A Multi-level Two-stage Optimal Dispatch Model for Wind-storage Hybrid System

Energy storage contributes to facilitating wind power penetration as well as compensating grid-connected power fluctuation. Wind farms can improve overall on-grid revenues by taking full advantage of the characteristics of flexibility and rapidity of energy storage. This paper proposes a multi-level and multi-time scale optimal dispatch model for a wind-storage hybrid system. Firstly, the power grid provides the upper and lower on-grid power bounds of wind generation according to constraints of secure and stable power flow operation. Secondly, the wind-storage hybrid system makes power output through a two-stage model. In the day-ahead stage, the generation plan is optimized within the specified range considering short-term wind power forecasting and state of charge (SoC) characteristics of energy storage device. In the intra-day stage, ultra-short-term wind power forecast is introduced to rolling optimize generation schedule in 15-min interval. A modified IEEE 30-bus system is utilized to verify the effectiveness of the model.