Water-sediment-energy joint operation model of large-scale reservoir group for sediment-laden rivers

Abstract

For sediment-laden rivers, sedimentation seriously affects hydropower generation, water supply and comprehensive benefits of reservoirs. The objective of this paper is to provide a scientific modeling method and solution algorithm for the water-sediment-energy joint optimal operation of large-scale reservoirs in the basin. The innovation of this paper is that the water-sediment-energy optimal operation model of large-scale reservoirs was established, which considers the difference of objectives, boundary conditions and hydrological characteristics in different locations and operation periods. A joint solution method combining Discrete Differential Dynamic Programming (DDDP), Dynamic Programming Successive Approximation (DPSA) and Large-Scale System Decomposition-Coordination (LSSDC), was proposed. Eight key reservoirs on the mainstream and tributaries of the Yellow River were selected as case studies. The proposed optimal algorithm was compared with the current. Results demonstrate that compared with the DDDP algorithm and the PSO algorithm, total economic benefits of reservoirs optimized by the joint solution method increase by 2.31% and 19.03%, respectively. The hydropower generation of the WJZ, GX, SMX and XLD Reservoirs increases, while the benefits of sediment flushing, flood control, ice jam flood control, water supply and ecology of cascade reservoirs keep unchanged. The joint method can provide a scientific reference for the water-sediment-energy joint optimal operation of large-scale reservoirs.