Study On The Influence Of Wicket Opening And Closure Law And Characteristics Of Turbine On The Transient Process Of Hydropower Station

Recent years, with the rapid development of hydroelectric projects in our country, a great number of hydropower stations with huge capacity, such as Longtan Project, Xiluodu Project, Xiangjiaba Project, Shuibuya Project and etc., are being designed or to be constructed. The mathematical simulation of transient process in hydropower stations is one of the most necessary investigations on this complicated dynamic system, which is constituted with pipeline system, hydraulic turbine and electric power transmission system. It plays a great role during the optimization design of pipeline system, safe and stable operations of power stations, and quality of power supply. Hydraulic turbine is the essential element in the operations of power plant, and also is the key point of mathematical simulation in transient process of hydropower station. Mainly around the hydraulic turbine, based on the research results of predecessors, this paper made some deep researches on wicket closure & opening law and characteristic curve of turbine. The main contents are as the following:Chapter 1, indicated the significance and objective of this paper, reviewed the achievements about transient process of hydropower stations, and then presented the study idea of this paper.Chapter 2, based on various stipulations about the wicket opening time in the relevant criteria at home and broad, the effect of wicket opening time of water turbine on the transient process of hydropower station has been analyzed by theoretical deduce and numerical calculation. The results of two practical calculation examples illustrates that the proposed opening time value by International Electrotechnical Commission (IEC) is suitable. That is to say, the doable value of load augment time is 30-40s.Chapter 3, beginning with the wicket linear closure law, two-sectionalized linear closure law of water turbine guide has been optimized by orthogonal method. Also some laws between the maximum dynamic pressure at the end of spiral case and the initial wicket opening are discussed. Then a conclusion has been obtained, the maximum dynamic pressure at the end of spiral case does not always occur during the operation case of maximum water head or nominal design head.Chapter 4, according to the numerical calculations of Longtan Project and Shuibuya Project, the difference of some crucial parameters during the transient process in hydropowerAbstractstation caused by various characteristic curves of turbine runners whose specific speed are close to each other has been contrasted in the respects of trait of turbine itself, the adaptability of turbine to water delivery system and electric power transmission system. And the results prove the fact is practical and suitable that some characteristics curve of hydraulic turbine with close special speed substitutes the real one as the boundary condition of the numerical emulation.Chapter 5, summarized this paper, and presented the aspect and emphasis on this study in future.