Research On Multi-Objective Optimal Risk Operation Of Han Jiang To Wei River Water Division Project

At present,reservoir operation management has changed from a traditional single-objective to a multi-objective model gradually,especially in inter-basin water transfer projects which water transfer in the source area involves issues such as water transfer risks and river ecological risks in the source area and reservoir operation risks.Therefore,this paper takes research on multi-objective risk operation of inter-basin water transfer project that considers the ecological water demand in the water source area,and the results have important theoretical significance and application value for reservoir operation theory and technology of inter-basin water transfer project.Han Jiang to Wei River water division project in Shaanxi province is taken as the research object,the ecological water demand processes in the downstream of the Huangjinxia and Sanhekou reservoir in the water source area are calculated.The multi-objective deterministic optimal operation model considering ecology and economy obj ectives and the multi-objective risk optimization operation model considering the ecological risk-water transfer risk-year end water level risk are built.The relationships between the ecological objectives and the economic objectives under the different ecological water demand processes in the downstream are explored.Finaly,the Sanhekou Reservoir risk operation strategies are generated.The main research results obtained in this paper are as follows:(1)On the basis of considering the runoff inconsistency,a calculation and evaluation system for ecological water demand in the river is proposed,then an integrated framework for calculating the ecological water demand in the river considering the variation of runoff is constructed.The proposed framework is applied to calculate and evaluate the ecological water in the lower reaches of the Huangjinxia and Sanhekou reservoirs.(2)Based on the NSGA-? algorithm,the particle update strategy in PSO is used to replace the genetic operator operations generated by the offspring of NSGA-?,and combined with the NSGA-?elite preservation strategy,the fast non-dominated particle swarm NSPSO multi-objective optimization algorithm is proposed The feature of the algorithm is pronosed with the less calculation parameters and high calculation effect,which is performed with better convergence and consistency and stability.(3)Taking the minimum water shortage index of the river ecosystem in the water source area,the minimum water shortage index in the total water transfer process and the maximum multi-year average net power generation as the optimization objectives,a multi-objective optimal operation model for the reservoir-pumping station-power station group of the Han Jiang to Wei River water division project is established.The Pareto solution set with spatial interpolation is used to reveal the law of multi-object conversion between ecological objective and economic objectives,the functional relationship between the three goals and the two goals are established respectively.Finaly,the ecological reservoiroperation rules is generated with considering based on the modified ecological water demand process(4)The fuzzy probability and maximum entropy theory is used to defined three risk sources,including water transfer risk,ecology risk,and year-end water level risk.Taking the water transfer risk,minimum ecological risk,and year-end water level risk as the optimization objectives,a multi-objective optimal risk operation model for the reservoir-pumping station-power station group of the Han Jiang to Wei River water division project is established based on the ecological reservoir operation.The transformation relationship between water transfer risk,ecological risk and year-end water level risk is revealed,and the influencing factors of the year-end water level risk of Sanhekou reservoir are analyzed qualitatively.(5)Based on the Pareto solution set of the multi-objective risk operation model,the change process of the water transfer volume in different months is counted,and the water transfer law of the Huangjinxia reservoir is revealed.The reliability and vulnerability indicators are used to evaluate the water transfer process corresponding to the Pareto solution.Under considering the model target results,reliability and vulnerability index results synthetically,the water transfer scheme corresponding to the Pareto solution with the least water transfer risk is recommend(6)Based on the water transfer scheme with minimum risk,a multiple regression function is used to fit the reservoir function of the typical year and long series of Sanhekou reservoir.The Sanhekou reservoir risk operation chrt is generated including the restricted water supply area,guaranteed water supply area,increased water supply area and independent water supply area are generated inside.