Abstract: With the full liberalization of incremental distribution network operation right and the policy support for energy storage in the electricity marketization reform,it is an important issue to explore the operation potential of energy storage,discuss the compatibility and operation mode of assisting distribution system operators to participate in the electric power energy market and the reserve market,and improve the utilization rate of distributed energy storage and the operation economy of distribution network.Aiming at the storage capacity limitations of distributed energy storage and the operation environment in active distribution network,the reserve availability and accessibility constraints are established,respectively,and an operation strategy for active distribution networks considering the participation of energy storage in the energy-reserve joint market transaction is proposed.First,the overall operation model with the distribution system operator as the main player is elaborated.Then,the reserve capacity of the energy storage system is modeled to quantify the reserve continuous calling capacity with energy storage capacity constraints as well as the reserve capacity that can be delivered to the root node with power flow constraints.Considering the ability of energy storage to participate in the electric power energy market and the reserve ancillary service market,a two-layer optimal dispatch model of active distribution network under market environment is developed to improve the operation economy of distribution system operators and the utilization of energy storage.The simulation results demonstrate the effectiveness of the proposed strategy.