Security constrained DC OPF considering generator responses

Considering generator responses after contingencies provides a more practical solution to security constrained direct current optimal power flow (DCOPF) problems. The major difficulty of solving such OPF includes the large number of contingencies and non-convexity of the generator response constraints. In the literature, mixed-integer linear programming (MILP) formulation relying on big-M technique has been applied to deal with the non-convexity of generator response constraints. In this paper, we further improve the solving speed by formulating generator response constraints via bilinear expressions and adopting Benders’ decomposition technique to decompose the problem into a master problem and multiple subproblems, with each subproblem associated with a contingency. Benders’ decomposition strategies were investigated in this research to seek an efficient decomposition approach. Through preserving bilinear expressions related to the base case power while relaxing the rest bilinear expressions via McCormick envelops, we designed an efficient Benders’ decomposition strategy. Case study results demonstrate the efficiency of the proposed formulation compared to the state-of-the-art formulations. © 2020 Elsevier B.V.