N-k-e Survivable Power System Design

We consider the problem of designing (or augmenting) an electric power system such that it satisfies the N-k-e survivability criterion while minimizing total cost. The survivability criterion requires that at least (1-e) fraction of the total demand can still be met even if any k (or fewer) of the system components fail. We formulate this problem, taking into account both transmission and generation expansion planning, as a mixed-integer program. Two algorithms are designed and tested on modified instances from the IEEE-30-Bus and IEEE- 57-Bus systems.