Capacity allocation of hybrid energy storage system based on VMD-GRGC ensemble methods

The hybrid energy storage system (HESS) consists of energy storage and power storage, is an effective solution to smooth the fluctuation of wind power. This paper proposed a means using variational mode decomposition (VMD) and grey relational grades cluster (GRGC) to obtain power and capacity allocation of HESS. First, moving average filtering was used to obtain the grid connected power and the reference power of HESS. The reference power of HESS was decomposed into subsequences by means of VMD, and the GRGC is used to reconstruct the subsequences into low frequency and high frequency components. Then the low frequency and high frequency components are used as power instructions for energy storage and power storage respectively. Considering the state of charge (SOC) and operating life of HESS, establish the annual minimum cost model. The results verified the effectiveness of the proposed method.