The Study And Application For Optimal Operation Chart Of Cascade Reservoirs

With rapid development of giant cascade reservoirs construction,how to efficiently utilize these cascaded hydroelectric plant is becoming a imperative problem,and they are in urgent need of scientific and practical optimal operation chart for cascade reservoirs to guide.However,the current study focused on single reservoir operation chart,and effective method for drawing operation chart of cascaded hydroelectric plant is found seldom. Compared with single reservoir,simple variables and single target,cascade reservoirs posses properties of multi-dimension and multi-objective.How to joint the idea of united operation to operation chart in order to show the excellent advantage is difficulty.With the cascade hydropower stations in the Wujiang River as an example,this paper respectively use the implicit stochastic optimization scheduling algorithm and the dynamic programming successive approximation(DPSA) based simulation to study operation chart.Because the length of the runoff series is not long enough,the runoff process is simulated to offer more comprehensive information for making operation chart.The major research work is outlines as follows:1.The auto-regressive moving average(ARMA) model and the disaggregation model is proposed for the yearly and monthly runoff simulation of the cascaded hydroelectric plant on the Wujiang River.The analysis and test of the simulative runoff series are established and the result shows that the parameters are reasonable and the model is suitable for the stochastic generation.2.Implicit stochastic optimal operation method is used to drawing optimal operation chart of cascade reservoirs.First,the progressive optimality algorithm optimize the long runoff series.Then,based on result,operation function of decision-making variables and state variables is obtained using regression analysis.Finally,the total reservoir operation chart is worked out.3.In this paper,an approach of working out the optimal operation chart for cascade reservoirs is proposed and applied to highly developed Wujiang River hydropower system in China.Based on initial traditional operation charts both for single reservoir and for cascade reservoirs,power results of every single plant and cascade system are obtained.Then a load dispatching strategy of cascade reservoirs is used to regulate the power variance between the sum power of single plants and the power of cascade system.By using this program continuously,stimulant progress of history runoff data is obtained.On the basis of stimulant results,the dynamic programming successive approximation is used to modify the basic parameters of the two kinds of operation chart according to the objective of energy maximizing. By comparison with traditional effort,this approach can get integrative optimal operation charts for single reservoir and cascade system,and avoid fussy computation and repeatedly modification.The stimulant results indicate that the proposed approach is valuable and feasible by improving power generation benefits greatly considering the power grid require.Finally,a summary is given and some problems to be further studied are discussed.