Hi, It's the file or casefile or M-file/MAT-file on which you are performing opf operations for analysis. e.g. runopf(case9) here *case9 *is the file he asked for. Thanks Mirish
On Wed, Sep 16, 2020 at 6:43 AM Surbhi Aggarwal <surbhiaggarwa...@gmail.com> wrote: > Which file do I need to send you? > please specify it. > > Regards > Surbhi Aggarwal > > > On Tue, Sep 15, 2020 at 7:03 PM Ray Daniel Zimmerman <r...@cornell.edu> > wrote: > >> Looks like the Jacobian is singular. Feel free to send me the case >> (off-list) and I’ll have a look. >> >> Ray >> >> >> On Sep 14, 2020, at 11:35 PM, Surbhi Aggarwal <surbhiaggarwa...@gmail.com> >> wrote: >> >> Even after doing everything, this error prompts out. >> Please help me out with this issue. >> >> Warning: Matrix is singular to working precision. >> > In mplinsolve (line 75) >> In newtonpf (line 110) >> In runpf (line 260) >> >> >> Regards >> Surbhi Aggarwal >> >> >> On Mon, Sep 14, 2020 at 7:31 PM Ray Daniel Zimmerman <r...@cornell.edu> >> wrote: >> >>> You would have to confirm the cause of the non-convergence before >>> drawing any conclusions. You may find FAQ #5 >>> <https://matpower.org/doc/faq/#pfconvergence> helpful. >>> >>> Ray >>> >>> On Sep 12, 2020, at 6:43 AM, Surbhi Aggarwal <surbhiaggarwa...@gmail.com> >>> wrote: >>> >>> Hello >>> If the system does not converge within 10 iterations, can we say that it >>> is one of the most severely affected lines in contingency studies? >>> Or any other explanation for this non-convergence? >>> Regards >>> Surbhi Aggarwal >>> >>> >>> On Sat, Sep 12, 2020 at 10:40 AM Surbhi Aggarwal < >>> surbhiaggarwa...@gmail.com> wrote: >>> >>>> Hello >>>> Thank you all for your help and I'll definitely look out for the >>>> solutions. >>>> Thank you so much >>>> Regards >>>> Surbhi Aggarwal >>>> >>>> >>>> On Fri, Sep 11, 2020 at 7:16 PM Ray Daniel Zimmerman <r...@cornell.edu> >>>> wrote: >>>> >>>>> Hi Surbhi, >>>>> >>>>> It looks like you were using the default Newton power flow. To >>>>> increase the number of iterations, you can increase the pf.nr.max_it >>>>> option. However, this is rarely necessary. If the Newton method is going >>>>> to >>>>> converge, it usually does so in less than the default 10 iterations. If it >>>>> is not converging within 10 iterations, it is likely that the problem has >>>>> no solution or that you need a better starting point. >>>>> >>>>> Ray >>>>> >>>>> >>>>> On Sep 11, 2020, at 5:48 AM, Mirish Thakur <mirishtha...@gmail.com> >>>>> wrote: >>>>> >>>>> Hi Surbhi, >>>>> >>>>> First of all why do you want to increase the number of steps/ >>>>> iterations in the calculation? Is there any specific need? Actually the >>>>> number of iterations depends on the power flow optimization tolerance. >>>>> Maybe you can focus on the mpoption function and read it carefully. You >>>>> can >>>>> update something like here: >>>>> mpopt = mpoption('pf.alg', 'FDXB', 'pf.tol', 1e-4) >>>>> I'm not 100 % sure about it but it may help you. Thanks. >>>>> >>>>> Kind regards >>>>> Mirish >>>>> >>>>> On Fri, Sep 11, 2020 at 8:41 AM Surbhi Aggarwal < >>>>> surbhiaggarwa...@gmail.com> wrote: >>>>> >>>>>> Hello Everyone, >>>>>> I tried your suggestions and it somehow helped me. >>>>>> Now my doubt is " If I want to increase my number of iterations, what >>>>>> steps I have to do"? >>>>>> Please help me out >>>>>> Regards >>>>>> Surbhi Aggarwal >>>>>> >>>>>> >>>>>> On Wed, Sep 9, 2020 at 7:50 PM Ray Daniel Zimmerman <r...@cornell.edu> >>>>>> wrote: >>>>>> >>>>>>> I also suspect that the network becomes disconnected by removing >>>>>>> certain lines. You can check the connectivity using case_info() >>>>>>> <https://matpower.org/docs/ref/matpower7.0/lib/case_info.html> or >>>>>>> find_islands() >>>>>>> <https://matpower.org/docs/ref/matpower7.0/lib/find_islands.html>. >>>>>>> If there are islands, then each island needs to have its own reference >>>>>>> bus, >>>>>>> and the local generation needs to be able to meet the local load in each >>>>>>> island. >>>>>>> >>>>>>> Ray >>>>>>> >>>>>>> >>>>>>> On Sep 9, 2020, at 4:57 AM, Mirish Thakur <mirishtha...@gmail.com> >>>>>>> wrote: >>>>>>> >>>>>>> Hi Surbhi, >>>>>>> >>>>>>> Could you please check the continuity of the system before running >>>>>>> opf? I mean to say if you run opf for (n-1) criteria the system should >>>>>>> be >>>>>>> still well connected. There shouldn't be any island within the system >>>>>>> itself. Perhaps you can test your model by removing any one parallel >>>>>>> line >>>>>>> (which you can observe later for analysis) and run the model under (n-1) >>>>>>> criteria. This could be the easiest way to test the model. Thank you. >>>>>>> >>>>>>> Kind regards >>>>>>> Mirish >>>>>>> >>>>>>> >>>>>>> On Wed, Sep 9, 2020 at 9:11 AM Surbhi Aggarwal < >>>>>>> surbhiaggarwa...@gmail.com> wrote: >>>>>>> >>>>>>>> Dear All, >>>>>>>> I am working on optimal power flow to find the contingency (N-1) >>>>>>>> situation of the system. For some of the line outage, certain output >>>>>>>> pops >>>>>>>> out >>>>>>>> >>>>>>>> MATPOWER Version 7.0, 20-Jun-2019 -- AC Power Flow (Newton) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> Warning: Matrix is singular to working precision. >>>>>>>> > In mplinsolve (line 75) >>>>>>>> In newtonpf (line 110) >>>>>>>> In runpf (line 260) >>>>>>>> >>>>>>>> Newton's method power flow (power balance, polar) did not converge >>>>>>>> in 10 iterations. >>>>>>>> >>>>>>>> >>>>> Did NOT converge (7.38 seconds) <<<<< >>>>>>>> >>>>>>>> What to do to correct this error. It would be of great help. >>>>>>>> Regards >>>>>>>> Surbhi Aggarwal >>>>>>>> >>>>>>> >>>>>>> >>>>> >>> >>
