Braess's paradox in oscillator networks, desynchronization and power outage

Robust synchronization is essential to ensure the stable operation many complex networked systems such as electric power grids. Increasing demands and more strongly distributing power sources raise the question where to add new connection lines to the already existing grid. Here we how the addition of individual links impacts the emergence of synchrony oscillator networks that model power grids on coarse scales. We reveal adding new links may not only promote but also destroy synchrony and this counter-intuitive phenomenon to Braess’s paradox known for traffic . We analytically uncover its underlying mechanism in an elementary example, trace its origin to geometric frustration in phase oscillators, and that it generically occurs across a wide range of systems. As an important , upgrading the grid requires particular care when adding new because some may destabilize the synchronization of the grid—and induce power outages.