  The problem of partitioning a power grid into a set of islands can be a
solution to restore power dispatchment in sections of a grid affected by an
extreme failure. Current solutions to this problem usually involve finding the
partition of the grid into islands that minimizes the sum of their absolute
power imbalances. This combinatorial problem is often solved through heuristic
offline methods. In this paper, we propose instead a distributed online
algorithm through which nodes can migrate among islands, self-organizing the
network into a suitable partition. We prove that, under a set of appropriate
assumptions, the proposed solution yields a partition whose absolute power
imbalance falls within a given bound of the optimal solution. We validate our
analytical results by testing our partitioning strategy on the IEEE 118 and 300
benchmark problems.
