Optimal Operation Of Reservoirs In The Middle And Lower Reaches Of Lancang River Considering Runoff Uncertainty

Hydropower resources are a kind of clean and renewable energy,and use of hydropower can effectively reduce the damage to the ecological environment.The development of hydropower resources also has significant benefits for power generation,flood control,irrigation,shipping,water supply,etc.This article takes Xiaowan-Jinghong Dam section of the middle and lower reaches of Lancang River as the research objects.Firstly,an improved genetic algorithm is used to solve the optimal dispatch model of casdade reservoir with power generation as the target.Secondly,the historical runoff is simulated by Copula function and Gibbs sampling,and the transition matrix between adjacent months is constructed by Markov chain.Use the method of mathematical statistics to analyze the interval range of outflow and inflow,and construct a stochastic reservoir optimal operation model.Finally,the stochastic dynamic programming scheduling rules are extracted.The research content and results of this article are as follows:(1)Statistical distribution,Kendal rank test,R/S and other methods are used to analyze the runoff law in the study area.The results show that the inflow of the Dachaoshan and below reservoirs have a significant decreasing trend.There is no variation in water runoff,and the consistency of runoff sequence is reliable.(2)Taking the dam section of Xiaowan-Jinghong Hydropower Station as the research object,based on the improved genetic algorithm to construct and solve the optimal dispatch model of the reservoir group with the cascade power generation as the objective function,the optimal dispatch of the reservoir group is analyzed from the optimization results of typical years and long series Power generation benefits.(3)Four common univariate distribution functions are used to fit the monthly runoff density probability curve.Based on the Copula function fitting,the optimal distribution of each month is selected.Combined with the principle of Gibbs sampling,the optimal Copula function between adjacent months is converted into a conditional function.Randomly generate a large amount of monthly runoff,and test the reliability of runoff through correlation coefficients.(4)In view of the uncertainty of incoming water,the monthly runoff based on Copula function simulation,using the Markov chain and transfer matrix method to describe the transfer probability of incoming runoff,construct a stochastic dynamic programming model with power generation as the target,and solve the scheduling of Xiaowan Hydropower Station The rules are compared and analyzed with historical dynamic planning and deterministic dynamic planning,and the SDP-GA nested model is used to explore the impact of uncertain stochastic programming and scheduling on cascade reservoir.