基于集合经验模态分解的混合储能系统功率分配

Power Allocation of Hybrid Energy Storage System Based on Ensemble Empirical Mode Decomposition

基于集合经验模态分解(EEMD)对风电波动进行平抑,提出了采用EEMD方法求解出不同的固有模态函数分量和余量。首先,通过信息熵理论求解出固有模态函数能量熵差值最大的阶次作为一个分界点;接着,通过样本熵理论求解出自我相似度最低的阶次作为另一个分界点,通过两个分界点得到初始的功率分配信号;最后,通过模糊控制优化理论对混合储能系统功率分配进行修正。算例分析表明,所提策略能够自适应实现功率合理分配和并网功率平滑,混合储能系统均工作在荷电状态合理区间,能有效提高系统运行稳定性和使用寿命。

Based on the adaptive ensemble empirical mode decomposition(EEMD),the new method was proposed to reduce the wind power fluctuation.Firstly,the order with the largest difference of the energy entropy of the intrinsic mode function was calculated by the information entropy theory.And then,the order with the lowest self-similarity was calculated by the sample entropy theory.At last,the power distribution of the hybrid energy storage system was modified by the theory of fuzzy control optimization.The results show that the proposed strategy can adaptively realize the reasonable power distribution and grid-connected power smoothing.And the hybrid energy storage system works in the reasonable range of the state of charge,which effectively improves the system stability and service life.