Mode-Shape Deformation of Power System DAEs by Time-Domain Integration Methods

This paper studies the numerical deformation that time-domain integration (TDI) methods introduce to the shape of the coupling between the dynamic modes and variables of power system models. To this aim, we employ a small-signal stability analysis (SSSA)-based framework where such mode-shape deformation is efficiently identified by comparing the modal participation factors (PFs) of the power system model with the PFs of the discrete-time system that is derived from the application of the TDI method. The proposed approach is illustrated for TDI methods commonly used in dynamic power system calculations.