Deriving Optimal Refill Rules for Multi‐Purpose Reservoir Operation

This paper focuses on deriving optimal refill rules for a multi‐purpose reservoir, and aims to maximize utilization benefits under the condition of flood control safety. The entire flood season is divided into multiple sub‐seasons (i.e. pre‐flood season, main‐flood season and post‐flood season). By advancing the start of the refill period to the beginning of the post‐flood season, seasonal design flows during the new refill period are estimated. A multi‐objective refill operation model is proposed by combining flood control and conservation together. The simulation–optimization‐test framework and hybrid multi‐objective genetic algorithms are developed and used to optimize the rule curves. China’s Three Gorges Reservoir is selected as a case study and the application results show that the proposed model can increase the hydropower generation by 17.4%, decrease spilled water by 43.9%, and improve the refill probability greatly without decreasing the flood control standard and navigation probability during the refill period.