Coordinated Planning of Hybrid Energy Storage System Based on Adaptive Decomposition Domain in Distribution Networks

The intermittent and stochastic nature of photovoltaic generation poses significant challenges to the stable operation of distribution networks. Therefore, a coordinated planning method based on the adaptive decomposition domain is proposed for hybrid energy storage systems (HESS) to address high power fluctuations. First, a bi-level optimization model is established for the HESS planning, where the upper level minimizes total lifecycle costs, while the lower level optimizes voltage deviation and network losses. In the lower-level operation optimization, the improved variational mode decomposition method is employed for fluctuating power decomposition, and then power reconstruction and allocation of HESS are realized based on the adaptive decomposition domain. Furthermore, the bi-level planning model is solved using an improved particle swarm optimization algorithm, achieving optimal site selection and capacity configuration of HESS. Finally, simulation results demonstrate that the planning method effectively reduces lifecycle costs, voltage fluctuations, and network losses, thereby improving both economic efficiency and system stability.