基于动态规划的电池储能系统削峰填谷实时优化

Load Shift Real-time Optimization Strategy of Battery Energy Storage System Based on Dynamic Programming

削峰填谷是电池储能系统的基本功能之一。为了更好地发挥储能系统作用、延长电池使用寿命,削峰填谷优化需综合考虑电池容量和充放电次数、变流器出力、实时负荷曲线、与储能系统其他控制功能相配合等因素。文中提出一种基于动态规划的实时修正优化控制策略,可在优化模型中引入充放电次数限制和放电深度限制等非连续约束条件,并通过将电池电量离散化等方法解决含有非连续约束的优化问题。同时,针对电网扰动等因素引起的储能系统其他控制功能动作导致的电池可用容量不确定变化,通过在线修正的方法加以解决。上述控制算法已成功应用于南方电网兆瓦级锂离子电池储能示范工程。以该系统所在的深圳碧岭站负荷实测数据为基础,对所设计控制策略进行了验证,说明了其良好的优化效果。

Peak shaving is one of the most important applications of battery energy storage system （BESS）. In order to fully make use of the battery as well as prolong the battery life, in the load shift optimization, many factors should be considered such as battery capacity, times of charge and discharge, load curve and the coordination with other applications of battery energy storage system. A real-time optimization strategy based on the dynamic programming is presented. Constraints like times of charge-discharge and depth of discharge are added to the optimization model. Dynamic programming is employed to solve discontinuous constraints problem when discrete BESS power adjustment is considered. BESS may also respond in other control modes or functions to the power system disturbances or fluctuations, which may result in unpredictable capacity variations..The real-time optimization strategy can be used to correct the battery capacity online. The strategy mentioned above is successfully applied to a MW-level BESS demonstration project in Biling substation, China Southern Power Grid. The results of the simulations and field tests based on the actual load data of Biling substation demonstrate the effectiveness of the optimization strategy.