Chance-Constrained Unit Commitment with N-1 Security and Wind Uncertainty
For grid operators, this work provides a method to reliably and economically manage day-ahead unit commitment under wind uncertainty and N-1 security constraints.
Grid operators face challenges integrating wind energy due to its variability, risking overloads and cascading events. The paper presents a chance-constrained unit commitment model with N-1 security that limits failure probability, solved via a modified Benders decomposition, achieving scalable and cost-effective solutions on IEEE test systems.
As renewable wind energy penetration rates continue to increase, one of the major challenges facing grid operators is the question of how to control transmission grids in a reliable and a cost-efficient manner. The stochastic nature of wind forces an alteration of traditional methods for solving day-ahead and look-ahead unit commitment and dispatch. In particular, the variability of wind generation increases the risk of unexpected overloads and cascading events. To address these questions, we present an N-1 Security and Chance-Constrained Unit Commitment (SCCUC) that includes models of generation reserves that respond to wind fluctuations and component outages. We formulate the SCCUC as a mixed-integer, second-order cone problem that limits the probability of failure. We develop a modified Benders decomposition algorithm to solve the problem to optimality and present detailed case studies on the IEEE RTS-96 three-area and the IEEE 300 NESTA test systems. The case studies assess the economic impacts of contingencies and various degrees of wind power penetration and demonstrate the effectiveness and scalability of the algorithm.