Refined Scheduling Of Cascaded Hydropower Stations Downstream JinSha River And Its Decision Support System

Along with the construction and operation of large-scale cascade giant hydropower stations in China, cascade hydropower stations are forming in most river basins. Mover over, the transmission pattern of electricity from western to eastern region, hybrid grid interconnection and unified scheduling of basin water resources has been initially established, which promotes the hydropower engineering in China transferring from the phase of project construction to operation management. In this case, the key to realize the efficient utilization of water resources is focused on joint optimization operation of cascade hydropower stations, which aims at exploring the elaborating management methods of water resources and developing comprehensive benefit of joint dispatching of cascade hydropower stations. With the constraints of hydrological meteorology, command of safe and stable operation of hydropower station, integrated regional water demand and power grid scheduling, the optimal operation of cascade hydropower stations is considered to be a kind of multidimensional, non-convex and complex nonlinear constraint optimization problem, combined with close relationship of hydraulic and electric power between cascade hydropower stations and complex relationship of the hydro-electric energy conversion. What's more, modeling and solution studied in the thesis have been a hot and difficult research topic in the field of water resources management. Centering on some key problems of joint refined operation of cascade hydropower stations, this thesis is researched on modeling theory and methods under the instruction of hydropower energy, intelligent optimization theory and engineering system. Finally, some key issues on system integration are solved and the Jinsha River water resources management integration platform is established in JinSha Dispatch Center based on the research achievements mentioned above, which provides theoretical basis and decision support for the scheduling of cascade hydropower stations downstream Jinsha River. The main content of this thesis and innovative achievement are as follows:(1) To meet the demand of generation scheduling of cascade hydropower stations for refined generation dispatch model, this thesis puts forward an refined generation dispatch modeling method for cascade hydropower stations. With the combination of theoretical analysis and statistical analysis, we have studied the effect of the time scale on accuracy of generation dispatch model, which contributes to proposing the multi-scale modeling method of the cascade hydropower stations. Meanwhile, after fully considering the daily operation mode of power station and the influence of water head and flow on synthesis efficiency coefficient, we put forward a refined hydropower calculation method for medium and long term dispatch, which helps build the refined generation dispatch model for cascade hydropower stations. Case study shows that the proposed model can effectively reduce the size of the dispatch problem and provide accurate and practical generation dispatch calculation for cascade hydropower stations downstream Jinsha River, guaranteeing of accuracy of dispatch model.(2) Based on mathematical characteristics analysis of two-stage optimal problem for cascade hydropower stations, the monotone principle of two stage optimal problem and its existence conditions have been ascertained, and a strategy of solution rapid adjustment regarding the principle of monotone principle is proposed accordingly. Meanwhile, a multi-population ant colony optimization is proposed in which the search ability is effectively enhanced by introducing multi-population and Gaussian group selection strategy. Furthermore, combined with the solution rapid adjustment strategy mentioned above, circulatory solution correction strategy for dealing with complex constraints is applied to improve the local search ability of this algorithm. The simulation results show that the proposed method is an efficient for solving joint optimization dispatch model of cascade hydropower stations with fast convergent rate, strong robustness, and the ability of searching solution closer to the global optimal solution than any other methods that are currently widely used.(3) According to the actual engineering requirements of researching on joint operation of cascade hydropower stations downstream Jinsha River, the annual and interannual distribution characteristics of streamflow during dry season of Jinsha River have been analyzed. The water-level-fluctuating criterion is ascertained to confirm the operation pattern of cascade hydropower stations during dry season based on the monotone principle of two-stage optimal problem, in order to propose the method of making water-level-fluctuating standards of cascade hydropower stations during dry season. On the basis of comprehensive analysis of the dispatch rules and results of long series flow routing, we have proposed the operation mode of cascade hydropower stations during dry season and joint water-level-fluctuating criterion in the period of pre-flood season. Simulation results prove that the standards formulated can maximize hydropower benefit and balance the hydropower benefit and water storage benefit of cascade hydropower stations in dry season. Therefore, it can provide the reference for actual operation of cascade hydropower stations in dry season.(4) In response to the actual engineering requirements of joint dispatch decision support system (DSS), we have designed object oriented system libraries for optimization operation of cascade hydropower stations guided by the theory of the research results above. We have proposed an application software system framework with three layer which consist of presentation layer based on the MVVM framework, service-oriented loose coupling business layer and multivariate-heterogeneous data oriented universal data layer. Functions including chart-database-table linkage of the presentation layer controls, loosely-coupled integration of business operations such as hydrological forecast and optimization schedule, distributed remote access and distributed data storage of different positions and different types of database among power plants and center of ladder have been realized. Furthermore, on the basis of thorough analysis of business process and related functional requirements for daily dispatch of cascade hydropower stations downstream Jinsha River, we have developed the platform for cascade hydropower stations scheduling downstream Jinsha River with intellectual property rights and core technology. The system testing results show that the build system is fully functioning, has good performance on human-computer interaction, and meets the design requirements for security and stability. What's more, performance of practical engineering application shows that the system satisfies the need for operation and management in cascade generation production downstream JinSha River in stable and reliable circumstance.