Research and Application of Optimization Model for Reservoir Water Supply Regulation

Reservoir water supply regulation calculation is an important technical means to achieve rational spatial and temporal allocation of river water resources. The conventional reservoir water supply regulation calculation method has a clear process and simple operation, but the calculated water supply volume is not the optimal value. Aiming at the shortcomings of conventional water supply regulation method, an optimization model is constructed in order to improve the calculation accuracy of the reservoir water supply scale. The model’s goal is maximizing the total water supply of the reservoir during the calculation period, and it’s constraint contains the water supply guarantee rate and maximum damage depth of each water supply object. Based on the principle of equivalent transformation, the nonlinear constraint conditions of the water supply guarantee rate for water supply objects in the model are linearized, and Cplex linear solver is used to solve the model. The analysis results of Zhangfeng reservoir water supply project show that: Compared with the conventional method, the average annual water supply volume of Zhangfeng Reservoir calculated by the optimization model increases by 9.48 million m3, with an increase of 7.5%, and the water supply benefits increases significantly. The average water level of the reservoir decreases by 6 meters compared with the conventional method, and the number of changes in water storage and discharge increases, which fully utilizes the multi-year regulation effect of Zhangfeng Reservoir. The number of maximum damaged months for water supply objects is greater than that of the conventional method, but it still meets the design water supply guarantee rate requirements of each water supply object, indicating that the optimization model achieves the purpose of reducing the maximum damage depth by increasing the number of maximum damaged months. The average annual outflow rate decreases by 0.2 m3/s compared with the conventional method, but it can ensure that all months of the long series meet the ecological flow requirements within the river. The water shortage and water shortage process in two typical continuous dry periods from 1997 to 2002 and from 2008 to 2010 in the Qinhe River basin are similar to the results of the conventional method, which conforms to the actual situation and verifies the rationality of the model. The optimization model can modify the objectives and constraints according to actual needs, can accurately control the water supply guarantee rate and maximum damage depth of each water supply object, and also has portability, which makes it more flexible to use.