采用二次指数平滑的混合储能控制策略研究

Study on hybrid energy storage control strategy based on quadratic exponential smoothing

针对风力发电波动特性和储能电站安全问题,构建由水系锌基电池和超级电容组成的混合储能系统,提出基于二次变系数指数平滑算法的混合储能功率转移控制策略。首先,由于传统指数平滑算法的滞后性,提出基于调度目标波动与储能元件充放电限制功率的变系数二次指数平滑算法,获得二次指数平滑动态系数。其次,基于所得平滑系数对风电输出功率做二次平滑处理,得到目标并网参考功率与混合储能平抑功率。最后,将调度差值与储能元件实时荷电状态作为功率转移约束,提出混合储能功率转移控制策略,完成混合储能系统功率最优分配。仿真结果表明,所用混合储能系统提高了储能系统的安全性和综合循环寿命,所提算法能有效平滑风电输出,增强了风电波动平抑效果,同时实现了混合储能功率的合理分配,验证了所提算法和控制策略的有效性。

According to the fluctuation characteristics of wind power generation and the safety requirement of energy storage power stations,a hybrid energy storage system composed of aqueous zinc-based batteries and super capacitors is constructed,and a hybrid energy storage power transfer control strategy based on exponential smoothing algorithm with quadratic variable coefficient is proposed. Due to the hysteresis quality of the traditional exponential smoothing algorithm,a quadratic variable coefficient exponential smoothing algorithm for power limitation based on the dispatching target fluctuation and the charge and discharge of the energy storage element is proposed to obtain the quadratic exponential smoothing dynamic coefficient. On the basis of the obtained smoothing coefficient,the wind power output power is subjected to secondary smoothing treatment to obtain the target grid-connection reference power and the hybrid energy storage stabilization power. Finally,the dispatching difference value and the real-time state of charge of the energy storage element are taken as the power transfer constraints,and the hybrid energy storage power transfer control strategy is proposed to complete the optimal power allocation of the hybrid energy storage system. Simulation results show that the adopted hybrid energy storage system can improve its safety and comprehensive cycle life,the proposed algorithm can effectively smooth the wind power output,enhance the mitigation effect of wind power output fluctuation and realize the reasonable power distribution of the hybrid energy storage. To sum up,the effectiveness of the proposed algorithm and control strategy has been verified.