Effect of variation in modelling of generator saturation on electromechanical modes

Several industrial-grade power system simulation tools are commercially available in the market. They are expensive to acquire and time-consuming to learn. As a result, very few institutions (utilities, academic/research organizations) can afford to use more than one power system simulation tool. The simulation tools differ in their components modelling. Different simulation tools can give different results for the same system model. Understanding the reasons for the discrepancies in the results is not a trivial task. In this paper, we investigate the effect of variations in modelling generator saturation. We carried out an eigenvalue analysis of a single machine infinite bus (SMIB) system using PSS/E, PowerFactory, EUROSTAG, SSAT, and MatNetEig. The simulation results show that the effect of saturation on the local modes is erratic and there is a need for further research on saturation representation in power system stability simulation tools.