Refined ramp event characterisation for wind power ramp control using energy storage system

With the advantages of fast response and bidirectional charge/discharge, an energy storage system (ESS) plays a promising role in wind power ramp control. In this study, an optimisation model based on refined ramp event characterisation is proposed to achieve continuous wind power ramp control using ESS. Firstly, four kinds of ramp scenarios are characterised considering both the wind power ramp event prediction and the charge/discharge state of ESS. State of charge of ESS is managed within its limits during ramp control, based on the classified ramp scenarios. Secondly, for the classified ramp scenarios, an active adjustment strategy is proposed to decide the expected charging/discharging energy of ESS according to the conditions of wind power and ESS. Thus, an appropriate energy storage reserve can be determined for anticipated ramp events. Refined ramp event characterisation is able to achieve better control performance with higher satisfaction of ramp requirement, less wind energy curtailment as well as promising adaptability to different ramp event predictions, wind conditions and changes of ESS parameters. The effectiveness of the proposed method is verified through case studies with real-world data from a 100 MW wind farm in China.