摘要

This paper studies day-ahead unit commitment in wind-coal intensive power systems. Due to their long start up time, high start up cost, and high minimum stable output, coal-fired generators do not provide a favorable environment for accommodating variable wind generation. The reduced efficiencies resulting from the coal-fired generation side as measured in increased fuel consumption and CO2 emissions can greatly undermine the wind power benefits to the system if wind generation and coal-fired generation are not properly coordinated. Special attention in the study is given to the wind power benefits to the system in fuel savings and in reduction of CO2 emissions. Based on the wind power forecast, the stochastic nature of wind power is treated in two parts, i.e., wind power variability and wind power uncertainty. Unit commitment is studied using wind power variability and uncertainty separately in different wind power dispatch modes and using respectively different spinning reserve procurement strategies. System performance indices are then applied to determine the optimal wind power dispatch mode and optimal spinning reserve procurement strategy to capture optimal wind power benefits for the system. A simulation system characterized by typical wind-coal features is constructed to model and to conduct the studies. The results show that taking wind power curtailment as a control option and using wind as a reserve provider improve the wind power benefits to the system.