Abstract: The bundling of hydro-wind-solar energies serves as an important guarantee for the large-scale,efficient and safe grid-connection of new energy resources,and is conducive to improving the efficiency of clean energy utilization,thus realizing the “double carbon vision target” at an early date;on the other hand,it will also aggravate the influence on the operation efficiency of hydropower units.In this paper,the effect of different new energy ratios on the efficiency of hydropower units under the hydro-wind-solar bundling mode is discussed.First,a daily-bundling dispatching model is constructed under hydro-wind-solar mode,and then a numerical example is given to study the virtual wind and photoelectric fields around the Wudongde dam.Results reveal that with the increase of new energy,the operating efficiency of hydropower units will decrease in dry season but increase first and then decrease in flood season.The fluctuation of the efficiency of hydropower units within a day in flood season is smaller than that in dry season.Consequently,hydro-wind-solar bundling in flood season is more favorable to improve the operation efficiency of hydropower units.

Key words: clean energy, hydro-wind-solar bundling, multi-energy complementarity, hydropower units, power unit efficiency, Wudongde hydropower station