This paper proposes a strategy to identify the parameter data for representing an 11-bus system for execution as a case in the MATPOWER software and discusses the ill-conditioned problem associated with it. The referred power system model is largely studied for evaluating iterative nonlinear method performances considering ill-conditioned systems. The case data are generated by converting the entry values of the system admittance matrix (matrix Ybus) into a hypothetical network. The parameters of this network are identified in the form of longitudinal and transversal admittance in order to preserve the same precision of the given original matrix Ybus. It is demonstrated that the power flow problem (PFP) solution diverges for a flat start guess when the standard Newton-Raphson (NR) method is used. However, by considering a very small reduction on the loading level the PFP converges. Even for this situation, the problem has elevated condition numbers along the iterations of the NR. Therefore, the paper focuses on the ill-conditioned study of the system, besides presenting case data which is appropriated to run in the MATLAB’s format free code, MATPOWER.