Strategies Research For Short-term And Real-time Optimal Operation In Qing River Cascade Hydropower Stations

Nowadays the cascade utilization of river basin water resources is forming and developing in China.To manage and control the hydropower stations and hydro-generators in a unified and centralized way,can release the benefits of joint regulation of cascade reservoirs,and improve economic performance of hydropower stations.Short-term and real-time optimal operation of cascade hydropower station system can form important basis for conducting unit safety operation,and satisfying the peaking load,output,outflow or water level demand of hydropower system.The short-term and real-time optimal operation problem has some typical characteristics like multiple decision,multi-dimension,complex constraints,huge scale and non-uniform scheduling subjects,it's also one of the research hotspot in optimal hydro operation field.Because of the complex characteristics,it's hard to find a way which can be applied to any hydro station systems to find an optimum operation solution.This article focuses on the problems in short-term and real-time optimal operation field,and selects cascade hydropower stations of Qing River in China as research object.By applying current theories,we analyze the problem,establish the operation model,and complete the calculation.The main research and achievement of this article include:(1)A load distribution for the generation unit is constructed,which aims at minimize the generation flow.A dynamic unit assembly table method is introduced,and the equal incremental equation is improved with heuristic method.This article combined these two methods to solve the load distribution for the generation unit problem.The dynamic unit assembly table is established on the unit minimum duration of on or off,and the water consumption rate of each unit,and it's also the foundation of selecting proper unit assembly for using the improved equal incremental equation.Heuristic method is used iteratively to make further revision to the calculation result of equal incremental equation.By regarding Geheyan hydro station as object for test and verification,the effectiveness of the model and calculate method is proved.(2)This chapter aims at cascade plants system,and elaborates the content and requirements of cascade plants non-real-time optimal operation.In this chapter,we build a cascade non-real-time load distribution model to minimize the cascade water energy consumption for generation.Firstly,successive load shedding algorithm is used to get the initial load curve for each hydropower station.Secondly,the cascade plants are divided into several dual subsystems according to upstream and downstream hydraulic connection,and POA is adopted to optimize within self-adaptive gallery between two stages.Thirdly,electric power and energy balance method is imported to adjust the power of remain period for fixing power generation deviation.The methods and strategies are proved to be valid within Qing cascade calculation case.(3)In this chapter,a model aimed at minimizing the cascade water energy consumption for generation is constructed.To satisfy the power flow requirement of transmission interface in power grid,a solution system is adopted.It includes station input sequence method,unit commitment strategy,load distribution among factories.Combined with load distribution method inner station mentioned above,the solution system realizes the fining load distribution plan requirement.The calculation test on Qing cascade has shown that the proposed algorithm can efficiently meet the requirements of cascade real-time load change,and successful to reduce the power generation deviation between real function process and daily plan.Finally,this part summarizes the research content of this artcle and puts forward the prospect of further elaboration.