Hi Thanks a lot for the input Ray .
Matpower is a great tool, thanks to all of you guys for developing it. Regards Nair On Tue, Jan 20, 2015 at 8:50 AM, Ray Zimmerman <[email protected]> wrote: > You do not *need* to multiply the generation, but if you don’t then all of > the additional generation, as you increase load, will come from the slack > generator. Scaling the other generators is simply a more uniform way to > handle the additional load. > > Lambda is the continuation parameter and is proportional to the power. > Lambda = 0 means you are at the base loading level and Lambda = 1 means you > are at the target loading level. See equations (5.3) and (5.4) in the User’s > Manual <http://www.pserc.cornell.edu/matpower/manual.pdf> for the details. > > Ray > > > On Jan 17, 2015, at 10:24 PM, arun s nair <[email protected]> wrote: > > Hi > > Thanks a lot of the input Shri, I am able to run the code now and now able > to get the nose power and voltage values. > > I used the below code. > > define_constants; > mpopt = mpoption('out.all',0,'verbose',2,'out.bus',1); > mpopt = mpoption(mpopt,'cpf.stop_at','nose','cpf.step',0.2); > mpopt = mpoption(mpopt,'cpf.plot.bus',4,'cpf.plot.level',2); > mpcb = loadcase('case39'); % load base case > mpct = mpcb; % set up target case with > mpct.gen(:,[PG QG]) = mpcb.gen(:,[PG QG])*2 > mpct.bus(:,[PD QG]) = mpcb.bus(:,[PD QG])*2 > results = runcpf(mpcb, mpct, mpopt); > realpower = results.bus(4,3) > vm = results.bus(4,8) > > I have a small doubt, In the example for plotting the PV curve, they are > both multiplying the load and generation by a factor. For plotting the > curve do we need to multiply the gen bus also? > > One more doubt, in the curve its V vs Lamda, is the lamda factor same as > power? > > Sorry if these are silly doubts, I am new to Matpower and the power area. > > Thanking in advance. > > Nair > > > > > On Fri, Jan 16, 2015 at 12:30 PM, Abhyankar, Shrirang G. < > [email protected]> wrote: > >> runcpf returns a MATPOWER case struct that has the loading/genration >> and the voltages at its last continuation step. By using the option >> 'cpf_stop_at_nose', the continuation power flow will stop when it is near >> the nose point. You can then extract the voltages and power from the >> MATPOWER case struct. >> >> For example, >> >> define_constants; >> mpopt = mpoption('out.all',0,'verbose',2); >> mpopt = mpoption('cpf.stop_at','nose','cpf.step',0.2); >> mpopt = mpoption(mpopt,'cpf.plot.level',2); >> mpcb = loadcase('case39'); % load base case >> mpct = mpcb; % set up target case with >> mpct.gen(:, [PG QG]) = mpcb.gen(:, [PG QG])*2.5 >> mpct.bus(:,[PD QG]) = mpcb.bus(:,[PD QG])*2.5 >> results = runcpf(mpcb, mpct, mpopt); >> >> Vm = results.bus(:,8); % Voltage magnitude at the nose point for all >> the buses. >> >> Other values can be extracted from the case struct by accessing the >> appropriate fields and their corresponding columns. The data format for the >> case struct is defined in caseformat.m. >> >> Shri >> >> >> >> From: arun s nair <[email protected]> >> Reply-To: MATPOWER discussion forum <[email protected]> >> Date: Fri, 16 Jan 2015 12:06:50 -0700 >> To: MATPOWER discussion forum <[email protected]> >> Subject: Re: Matpower- Continuation Power Flow >> >> Hi >> >> Thank you Abhyanker for your input, the example in the manual worked. >> >> I am really new to Matpower and I am learning it from scratch. My >> intention is to get the critical value of power and voltage values(Nose >> point of the PV curve) of a particular bus, Can anyone please tell me is >> it possible to get the values using Matpower using continuation power flow >> ? >> >> I am trying to modify the example code from the manual (I am working on >> IEEE 39 bus system) >> >> define_constants; >> mpopt = mpoption('out.all',0,'verbose',2); >> mpopt = mpoption('cpf.stop_at','nose','cpf.step',0.2); >> mpopt = mpoption(mpopt,'cpf.plot.level',2); >> mpcb = loadcase('case39'); % load base case >> mpct = mpcb; % set up target case with >> mpct.gen(:, [PG QG]) = mpcb.gen(:, [PG QG])*2.5 >> mpct.bus(:,[PD QG]) = mpcb.bus(:,[PD QG])*2.5 >> results = runcpf(mpcb, mpct, mpopt); >> results.cpf >> >> >> Thanking in advance >> >> Regards >> >> Nair >> >> >> On Thu, Jan 15, 2015 at 3:25 PM, Abhyankar, Shrirang G. < >> [email protected]> wrote: >> >>> Arun, >>> You have the same generation/load for both the base (mpcb) and target >>> (mpct) cases. What are you seeing is that runcpf is solving the base case >>> over and over again since there is zero power transfer. Use different >>> generation/load for mpcb and mpct and run the continuation power flow >>> again. See the MATPOWER User's Manual >>> <http://www.pserc.cornell.edu//matpower/manual.pdf> for a CPF example >>> on a test 9-bus case. >>> >>> Shri >>> >>> From: arun s nair <[email protected]> >>> Reply-To: MATPOWER discussion forum <[email protected]> >>> Date: Thu, 15 Jan 2015 13:02:57 -0700 >>> To: <[email protected]> >>> Subject: Matpower- Continuation Power Flow >>> >>> Hi All >>> >>> I am trying to use matpower to evaluate IEEE 39 bus system and I tried >>> to run an example code for runcpf (Continuation Power Flow) >>> >>> define_constants; >>> mpopt = mpoption('out.all',0,'verbose',2); >>> mpopt = mpoption('cpf.stop_at','nose','cpf.step',0.2); >>> mpopt = mpoption(mpopt,'cpf.plot.level',2); >>> mpcb = loadcase(t_case9_pfv2); % load base case >>> mpct = mpcb; % set up target case with >>> mpct.gen(:, [PG QG]) = mpcb.gen(:, [PG QG]) >>> mpct.bus(2,[PD]) = mpcb.bus(2, [PD]) >>> results = runcpf(mpcb, mpct, mpopt); >>> results.cpf >>> >>> The program is keep on running and is not converging. Can anybody >>> please help on this. >>> >>> If anyone can send me a running example for runcpf of matpower , it >>> will be of great help and if anybody has worked on IEEE 39 bus using >>> runcpf, please let me know >>> >>> >>> Thanking you all in advance. >>> >>> Regards >>> >>> Arun Nair >>> >>> >>> >> > >
