should set the cpf option to NOSE and not FULL. Is that also correct? On Thu, Nov 30, 2017 at 6:49 PM, Abhyankar, Shrirang G. wrote: > > > > > > > *From: * on behalf of > Electric > *Reply-To: *MATPOWER discussion forum > *Date: *Thursday, November 30, 2017 at 2:42 AM > *To: *MATPOWER discussion forum > *Subject: *Re: How to find max-load ability for each bus of power system > > > > Thank you for your hint Ray, > > I two questions about CPF, would be glad if someone reply. > >1. What is the specifics of the bus that CPF plots itself? Does it >means the voltage at that bus has been violated more than the others? > > > > When the option cpf.plot.level is set to greater than 0, CPF plots the bus > voltage magnitude for a given bus if the bus number is provided via the > option cpf.plot.bus. If this option is not used then it plots the voltage > magnitude for the bus (type PQ) with the largest transfer. > > > > 2) I calculate the voltage violation as follows: > > absV=abs(res.cpf.V); % nb* nitr > last_itr=size(absV,2); > voltage_dev= max(absV') - min(absV'); % voltage violation > figure(2) > bar ( voltage_dev) > > > > Is this correct? > > Looks fine to me for what you are trying to do. > > > > the curve that cpf plots is not always the same as the index of the bus > corresponding to max(voltage_dev) > > > > See my above point on which bus CPF selects for plotting. > > > > Thanks. > > > > > > On Tue, Nov 28, 2017 at 5:43 PM, Ray Zimmerman wrote: > > You may also want to consider the code in extras/maxloadlim which uses an > OPF to find the maximum loadability. You can find the manual for this code > on GitHub here > <https://github.com/MATPOWER/matpower-extras/blob/master/maxloadlim/manual/maxloadlim_manual.pdf> > . > > > >Ray > > > > > > On Nov 28, 2017, at 5:45 AM, Electric > wrote: > > > > Thank you for your informative answer. If I only increase the load at a > single bus, *i*, in the target case, does Max lambda indicates > vulnerability 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. > wrote: > > 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 the > base-case solution and lambda = 1 at the targetcase. Lambda can go beyond > or less than 1 depending on where the system collapses (maximum loadability > limit). > > > > From your question, it seems like you want to increase the load at a > single bus. For this, you merely need to modify the load for the given bus > in the targetcase data and run the CPF. > > > > Shri > > *From: * on behalf of > Electric > *Reply-To: *MATPOWER discussion forum > *Date: *Monday, November 27, 2017 at 4:23 AM > *To: *MATPOWER discussion forum > *Subject: *Fwd: How to find max-load ability for each bus of power system > > > > > > I am interested to find the max load-ability at each bus in order to find > the most critical buses in a power system in aspect of voltage stability. > How is it doable? > > I thought of cpf, but it merely returns the max lambda which is an index > for whole system. > > > > > > > > >
Re: How to find max-load ability for each bus of power system
From: on behalf of Electric Reply-To: MATPOWER discussion forum Date: Thursday, November 30, 2017 at 2:42 AM To: MATPOWER discussion forum Subject: Re: How to find max-load ability for each bus of power system Thank you for your hint Ray, I two questions about CPF, would be glad if someone reply. 1. What is the specifics of the bus that CPF plots itself? Does it means the voltage at that bus has been violated more than the others? When the option cpf.plot.level is set to greater than 0, CPF plots the bus voltage magnitude for a given bus if the bus number is provided via the option cpf.plot.bus. If this option is not used then it plots the voltage magnitude for the bus (type PQ) with the largest transfer. 2) I calculate the voltage violation as follows: absV=abs(res.cpf.V); % nb* nitr last_itr=size(absV,2); voltage_dev= max(absV') - min(absV'); % voltage violation figure(2) bar ( voltage_dev) Is this correct? Looks fine to me for what you are trying to do. the curve that cpf plots is not always the same as the index of the bus corresponding to max(voltage_dev) See my above point on which bus CPF selects for plotting. Thanks. On Tue, Nov 28, 2017 at 5:43 PM, Ray Zimmerman mailto:r...@cornell.edu>> wrote: You may also want to consider the code in extras/maxloadlim which uses an OPF to find the maximum loadability. You can find the manual for this code on GitHub here<https://github.com/MATPOWER/matpower-extras/blob/master/maxloadlim/manual/maxloadlim_manual.pdf>. Ray On Nov 28, 2017, at 5:45 AM, Electric mailto:electricaltranslat...@gmail.com>> wrote: Thank you for your informative answer. If I only increase the load at a single bus, i, in the target case, does Max lambda indicates vulnerability 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 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 the base-case solution and lambda = 1 at the targetcase. Lambda can go beyond or less than 1 depending on where the system collapses (maximum loadability limit). From your question, it seems like you want to increase the load at a single bus. For this, you merely need to modify the load for the given bus in the targetcase data and run the CPF. Shri From: mailto:bounce-122078874-73493...@list.cornell.edu>> on behalf of Electric mailto:electricaltranslat...@gmail.com>> Reply-To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Date: Monday, November 27, 2017 at 4:23 AM To: MATPOWER discussion forum mailto:matpowe...@list.cornell.edu>> Subject: Fwd: How to find max-load ability for each bus of power system I am interested to find the max load-ability at each bus in order to find the most critical buses in a power system in aspect of voltage stability. How is it doable? I thought of cpf, but it merely returns the max lambda which is an index for whole system.
