Research In Optimal Scheduling Of Tiantang Cascaded Reservoir

After the rebuild of Tiantang cascaded hydropower station, the first station of it has been changed into a pumped-storage plant from a normal one. The old dispatching rules of TianTang cascaded hydropower station are not appropriate exactly any more, new rules should be found to realize the economic operation of the cascaded hydropower station. The economic operation of cascaded power station for TianTang includes three parts, which is the annual dispatching of TianTang reservoir, the operation of TianTang pumped-storage hydropower plant and the daily operation of No.2-5 step stations. The purpose of economic operation is obtaining the maximum profit by efficiently controlling the generate equipment with the limitation of security and reliability. To achieve the purpose, the TianTang hydro-system is divided into two subsystems based on the contents of TianTang station's economic operation in this paper. One of them is the pumped-storage station system, the other one is 2-5 step stations system. The math model of these two subsystems has been presented. As the practical real system is a typical large non-lineal system, in general, the decision-making optimization of this kind of system is too complex and difficult to get the best solution. Thus the optimizing algorithms have to keep the balance between the quality of the decision and the time to find the decision. With a view to the request of TianTang power stations, the dynamic programming is adopted as the main algorithm for real-time optimizing, which has been accelerated by off-line data calculation. By analyzing the result of application in experimental power stations, it can be proved that the model and the algorithm is able to meet the requirement of economic operation basically, which means the optimized decision can assure the pumped-storage power station's ability of regulating, and efficiently use the natural incoming water of TianTang reservoir to generate powers at the same time.