Hierarchical Unit Commitment With Uncertain Wind Power Generation

A hierarchical unit commitment (HUC) model is presented with the objective of maintaining system security by scheduling reserves in power systems with high wind penetration. The reserves in the HUC model include generation reserve, ramping reserve, and transmission reserve. These three reserves are proposed to guarantee system security with uncertain wind power. Moreover, the simplifications for the transmission reserve are applied to reduce computational burden. The hierarchical scheduling strategy, which considers both conventional and emergency operations, divides the wind power output into two intervals based on confidence levels, and uses different scheduling strategies for different intervals of wind power output. Finally, case studies compare HUC with RUC and SUC, which shows the effectiveness in system safety enhancement and the effectiveness in practical systems of the proposed HUC model.