Bug report: case14 converted from Matpower does not converge

[jinningwang]

Hi,

I converted the Matpower case14 in pandapower, but the power flow does not converge:

ssp_mp = pp.converter.from_mpc('case14.mat',
                               f_hz=60,
                               casename_mpc_file='mpc',
                               validate_conversion=True,
                               )

and the output is:

The shape of given ppc data indicates missing pypower powerflow results.
The pandapower powerflow does not converge.
Validation failed.

The detailed process is:

1. Matpower .mat file is generated using Matlab R2021a and Matpower 7.1 by command mpc = loadcase('case14'), saving the dict file 'mpc' as 'case14.mat'.
2. Using pandapower 2.7.0 to convert it.

Regards,
Jinning

[jinningwang]

The error is caused by the mpc file from Matpower defining bus(:, BASE_KV) as 0.
Modifying the bus voltage as a positive value will solve it.