基于SE-improved SGMD的混合储能容量优化配置方法研究

Research on Optimal Configuration Method of Hybrid Energy Storage Capacity Based on SE⁃improved SGMD

采用混合储能系统平抑风电输出功率波动可有效解决风电并网问题,而不同功率分配方法对混合储能优化配置结果影响大,为此提出一种基于样本熵改进的辛几何模态分解方法(sample entropy-improved symplectic geometric mode decomposition,SE-improved SGMD)的混合储能系统功率分配策略。首先,采用SGMD对不平衡功率进行分解,获取一系列辛几何分量SGC(symplectic geometry component);然后,计算分解后各SGC的样本熵SE(sample entropy)并获取其相似度阈值,以此为依据将分解后的子分量重构高、低频分量,分别作为超级电容和全钒液流电池的参考功率;进而,通过计及储能设备SOC限幅约束和充放电效率约束对两种储能设备的额定功率和容量进行配置;最后,结合中国某风电场实测输出数据,构建基于全寿命周期成本的经济性评估模型,验证文中方法的有效性与实用性。

Using hybrid energy storage system to smooth out the output power of wind power can effectively solve the problem of wind power connection to the power grid,whereas different power allocation methods have great influence on the optimal configuration of hybrid energy storage.Therefore,a power allocation strategy of hybrid energy storage system based on sample entropy⁃improved symplectic geometric mode decomposition(SE⁃improved SGMD)is pro⁃posed.Firstly,SGMD is used to decompose the unbalance power so to obtain the Symplectic Geometry Component(SGC).Then,the sample entropy(SE)of each SGC after decomposition is calculated and its similarity threshold is obtained.Based on this,the decomposed sub⁃components are reconstructed into high and low frequency components,which are used as the reference power of super capacitor and vanadium redox flow battery respectively.Furthermore,the rated power and capacity of the two energy storage devices are configured by taking into account the SOC limit constraints and charge⁃discharge efficiency constraints of the energy storage devices.Finally,combined with the mea⁃sured output data of a domestic wind farm,an economic assessment model based on life cycle cost is constructed to verify the effectiveness and practicability of the method proposed in this paper.