Optimization Scheduling Method For Irrigation Systems With Two Reservoirs And Three Pumping Stations In Hilly Areas

In China,the spatial distribution of water resources is uneven,and the interannual variation of rainfall is very large,which makes it difficult to meet the water demand of regional agriculture,life and industry.The optimal allocation of water resources in time and space has become an urgent need to solve the problem of regional water use.In the hilly and mountainous areas of southern China,the optimal operation of the "reservoirs and pumping stations" water supply system is an important method and means to realize the rational allocation of water resources in time and space,and also an important content of regional water resources management,which can solve the problem of insufficient supply of water demand for water users.The operation and management of the "reservoirs and pumping stations" water supply system has naturally become the key to solving this problem.Therefore,it is urgent to study the optimal scheduling method of the "reservoirs and pumping stations" water supply system,so that the reservoir management personnel can scientifically manage the reservoir,realize the optimal dispatching of the water supply systems,and maximize the dispatching benefit.In this paper,the optimal scheduling method is studied for the "two reservoirs and three stations" irrigation system with two reservoirs in hilly and mountainous areas of Jiangsu Province,which each has a river water supply line,and there is a connected water supply line between the reservoirs.The objective function is to minimize the sum of squares of irrigation water shortage in each period of each irrigation area,and the constraints are the annual water supply of the system,the annual water supply of the pumping stations,the irrigation water supply in each period,the water supply capacity of the pumping stations and the improved reservoir optimal scheduling criterion,and the irrigation water supply in each period of the reservoir as the decision variable,the optimal scheduling model of the "two reservoirs and three pumping stations" irrigation system was constructed.According to the characteristics of the model,the large system optimization method based on experimental optimization is used to solve the optimal scheduling scheme.Taking the joint optimal operation of Shanhu Reservoir and Niqiao Reservoir in Liuhe District of Nanjing as an example,compared with the optimal operation scheme based on the conventional operation criterion,the optimal operation scheme based on the improved operation criterion:in the normal year,the amount of abandoned water in reservoirs was decreased by 269 000 m3,and the irrigation water shortage in irrigation areas was decreased by 553 000 m3,the number of water pumping of pumping stations was reduced,and the water storage of Shanhu Reservoir and Niqiao Reservoir was controlled at the end of the last period.In general drought years,the abandoned water of reservoirs was reduced by 881 000 m3,the irrigation water shortage of irrigation areas was reduced by 456 900 m3,and the number of water pumping of pumping stations was unchanged.At the end of the last period,the water storage of Shanhu Reservoir and Niqiao Reservoir returned to the initial water storage of 8.470 million m3 and 1.590 million m3 from 8.2031 million m3 and 1.7166 million m3 respectively.In the special drought year,the abandoned water of reservoirs was reduced by 146 400 m3,and the irrigation water shortage in irrigation areas was reduced by 2.4389 million m3,and the number of water pumping of pumping stations was reduced slightly.At the end of the last period,the water storage of Shanhu Reservoir and Niqiao Reservoir returned to the initial water storage of 8.470 million m3 and 1.590 million m3 from 10.1000 million m3 and 2.3671 million m3 respectively.It can be seen that the optimal scheduling method based on the improved scheduling criterion can effectively reduce the amount of abandoned water in reservoirs and increase the amount of irrigation water supply.At the same time,it can also give full play to the water lifting capacity of pumping stations and reduce water lifting times of pumping stations.In addition,it can also realize the demand for the specific value of reservoirs water storage at the end of the last period.According to the optimal scheduling method based on the improved scheduling criterion of "two reservoirs and three pumping stations" irrigation system,the graphical user interface(GUI)function of MATLAB R2022a was used to develop the module to obtain the decision support system for optimal scheduling of "two reservoirs and three pumping stations" irrigation system in hilly areas.The user inputs reservoirs characteristics of the scheduling year,the water lifting characteristics of the pumping station,the inflow and loss of water in each period of reservoirs,the irrigation water demand of irrigation areas,the parameters of the constraint of reservoirs optimal scheduling criterion,and the design values of the orthogonal test level on the graphical user interface.After the operation calculation of the optimal scheduling decision support system,the optimal scheduling scheme can be obtained.It is convenient for the management personnel of the "two reservoirs and three pumping stations" irrigation system to manage reservoirs and pumping stations,so as to maximize the benefits of the irrigation system.