Research On Joint Operation Of Reservoir Group Based On Runoff Forecast In Critical Period

With the continuous development of society and economy,in order to solve the problem of regional water shortage,China has built many inter-basin water transfer projects.The joint optimal dispatch of inter-basin water transfer projects needs to take into account the requirements of flood control,water supply,power generation,and ecological environment of water supply and water-receiving basin reservoirs(groups),which is difficult to solve and make decisions.At present,the study on decision-making of water diversion of inter-basin water diversion projects has achieved fruitful research results.However,the existing inter-basin water transfer project joint scheduling model is too complex,the decision-making forecast period is too short,the operation is relatively cumbersome,and it is not convenient for practical application.The abundance and dryness characteristics of the runoff in the reservoir during the year are often the same as the runoff in the wet season,and whether the water abandonment occurs after the water diversion in the water-receiving basin during the year depends on the scheduling decision during the wet season of the year.Therefore,this thesis will take the DHF inter-basin water diversion project(D reservoir is the water-receiving basin and HJ basin cascade reservoir group)as the research background to carry out the joint optimal operation of the cross-basin reservoir group based on the critical period runoff forecast and diversion constraints.The research first analyzes the law of inflow of water supply and receiving basin and its complementarity law;secondly,the research on the inflow forecast method of D Reservoir during the critical period of diversion(from May to October)is carried out;then,the runoff forecast information based on the critical period of diversion is carried out D Reservoir diversion dispatching research;finally,based on the diversion decision strategy,the HJ cascade reservoir group power dispatching research is carried out.The main results of the research are as follows:(1)Research on the inflow law and complementary characteristics of HJ cascade reservoir group and D reservoir.Aiming at the problems of complex scheduling and low water resource utilization in the joint operation of the water supply and receiving basins of the DHF cross-basin water diversion project,the paper analyzes the law of water supply and the inflow of the receiving basin and the compensation characteristics,and proposes the first study based on water diversion.The D Reservoir diversion dispatching of runoff in the critical period will then be based on the diversion decision strategy to study the research ideas of the HJ cascade reservoir group power dispatching.(2)Research on the runoff forecast for the critical period of D Reservoir diversion(from May to October).First,a BP neural network model(GA-BP)and a SVM model(GA-SVM)coupled with genetic algorithm were constructed;then,the random forest model,mutual information method,and correlation coefficient method were used to screen predictors as input to the model;finally,Compare and analyze the results of various forecasting methods.The results show that the forecast results of the GA-SVM model are the best with the predictive factors screened by random forest as input.The qualified rate of the forecast results is 80%and above,and the forecast magnitude is not different from the actual magnitude.More than one level.(3)Research on the optimal operation method of D reservoir based on the forecast information in the critical period of diversion.First,establish a scheduling model with the minimum diversion volume as the objective function;then,use the step-by-step optimization algorithm(POA)to optimize the conventional scheduling mode and the scheduling mode coupled with runoff forecast information during the critical period of diversion,and formulate scheduling rules;finally,comparative analysis Regular dispatch and forecast dispatch results,and analyze the impact of forecast errors on reservoir operation dispatch.The results show that the D Reservoir considers the water diversion optimization scheduling of the critical period of water diversion forecast information.Compared with the conventional diversion optimization scheduling,the multi-year average water diversion volume is reduced by 139.28×10~6 m~3,which is about 7.9%,and the multi-year average water discarded volume is reduced by 134.35×10~6m~3.About 32.1%,which not only improves the efficiency of water diversion,but also improves the utilization rate of local water resources.(4)Research on power generation dispatch of HJ cascade reservoir group based on water diversion decision strategy.First,the D reservoir diversion dispatching decision based on the runoff forecast information in the critical period of diversion is used as a constraint to optimize the power generation dispatching of the HJ cascade reservoir group to obtain an optimized dispatch diagram;secondly,to optimize the dispatch of the HJ cascade reservoir group to obtain the time period of the year.Water supply volume;Then,using the available water volume of the HJ cascade reservoir group as input,re-optimize the D reservoir water diversion scheduling rules;finally,use the conventional scheduling and optimized scheduling methods to perform joint scheduling on the entire system,and compare and analyze the scheduling results.The results show that the combined dispatch of the water supply and the receiving basin of the DHF cross-basin water diversion project.Compared with conventional dispatch,the use of optimized dispatch has greatly improved the water resource utilization efficiency of the entire system,and the multi-year average power generation of HJ cascade reservoirs has increased by 0.71×10~8kw·h,about 9.8%,the annual average water diversion volume of D Reservoir has been reduced by 150.8×10~6 m~3,about 9.8%,and the waste water volume has been reduced by 134×10~6 m~3,about 28.2%,and the water supply volume and water supply guarantee rate are both improved.