Transmission-constrained unit commitment based on Benders decomposition

An efficient algorithm based an Benders decomposition is proposed for dealing with the transmission-constrained unit commitment problem. Using Benders decomposition, the formulation of the unit commitment with transmission constraints is decomposed into a master problem and a subproblem. The master problem solves unit commitment without transmission constraints by augmented Lagrangian relaxation and the subproblem minimizes violations of transmission constraints by adjusting unit generation and phase shifter controls and testing the feasibility of the unit commitment schedule. In the case of infeasibility in transmission flows, a proper constraint (Benders cut) is introduced for unit commitment rescheduling based on violations in the subproblem. The iterative process between the master problem and the subproblem provides a minimum production cost solution for generation scheduling while satisfying transmission constraints. A modified IEEE-30 bus system is presented to demonstrate the efficiency of the method. (C) 1998 Published by Elsevier Science Ltd. All rights reserved.