Constraint reduction method for security-constrained unit commitment based on an auxiliary optimization problem

As the key part of formulating a generation schedule, the Security-Constrained Unit Commitment (SCUC) problem is of vital importance in the optimizated operation of a power system. The SCUC problem has a large number of constraints and is thereby difficult to solve. We propose a constraint reduction method based on an auxiliary optimization problem. First, the auxiliary optimization problem related to a specific post-contingency security constraint is introduced, so that a sufficient and necessary condition for identifying redundant constraints can be established. Then, three acceleration methods for the identification process are introduced, including relaxing the auxiliary optimization problem, proposing a feasible criterion for pre-classification of post-contingency security constraints, and introducing multithread parallel computing. Finally, the effectiveness and correctness of the proposed method are verified on the simulation of IEEE118 test system. © 2021 Power System Protection and Control Press.