  The synchrony of electric power systems is important in order to maintain
stable electricity supply. Recently, the measure basin stability was introduced
to quantify a node's ability to recover its synchronization when perturbed. In
this work, we focus on how basin stability depends on the coupling strength
between nodes. We use the Chilean power grid as a case study. In general, basin
stability goes from zero to one as coupling strength increases. However, this
transition does not happen at the same value for different nodes. By
understanding the transition for individual nodes, we can further characterize
their role in the power-transmission dynamics. We find that nodes with an
exceptionally large transition window also have a low community consistency. In
other words, they are hard to classify to one community when applying a
community detection algorithm. This also gives an efficient way to identify
nodes with a long transition window (which is computationally time consuming).
Finally, to corroborate these results, we present a stylized example network
with prescribed community structures that captures the mentioned
characteristics of basin stability transition and recreates our observations.