Re: How to find max-load ability for each bus of power system
Thank you for your hint Ray, I two questions about CPF, would be glad if someone reply. 1) What is the specifics of the bus that CPF plots itself? Does it means the voltage at that bus has been violated more than the others? 2) I calculate the voltage violation as follows: absV=abs(res.cpf.V); % nb* nitr last_itr=size(absV,2); voltage_dev= max(absV') - min(absV'); % voltage violation figure(2) bar ( voltage_dev) Is this correct? the curve that cpf plots is not always the same as the index of the bus corresponding to max(voltage_dev) Thanks. On Tue, Nov 28, 2017 at 5:43 PM, Ray Zimmerman wrote: > You may also want to consider the code in extras/maxloadlim which uses an > OPF to find the maximum loadability. You can find the manual for this code > on GitHub here > <https://github.com/MATPOWER/matpower-extras/blob/master/maxloadlim/manual/maxloadlim_manual.pdf> > . > >Ray > > > On Nov 28, 2017, at 5:45 AM, Electric > wrote: > > Thank you for your informative answer. If I only increase the load at a > single bus, *i*, in the target case, does Max lambda indicates > vulnerability 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. > wrote: > >> 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 the >> base-case solution and lambda = 1 at the targetcase. Lambda can go beyond >> or less than 1 depending on where the system collapses (maximum loadability >> limit). >> >> >> >> From your question, it seems like you want to increase the load at a >> single bus. For this, you merely need to modify the load for the given bus >> in the targetcase data and run the CPF. >> >> >> >> Shri >> >> *From: * on behalf of >> Electric >> *Reply-To: *MATPOWER discussion forum >> *Date: *Monday, November 27, 2017 at 4:23 AM >> *To: *MATPOWER discussion forum >> *Subject: *Fwd: How to find max-load ability for each bus of power system >> >> >> >> >> >> I am interested to find the max load-ability at each bus in order to find >> the most critical buses in a power system in aspect of voltage stability. >> How is it doable? >> >> I thought of cpf, but it merely returns the max lambda which is an index >> for whole system. >> >> >> > > >
Re: How to find max-load ability for each bus of power system
You may also want to consider the code in extras/maxloadlim which uses an OPF to find the maximum loadability. You can find the manual for this code on GitHub here <https://github.com/MATPOWER/matpower-extras/blob/master/maxloadlim/manual/maxloadlim_manual.pdf>. Ray > On Nov 28, 2017, at 5:45 AM, Electric wrote: > > Thank you for your informative answer. If I only increase the load at a > single bus, i, in the target case, does Max lambda indicates vulnerability 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 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 the base-case > solution and lambda = 1 at the targetcase. Lambda can go beyond or less than > 1 depending on where the system collapses (maximum loadability limit). > > > > From your question, it seems like you want to increase the load at a single > bus. For this, you merely need to modify the load for the given bus in the > targetcase data and run the CPF. > > > > Shri > > From: <mailto:bounce-122078874-73493...@list.cornell.edu>> on behalf of Electric > mailto:electricaltranslat...@gmail.com>> > Reply-To: MATPOWER discussion forum <mailto:matpowe...@list.cornell.edu>> > Date: Monday, November 27, 2017 at 4:23 AM > To: MATPOWER discussion forum <mailto:matpowe...@list.cornell.edu>> > Subject: Fwd: How to find max-load ability for each bus of power system > > > > > > I am interested to find the max load-ability at each bus in order to find the > most critical buses in a power system in aspect of voltage stability. How is > it doable? > > I thought of cpf, but it merely returns the max lambda which is an index for > whole system. > > > >
Re: How to find max-load ability for each bus of power system
