Hi Surabhi, It seems the problem is with your network, not with the power flow algorithm. *Technical interpretation:* For the generation and demand you are targeting; your network is N-1 contingency incompliant. *Mathematical interpretation:* Because of the above problem, power flow Jacobian is becoming singular. As we know, Jacobian needs to be inverted in every iteration. But inversion is failing because the matrix is singular.
You may correct the issue as below. Solution-1: Increase the number of Newton Iterations and try again. But I don’t think it will work. Solution-2: Rather than disconnecting the line, change its impedance to very large value. This should work, and it represents your outage condition. You will see almost no flow on the line after power flow converged. Solution-3: Take a different network. Solution-4: Fix your network first, and then analyze your scenario again. Best Regards, Dr JGunda Optimization Engineer Power Systems & Electricity Markets *GE Grid Solutions Denmark* LinkedIn: https://www.linkedin.com/in/jgunda/ Google Scholar: https://scholar.google.co.uk/citations?user=Zy1m33QAAAAJ&hl=en ResearchGate: https://www.researchgate.net/profile/Jagadeesh_Gunda On Wed, 9 Sep 2020 at 09:12, Surbhi Aggarwal <[email protected]> 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 >
