Short-term And Inner-plant Optimal Operation Of Cascade Hydropower Stations In Medium And Small Rivers

As a renewable clean energy,hydropower resources occupy a large proportion in energy composition of China.However,researches on optimilized operation are mainly focus on large-scale hydropower stations,but a few findings in small and medium rivers.There are many hydropower stations in small and medium-sized river of China,and their distribution patterns and operational characteristics are complex.Moreover,most of them lack scientific and reasonable optimization scheduling research.How to carry out optimal operation of cascade hydropower stations in small and medium-sized rivers to use water resources efficiently and improve waterpower utilization rate,are the technical difficulties that need to be overcome urgently,and the researches have important theoretical significance and application value.This paper is based on the theory of optimal regulation of daily regulating cascade reservoirs and the theory of optimal operation of day-adjusted cascade hydropower plants.Taking four small cascade hydropower stations in Suining,Sichuan Province as an example,Gunjundu,Longfeng,Xiaobaita and Sanxing.Based on the study of the key problems of the inflow distribution,tail water problem,flow delay law and characteristics,and time-of-use electricity price under the special connection mode of the reservoirs of the FuJiang cascade hydropower station,this study carried out the small-scale river-regulated cascade hydropower station.Group short-term and in-plant optimization scheduling research.The main research contents and results are as follows:(1)Aiming at the characteristics and requirements of short-term power generation dispatching of daily cascade hydropower stations,short-term optimal scheduling models for cascade hydropower stations are esTablelished,including the largest power generation benefit model and the largest power generation model.And the methods of solving short-term optimal dispatch of hydropower station group are proposed.(2)The tasks and contents of the economic operation of hydropower stations,the dynamic characteristics of hydropower stations are analyzed in this paper.And real-time economic operation mathematical models with the lowest total power consumption and maximum output of cascade hydropower stations are esTablelished.Then optimization algorithms of the economic operation model of hydropower plants are proposed.(3)Aiming at the short-term power generation dispatching problem of FuJiang cascade hydropower station,considering the water flow time lag,the dynamic water flow time-lag law of typical daily reservoirs are revealed in this study.And the influences of optimal scheduling of cascade reservoirs towards water flow time lag on are clarified.Based on special distribution patterns of hydropower station,flow distribution and tailwater problems are sloved.(4)The operation modes of each hydropower stations in FuJiang are drawed up.The short-term optimal scheduling models of the maximum power generation efficiency and maximum power generation of the Jundu,Samsung,Longfeng and Xiaobaita cascade hydropower stations are esTablelished.DPSA,POA-DPSA and Automatic Optimization Algorithms are used to solve the models.By comparation analysis of each scheme results,accuracy of the models and algorithms are verified and show that optimal scheduling improves the power generation efficiency of hydropower stations.(5)The optimal distribution models of the internal load of the FuJiang cascade hydropower stations are solved by equal micro-increasing rate method.Based on the analysis of the operating efficiency of each hydropower station unit,optimal load distribution results of each hydropower station and optimal operation strategys of the Dujundu and Samsung hydropower stations are obtained,which provide technical supports for the economic operation of cascade hydropower stations in FuJiang river basin.(6)Taking FuJiang cascade hydropower stations as the research objects,the dispatching and monitoring systems are integrated and the dispatching software platform are developed.Through the application of human-computer interaction interface in the software platform,the short-term optimal dispatching operation of the FuJiang cascade hydropower stations are realized and satisfactory operation results are obtained.