Study On The Mid-long Term Generation Scheduling And Multi-Time-Scale Coupling Nested Model Of Cascade Hydropower Station

As China's advantageous resources,hydropower energy has been rapidly developed and utilized during the structural adjustment of the power industry in recent years.With the completion and operation of cascade hydropower stations in many river basins,hydropower has gradually become a pillar industry of national economic development.Under the current situation,China's large-scale hydropower station construction has come to an end,and the focus of work has begun to shift to the optimization of hydropower energy operation.Under the condition of uncertain inflow,the main objective of optimal operation of cascade hydropower stations is to make full use of runoff forecast,excavate the compensation adjustment mechanism between cascade hydropower stations,make rational and efficient use of water resources and improve the overall power generation.Based on the engineering background of Xiluodu and Xiangjiaba in the lower reaches of the Jinsha river,as well as the four cascade hydropower stations of the three gorges and Gezhouba in the upper reaches of the Yangtze river,this paper studies the joint optimal operation of cascade hydropower stations.The main research contents and results are as follows:(1)Efficient algorithm for solving the optimization problem of hydropower energy.Aiming at the precocity of standard gravity search algorithm,an improved Gravitational Search Algorithm based on quasi-oppositional learning is proposed.The benchmark function is used to test the improved algorithm.Experimental results show that the improved QOIGSA algorithm is superior to the standard GSA algorithm.The strategy of quasioppositional learning provides an optimal initial solution for the algorithm,and the ability of exploring and developing the algorithm is enhanced by destroying the gravitational operator.It provides a good solution for the limitation of the standard GSA algorithm in the application of the complex optimization problem of hydropower energy,which is easy to fall into local extremum.(2)Study on Mid-long term optimal operation of cascade hydropower stations.Establish Jinsha river downstream-the three gorges cascade joint optimization of imperial power generation scheduling model,and the cascade of imperial joint optimization scheduling optimization results with the creek-to the cascade,the three gorges cascade two joint scheduling optimization results contrast analysis,can make full use of cascade hydropower stations in the imperial alignment between the compensation adjustment function,through the upstream cascade speed down to reduce power generation,increase the capacity of downstream power station to increase the profit of the overall total of imperial power,fully reflects the joint optimization of cascade hydropower station scheduling advantage.(3)Study on multi-scale coupling and nesting of cascade hydropower stations.In view of the problem that the optimal operation models with different time scales are not closely related to each other in the actual operation of cascade hydropower station,the coupling nested operation mode with multiple time scales is studied,and the control and feedback relationship between the long time scale model and the short time scale model is analyzed.Taking the lower reaches of the Jinsha river and the four reservoirs of the three gorges as the research object,a three-layer nested optimal power generation scheduling model is established.Compared with the traditional optimal operation model,it is proved that the multi-time-scale coupling nested model is of guiding significance and practical value to the operation of cascade hydropower station.