Ismael, Power flow with loads modeled as “constant power” faces convergence issue when the voltages are low. A common trick is to convert constant power loads to constant impedance loads for low voltages. In MATPOWER, you can convert all the loads to constant impedance using the options 'exp.sys_wide_zip_loads.pw' (real power) and 'exp.sys_wide_zip_loads.qw'. Here, pw and qw are fractions of constant power, constant current, and constant impedance load composition. For a constant impedance only load the fractions should be [0,0,1].
Shri From: <bounce-123652900-83373...@list.cornell.edu> on behalf of Ismael K Abdulrahman <ikabdulra...@students.tntech.edu> Reply-To: MATPOWER discussion forum <matpowe...@list.cornell.edu> Date: Saturday, June 1, 2019 at 1:17 AM To: "matpower-l@cornell.edu" <matpower-l@cornell.edu> Subject: Question about power flow for a system with faulted bus Dear Matpower community, I am a Ph.D. student working in power system dynamic analysis. I use Matpower for computing the initial values of the system variables. I want to find the initial values of the algebraic variables (voltage magnitude, voltage angle, generator current phasors...) at the time of disturbance. The disturbance is a three phase fault at one bus in the system, usually a load or zero-injection bus. I tried to consider the faulted bus as a generator with zero power and zero voltage, but the problem cannot be solved. I was wondering if there is any way to get around this problem? I greatly appreciate your help. Thanks in advance Ismael
