1.College of Electrical Engineering, Zhejiang University, Hangzhou 310027, China;2.Ningbo Power Supply Company of State Grid Zhejiang Electric Power Co., Ltd., Ningbo 315121, China;3.State Grid Zhejiang Electric Power Co., Ltd., Hangzhou 310007, China

Frequent extreme weather events in recent years have increased the risk of water level control and capability operation in the hydropower enriched virtual power plant (HEVPP). First, to enhance the risk response ability of HEVPP on multiple time scales, an optimal operation model of HEVPP shared storage capacity considering the coupling of hydro-electric risk is proposed. Among them, the upper-layer model constructs a cross-month rolling optimization model considering the uncertainty of incoming water volume, decomposing the annual operation plan to obtain the end-of-month water level guidance boundary and monthly electricity plan. The lower-layer model proposes an overall risk description method for HEVPP based on the joint opportunity constraints of reserve capacity, constructs a monthly output and reserve model considering the deviation of hydro-electric operation, and forms a two-layer optimal model of HEVPP considering the end-of-month water level connection of shared storage capacity to deal with the potential hydro-electric risk during the rolling cycle. Then, based on the principle of risk sharing, a joint opportunity constraint transformation method for the monthly shared storage capacity in the lower-layer model is proposed, achieving the effective decoupling of HEVPP hydro-electric operation constraints. Finally, taking an HEVPP in Lishui City, Zhejiang Province, China as an example for numerical analysis. The results show that through rolling optimization of HEVPP operation plan, the multi-time-scale coupling of hydro-electric risk can be effectively dealt with, and the proposed reserve capacity allocation method can improve the water level control capability and economic benefits of each internal hydropower station.