用于提高风电场可调度性的储能系统预测控制策略

Smoothing and Dispatching the Output of Wind/Battery Energy Storage Hybrid System via Model Prediction Control

大规模储能的应用提高了风电场/群的可调度性,降低了大规模风电并网给电网带来的运行风险。为了充分利用储能系统柔性可控能力来提高风电场的可调度性,文中提出了基于模型预测控制(model prediction control,MPC)风/储集成发电系统滚动调控策略。该策略首先根据风功率预测结果制定风/储集成发电系统期望输出,即调度指令,进而通过滚动优化,在满足储能系统荷电状态、充放电深度等约束的前提下,计算得到下一调度周期内储能系统的控制指令,以保证风/储集成发电系统中风功率与储能系统有功的合成功率输出在最大程度上跟踪调度指令。以东北某风电场实际有功输出数据为基础,计算分析了在配置不同容量储能系统时该方法的控制效果,结果表明利用该方法对储能系统进行控制能够有效的提高风电场的可调度性,在跟踪调度指令的同时保证了集成发电系统合成输出功率的平滑性。

The application of large-scale energy storage makes wind farms more dispatchable, which lowers operating risks of the grid from interconnected large scale wind farms. In order to make full use of flexibility and controllability of energy storage to improve the schedulability of wind farms,we put forward a rolling and dispatching control strategy with a BESS based on model predictive control （MPC）. The proposed control scheme firstly plans expected output, i.e. dispatching order of wind/battery energy storage hybrid system based on the predicted output of the wind farm, then calculates the order in the predictive horizon with the receding horizon optimization and the limitations of energy storage such as state of charge and depth of charge/discharge to maintain the combination of active output of the wind farm and the BESS to track dispatching order at the extreme. Moreover, we analyze the effectiveness of the proposed strategy with different sizes of capacity of the BESS based on the actual output of a certain wind farm in the northeast of China. The results show that the proposed strategy that controls the BESS can improve the schedulability of the wind farm and maintain smooth output of wind/battery energy storage hybrid system meanwhile tracking the dispatching order.