Research On Reservoir Optimal Operation Oriented To Multidimensional Benefit Objective

Under the background of water shortages and increasing water use in river basins,the contradictions among various water use industries have become more and more prominent,and the competition for water use inside and outside the river is fierce.The research on the optimal operation of river basin reservoirs is of great significance for the rational distribution of water resources and the utilization of the optimal benefits of reservoirs.Based on the 13 th Five-Year National Key R&D Program Project "Key Technologies for Sediment Dynamic Control in the main tributaries of the Yellow River"(2018YFC0407400),this paper conducts a systematic study on the optimal dispatching of reservoirs in the river basin,and analyzes the Xiaolangdi Reservoir on the Yellow River as an example.The main research content and results are as follows:(1)The establishment of an optimal operation model for reservoirs with multidimensional benefit targets based on emergy theory.From the perspective of balanced regulation of multi-dimensional benefits,considering the value of production(industry and agriculture),life,ecological water resources calculated by emergy method,and the ecological flow threshold of the downstream reservoir quantified by Tennant method,the power generation benefit,comprehensive water shortage loss benefit,The ecological benefit objective function,combined with a series of constraints,respectively constructs the power generation-comprehensive water shortage twodimensional benefit target and power generation-comprehensive water shortageecological three-dimensional benefit target optimal dispatch model,and uses the NSGA-II evolutionary algorithm to optimize the model.(2)Optimal scheduling plan based on competitive relationship analysis and comprehensive evaluation of combination weighting.For the two-dimensional target scheduling model,based on the Pareto non-inferior solution basic program set,the target value sequence is fitted,and the two-dimensional target competition relationship is qualitatively and quantitatively analyzed;for the three-dimensional target scheduling model,the Copula function is used to analyze the three-dimensional target competition relationship.According to the analysis result of the target competition relationship,the extreme schemes are eliminated,and the three-dimensional target primary selection scheduling scheme set is obtained.Taking into account the subjective and objective weighting significance,a comprehensive evaluation method of analytic hierarchy and fuzzy comprehensive evaluation combined weighting is established to evaluate each plan of the primary selection plan set,and finally the optimal scheduling plan is selected.(3)Example analysis of Xiaolangdi Water Control Project.Based on the actual situation,a two-dimensional and three-dimensional target scheduling model is established,and then the multi-dimensional benefit target competition relationship is optimized and analyzed.The results show that: in the two-dimensional target scheduling model,the power generation benefit and the comprehensive water shortage loss benefit increase with the increase in water volume.Its competitive relationship is gradually weakening;in the three-dimensional target scheduling model,the power generation benefit and the comprehensive water shortage loss benefit are more competitive than the power generation benefit and the ecological benefit.For each increase in the ecological benefit by 100 million yuan,the comprehensive water shortage loss benefit in each typical year will increase respectively.It was 23.48,2.66,and 2.261 billion yuan.The power generation benefit and the comprehensive water shortage loss-the overall ecological benefit competition relationship is weak,and the competition trend of each typical year is: wet years are weaker than normal years and weaker than dry years.After increasing the ecological target,the remaining benefits become worse,especially the benefits of water supply.(4)Aiming at Model II,the schemes with the combined sequence value of comprehensive water shortage loss and ecological benefit greater than-3,-2.5 and-2are selected as the primary schemes in each typical year Through the analysis of the multi-dimensional benefit target competition relationship,and the number of schemes is 498,493 and 320 respectively.Construct a comprehensive indicator system for program evaluation covering the 7 aspects of safety,priority and efficiency,fairness,economy,society,ecological environment,and balance,using a combination of analytic hierarchy and entropy method for weighting,and using fuzzy comprehensive evaluation methods to centrally select from the primary selection programs The optimal plan is found,and the results show that the optimal scheduling plan for each typical year is the 273 th,330th,and 251 st plan.