1.School of Electrical Engineering, Shanghai University of Electric Power, Shanghai 200090, China;2.East China Electric Power Design Institute Co., Ltd. of China Eletrical Consulting Group, Shanghai 200001, China

According to the proposed operation model of hydrogen-power hybrid energy storage systems and secondary adjustment process of voltage-power droop characteristics in multi-terminal flexible DC distribution networks, a multi-time-scale optimal scheduling strategy for source-storage-network coordination is proposed. The objective of day-ahead scheduling is to minimize the operation cost and voltage deviation. It also optimizes the operation mode of hybrid energy storage, the on-off of micro-turbines and the secondary adjustment parameters of droop characteristics to provide the reference for intra-day optimal scheduling. Intra-day rolling optimal scheduling takes the economy as its objective to fine-tune the output power of equipment and compensate the power fluctuation caused by forecast errors. A case study is undertaken in an annular multi-terminal DC distribution network to verify the feasibility of the proposed scheduling strategy, the advantages of hybrid energy storage, and the improvement of operation by the secondary adjustment of droop characteristics.