  The synchronized operation of power generators is the foundation of electric
power system stability and key to the prevention of undesired power outages and
blackouts. Here, we derive the condition that guarantees synchronization in
electric power systems with high levels of inverter-based generation when
subjected to small perturbations, and perform a parametric sensitivity to
understand synchronization with varied types of generators. Contrary to the
popular belief that achieving a stable synchronized state is tied chiefly to
system inertia, our results instead highlight the critical role of generator
damping in achieving this pivotal state. Additionally, we report the
feasibility of operating interconnected electric grids with a 100% power
contribution from renewable generation technologies with assured system
synchronization. The findings of this paper can set the basis for the
development of advanced control architectures and grid optimization methods and
has the potential to further pave the path towards the decarbonization of the
electric power sector.