Thank you for your informative answer. If I only increase the load at a single bus, *i*, in the target case, does Max lambda indicates vulnerability 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. wrote: > 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 the > base-case solution and lambda = 1 at the targetcase. Lambda can go beyond > or less than 1 depending on where the system collapses (maximum loadability > limit). > > > > From your question, it seems like you want to increase the load at a > single bus. For this, you merely need to modify the load for the given bus > in the targetcase data and run the CPF. > > > > Shri > > *From: * on behalf of > Electric > *Reply-To: *MATPOWER discussion forum > *Date: *Monday, November 27, 2017 at 4:23 AM > *To: *MATPOWER discussion forum > *Subject: *Fwd: How to find max-load ability for each bus of power system > > > > > > I am interested to find the max load-ability at each bus in order to find > the most critical buses in a power system in aspect of voltage stability. > How is it doable? > > I thought of cpf, but it merely returns the max lambda which is an index > for whole system. > > >
Re: How to find max-load ability for each bus of power system
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 the base-case solution and lambda = 1 at the targetcase. Lambda can go beyond or less than 1 depending on where the system collapses (maximum loadability limit). From your question, it seems like you want to increase the load at a single bus. For this, you merely need to modify the load for the given bus in the targetcase data and run the CPF. Shri From: on behalf of Electric Reply-To: MATPOWER discussion forum Date: Monday, November 27, 2017 at 4:23 AM To: MATPOWER discussion forum Subject: Fwd: How to find max-load ability for each bus of power system I am interested to find the max load-ability at each bus in order to find the most critical buses in a power system in aspect of voltage stability. How is it doable? I thought of cpf, but it merely returns the max lambda which is an index for whole system.
Re: How to find max-load ability for each bus of power system
I will do, thanks. On Mon, Nov 27, 2017 at 10:03 PM, Mahbubur R wrote: > Hello, > Of course it is doable. And I think you are talking about the most > critical lines in a system. There are a number of line voltage stability > indexing methods available to do that - LQP, FVSI, LCPI etc. > > You can email me personally for more details. > > > Thanks > > On Mon, Nov 27, 2017 at 5:19 AM, Electric > wrote: > >> I am interested to find the max load-ability at each bus in order to find >> the most critical buses in a power system in aspect of voltage stability. >> How is it doable? >> I thought of cpf, but it merely returns the max lambda which is an index >> for whole system. >> > >
Re: How to find max-load ability for each bus of power system
Hello, Of course it is doable. And I think you are talking about the most critical lines in a system. There are a number of line voltage stability indexing methods available to do that - LQP, FVSI, LCPI etc. You can email me personally for more details. Thanks On Mon, Nov 27, 2017 at 5:19 AM, Electric wrote: > I am interested to find the max load-ability at each bus in order to find > the most critical buses in a power system in aspect of voltage stability. > How is it doable? > I thought of cpf, but it merely returns the max lambda which is an index > for whole system. >
Re: Fwd: How to find max-load ability for each bus of power system
Hi, If the CPF simultaneously increases the load at all load buses, then the lambda is applicable to each load individually. Although the lambda is scaled in MATPOWER. I hope it helps On Nov 27, 2017 11:23 AM, "Electric" wrote: I am interested to find the max load-ability at each bus in order to find the most critical buses in a power system in aspect of voltage stability. How is it doable? I thought of cpf, but it merely returns the max lambda which is an index for whole system.
Fwd: How to find max-load ability for each bus of power system
I am interested to find the max load-ability at each bus in order to find the most critical buses in a power system in aspect of voltage stability. How is it doable? I thought of cpf, but it merely returns the max lambda which is an index for whole system.
How to find max-load ability for each bus of power system
I am interested to find the max load-ability at each bus in order to find the most critical buses in a power system in aspect of voltage stability. How is it doable? I thought of cpf, but it merely returns the max lambda which is an index for whole system.
