基于完备经验模态分解与能量熵的混合储能系统功率分配

Power allocation of hybrid energy storage system based on complete ensemble empirical mode decomposition and energy entropy

基于超级电容-蓄电池构成的混合储能系统,本文采用完备经验模态分解的方法平滑风电波动。首先,针对风电波动性,采用完备经验模态分解求出不同的固有模态分量和余量,通过能量熵的理论求出功率分界点k值,进而确定初始功率分配指令;接着采用模糊控制理论对荷电状态进行约束优化,自适应调整并修正混合储能系统功率分配指令。算例分析表明,本文方法能够自适应实现功率的合理分配,混合储能系统工作在合理的荷电状态区间,有效提高系统的工作效率和使用寿命。

Based on the hybrid energy storage system composed of super capacitor and storage battery,the complete ensemble empirical mode decomposition with adaptive noise is used to smooth the wind power fluctuation in this paper.Firstly,according to the fluctuation of wind power,different natural mode components and allowances are obtained by the complete ensemble empirical mode decomposition.The power cut-off point k is calculated by the theory of energy entropy,and then the initial power allocation instruction is determined.Therefore,the state of charge has been constrained and optimized by the theory of fuzzy control,and the power allocation instruction of hybrid energy storage system is adjusted and modified adaptively.From the numerical example,the proposed method can adaptively realize the reasonable power distribution,and the hybrid energy storage system works in a reasonable range of charged states,which can effectively improve the system efficiency and service life.