A comprehensive tool for evaluation of critical electromechanical oscillation modes in very large power systems with optimal location and tuning of PSS

This paper addresses the presentation of a comprehensive tool for the analysis of electromechanical oscillations, through a complete or selective method, and the optimisation of the PSSs tuning to damp possible critical modes. The single components of the tool are presented separately and finally the interaction logic for the solution of the problem is presented. The tool is fully integrated in a niulti purpose commercial dynamic simulator and it has been tested on small and large networks with appreciable results. The computational time saving derived from the using of the Arnoldi modified method for the selective analysis is pointed out. An innovative approach for the optimal tuning of PSS devices is achieved taking in consideration a multi-machines, multi- scenarios system. An extract of the results so far achieved is presented.