To improve the inertia level of the sending-end power grid and enhance its ability to cope with uncertainty

a transmission-storage collaborative planning model that considers inertia improvement and addresses multi-stage uncertainty is proposed. Firstly

based on the principles of robust optimization and the N−1 criterion

the node inertia calculation method for the power system is improved

and a frequency response model for multi-resource coordination is established. Secondly

a multi-objective

multi-stage stochastic-distributed robust transmission-storage collaborative planning model is proposed. In the first stage

the transmission network energy storage planning scheme is formulated with the goals of improving the inertia of the sending-end power grid and optimizing economic efficiency. In the second stage

the delivery and day-ahead scheduling plans are developed. In the third stage

the day-ahead scheduling results are adjusted. Finally

the model is verified using the IEEE 14-node DC sending-end power grid and the IEEE RTS-79-node multi-DC sending-end power grid. The results show that the improved node inertia calculation method can be used to better identify vulnerable nodes in the system and enhance the robustness of the planning outcomes. The proposed uncertainty model can avoid overly conservative or aggressive planning schemes

and compromise both the robustness and economic efficiency of the planning results.