Optimization Method for Peak Shaving of Wind and Photovoltaic Power Generation Considering Integrated Pumped Storage Retrofitting in Cascaded Hydropower Systems

To achieve efficient multi-energy complementarity in cascaded hydro-wind-solar-pumped storage integrated power generation systems, this study investigates optimization methods for wind and solar power peak shaving considering the integration of pumped storage into cascaded hydropower stations. An accurate mathematical model of hydraulic dynamics is established with the objective of minimizing the standard deviation of residual load. Subsequently, the nonlinear relationships are linearized based on piecewise linear approximation, taking into account hydraulic linkage constraints, output limits of hydropower units, and output constraints of pumped storage units. Finally, the effectiveness of the proposed method is validated using a case study of a cascaded hydro-wind-solar-pumped storage hybrid system in southwestern China. The complementarity of the cascaded hydro-wind-solar-pumped storage integrated system is analyzed, and the peak shaving role of hybrid pumped storage in the integrated power generation system is illustrated through comparative analysis.