  The increasing frequency of extreme weather events has posed significant
risks to the operation of power grids. During long-duration extreme weather
events, microgrid formation (MF) is an essential solution to enhance the
resilience of the distribution systems by proactively partitioning the
distribution system into several microgrids to mitigate the impact of
contingencies. This paper proposes a distributionally robust dynamic microgrid
formation (DR-DMF) approach to fully consider the temporal characteristics of
line failure probability during long-duration extreme weather events like
typhoons. The boundaries of each microgrid are dynamically adjusted to enhance
the resilience of the system. Furthermore, the expected load shedding is
minimized by a distributionally robust optimization model considering the
uncertainty of line failure probability regarding the worst-case distribution
of contingencies. The effectiveness of the proposed model is verified by
numerical simulations on a modified IEEE 37-node system.
