Optimal Operational Strategies for Hydro–Wind–Solar–Pumped Storage Complementary Delivery Systems Under Extreme Renewable Generation Scenarios

To address peak-shaving challenges and power volatility induced by high-penetration renewable integration, this study proposes a hierarchical collaborative optimization framework for hydro-wind-solar-pumped storage delivery systems under extreme generation scenarios. A tri-level dispatch protocol (“renewable prioritization - diurnal storage cycling - seasonal hydraulic regulation”) is established, formulating an optimization model incorporating generation maximization, hydrodynamic equilibrium, and multi-physical constraints. Through 8760-h chronological simulations of a Yellow River upstream clean energy base, critical operational patterns emerge: consecutive low renewable generation during dry seasons triggers 10.6 m/day reservoir drawdowns necessitating emergency peak-shaving protocols; flood season high-level operations reduce spillage risks, limiting annual curtailment to 1.025 billion kWh; ecological dispatch periods (April-June) exhibit 1.75 m daily water-level fluctuations under pumped storage cycling, mandating hydraulic bounds (3241.75–3273.93 m) for storage performance optimization. The results demonstrate superior peak-shaving capacity and reduced curtailment versus conventional methods, offering a techno-economic paradigm for secure, efficient operation of renewable-dominated delivery systems.