Check if any buses are actually isolated but their bustype hasn't been set to isolated (4). On Jan 5, 2013, at 6:33 AM, Hwachang SONG wrote:
> Dear Prof. Zimmerman, > > Recently, I applied matpower power flow for a converted real power system > with 2018 buses. > But the simulation does not converge, with the following message: > > Warning: Matrix is singular to working precision. > > In newtonpf at 109 > In runpf at 220 > > And the bus voltages and angles are all NaN. > > Is there any method to fix this problem? > > Thanks. > > Hwachang Song > > > > > Hwachang SONG (Ph.D.) > Associate Professor > Dept. of Electrical and Information Engineering > Seoul Nat'l Univ. of Science and Technology (SeoulTech) > Republic of Korea > Phone: +82-2-970-6403 > Mobile: +82-10-7322-4605 > Fax: +82-2-978-2754 > >
