Contingency-constrained robust transmission expansion planning under uncertainty

This paper studies the problem of robust transmission expansion planning (TEP) considering the N-k contingency and the uncertainty of load demand and renewable energy source (RES) generation. The expansion plan needs to meet constraints under the normal state and N-k contingency. Under the normal state, the problem to determine the worst-case loss-of-load and RES spillage is reformulated as a mixed integer linear programming (MILP) problem by application of dual theory. Under the N-k contingency, the problem to determine the worst-case loss-of-load is also reformulated as a MILP problem. The whole TEP problem is solved by the technique of Benders decomposition (BD). The expansion plan obtained by the proposed approach in this paper can accommodate all possible realizations of uncertain parameters defined by the uncertainty budget under both normal state and contingencies. Case studies are carried out on the revised IEEE 24-bus test system and revised IEEE RTS-96. Results show the optimal expansion plan is greatly affected by the uncertainty budget and N-k contingency.