Research On Hydropower Reservoir Optimization Operation Considering Forecasting Inflow And Uncertainty

Chinese hydropower project has entered a key transition from construction to management with the rapid hydroelectric development.How to improve the utilization rate of water resources without changing the scale of reservoir project is of great significance to promote economic and social sustainable development.As the decision-making of reservoirs mainly depends on the current available water and the available water in the future,researchers have devoted to the study of hydropower reservoir optimization operation considering forecasting inflow and uncertainty.However,these results are rarely used in practice due to the uncertainties of forecasting inflow.Thus,the inflow forecasting models for China's Hun River are constructed based on the quantitative precipitation forecasts information of the Global Forecast System(GFS).Then in order to study the economical characteristics of power generation in the two-stage hydropower station dispatching,Mathematical analysis is used.Finally,the Optimal Operation Model for hydropower station coupling short and medium-term information is established based on the above research.The primary achievements of this dissertation are as follows:(1)According to the characteristics of flood period and non-flood period in Hun basin,the corresponding runoff forecasting models are established respectively.The 10 d precipitation forecasts of GFS are used to drive the runoff forecasting model.The results show that 5d runoff forecast is relatively good and the uncertainty of runoff forecast is increasing with the prediction period.To further improve the accuracy of middle-term runoff forecast,the key is to improve the accuracy of middle-term quantitative precipitation forecasts.(2)This paper considers the Tail Water Level(TWL)as a variable while hydropower scheduling,and explores economic characteristics of two-stage optimal hydropower scheduling with the changing TWL including the influencing factors,the change regularity,convexity,monotonicity and the rules of optimal-decision.The research shows that when there is a competitive relationship between the two-stage power generation,the optimal decision-making graph can give optimal decision-making under different state of reservoir based on the maximum benefit target of two-stage power generation.(3)By analyzing the characteristics of operation graph and the heading rules of the two-stage hydropower station dispatching,the Optimal Operation Model for hydropower station considering short and medium-term information is established in order to couple the information which owns different spatial scales.The simulation results demonstrate that the model can increase the power generation efficiency and reduce the discarded water without changing the statistical changes of the reservoir water level for many years.