Reservoir Ecological Operation Model Under Hydrological Variation

Water is an essential resource for human production and life,but its natural state isn't completely in conformity with the needs of human,in order to carry out more reasonable temporal and spatial distribution of water resources,more reasonable control flow,reduce the occurrence of flood disaster,meet the purpose of promote the beneficial and abolish the harmful,a large number of water conservancy projects have been built,it is undeniable that the construction of water conservancy projects to meet the growing energy needs of the community,effectively reducing the occurrence of water disasters,but its ecological problems are becoming increasingly prominent.Reservoir is the most representative water conservancy project,its ecological problem has become a hot research topic in recent years,the construction of the reservoir changed the original movement of the river,block the river connectivity,the corresponding hydrological indexes have changed greatly,such as hydrological characteristics,physical and chemical characteristics,river morphology and coastal ecology,in order to reduce the effect of reservoir on river ecological system,aiming at the problem of ecological reservoir,considering the influence of hydrological variability,taking the Nierji reservoir as an example,the reservoir ecological scheduling model under the condition of hydrological variation is established,its main research contents are as follows:(1)Combined hydrologic variation diagnosis system,the human disturbance as the main cause of variation,through the preliminary diagnosis,detailed diagnosis and comprehensive diagnosis,to determine the variation nodes of selected hydrological time series,and divide the hydrological time series into three categories: hydrological sequence in natural state,to calculate the ecological flow in natural state;hydrological sequence with less human disturbance,to calculate the ecological flow in unnatural state;hydrological sequence with more human disturbance,to calculate the ecological flow in current situation.ice storage period(2)The hydrological index method is used to solve the ecological flow,and the month-by-month frequency calculation method is taken as reference,reduce time scale,and in ice storage period,select the month as a time scale,in non-ice storage period,select ten days as a time scale,calculated maximum ecological flow,suitable ecological flow,minimum ecological flow under the natural state,sub-natural state,current conditions,and the ecological flow without hydrological variation was taken as the control group,and using Tennant method to evaluate the obtained result.(3)The maximum amount of electricity generation as a goal,the water balance,the water balance,the water level,the maximum flow rate of the turbine,the output of the hydropower station,the output characteristics of the hydropower station and the ecological flow as the constraint condition,the FA algorithm is used to solve the problem,the ecological scheduling model of the reservoir and the ecological scheduling model under the condition of insufficient ecological restraint are established.(4)Taking the minimum and suitable ecological flow in four states as the lower threshold of the reservoir discharge flow and the maximum ecological flow as the upper threshold of the reservoir discharge flow,the conventional ecological scheduling of reservoirs in five typical hydrological years is carried out,the differences between the scheduling results of the hydrological variation and the original scheduling principle and the scheduling results without considering the ecological variability are analyzed.(5)Aiming at the situation that the partial scheduling result satisfies the minimum ecological flow constraint and does not satisfy the suitable ecological flow constraint,a non-sufficient ecological constraint flow method is proposed based on the scheduling result with the minimum ecological flow constraint and the ecological flow constraint is approached to The minimum ecological constraint flow is the lower limit and the non-sufficient ecological constraint flow is the upper limit.The relationship between the generating capacity and the ecological guarantee degree is established by introducing the slack variable ?.The Kmin method and the Kmax-1 method are combined with the Tennant evaluation to determine the non-sufficient ecological constraint Optimal Balance of Ecological Dispatch of Reservoir.The results showed,the original river ecological system was not protected effectively under the existing dispatching rules,water is not reasonable used in wet year;Reservior Ecological Operation under Condition of Hydrological Variability,a low ecological assurance level scheduling scheme was provided in dry year,reduce the degree of damage to the river ecosystem;The contradiction between economic benefit and ecological objectives is more obvious in dry season,and it effectively alleviated in wet season;There is still much room for improvement about the ecological flow constraint value,not directly select the scheduling result minimum ecological flow constraints as scheduling scheme;new scheduling model can effectively solve this kind of eco-scheduling problem situation,which provide decision makers with more reasonable operation mode,respectively,in the ecological six under ecological constraints guarantee degree can be increased by 60%,80%,40%,60%,70%,70%,accordingly,the rate of energy loss is only 2.01%,1.13%,1.28%,1.47%,2.16% 2.08%.