Probabilistic small-signal analysis case studies in detailed power system models with converter-interfaced generation

This paper investigates probabilistic small-signal analysis (PSSA) case studies in a power system permeated with converter-interfaced generation, represented with detailed modelling. The uncertainty introduced by the uptake of renewable energy sources necessitates the use of probabilistic methods in dynamic analysis. PSSA using the Monte Carlo approach can reveal the probability of small-signal instability or ensure small-signal robustness across the operating range, while offering insights into the potential multi-machine interactions that can occur in the system being studied. Therefore, case studies are performed in this paper which detail the impact of different heterogeneous generation mixtures (i.e., synchronous generators, and grid-following and grid-forming converters), and the operational timescales of the grid-forming converter controllers, on probabilistic small-signal dynamics and stability of the commonly utilised IEEE 9-bus system.