Abstract: According to the multi-functional application requirements of large-scale energy storage technology on the grid side， the planning problem of the grid-side energy storage system is decomposed into two levels， namely multi-site selection of the energy storage system and optimal allocation of power capacity. At the multi-site location level of the energy storage system， combined with the multi-functional requirements of the energy storage system on the grid side， combined with system stability and economy， on the basis of the line load rate， network loss sensitivity， voltage sensitivity， and taking into account the timing of the indicators， a multi-attribute comprehensive index evaluation model is constructed. At the level of optimization power capacity configuration of multi-point layout energy storage system， a two-level programming mathematical model is established. The outer layer considers delaying the upgrade income of transmission line， reducing system network-loss income， energy storage investment costs， and system operation costs to configure energy storage. The goal is to maximize the net profit of the system， and optimize the layout of energy-storage power and capacity at multiple points. The inner layer optimizes the source and storage operation curves with the goal of minimizing the operating cost after the energy storage is configured. Finally， the validity of the proposed model is verified on the basis of an improved IEEE 24-node calculation example， which lays the foundation for large-scale energy storage planning on the grid side.

Key words: timing sensitivity, comprehensive index, delay expansion, two-layer model, energy storage site configuration