The Influence Of Hydroelectric Project Operation On Runoff

The study of the influence of the build and run of hydropower project on runoff is a foundational research project, which is very important in both theory and practice. The paper make a primary study on the effect of runoff from the ran of hydropower project and make some research result in method and theory, which based on the work done by the former.The mainly content includeIn section one, the background and significance of the project are introduced. It is involved the current study and the development on the effect of runoff from the ran of hydropower project.In section two, we focus on the research of The Three Gorges-Gezhouba and Qingjiang River cascade optimal operation. The author separates the optimal operation into two sorts, single-cascade optimal operation and joint cascade optimal operation.In section three the Grade-frequency method is presented to study the datas character of runoff coming from the Three Gorges hydropower station group. It introduced a quantitative parameter, which reflects the impact degree of reservoirs operation on runoff.The technology of wavelet analysis is introduced in section four. It is applied to investigate the variation trend of runoff coming from the Three Gorges hydropower stations. The result shows the secular trend of runoff series of Gaobazhou has been changed because of the adjustment ability of Shui BuYa reservoir and Geheyan reservoir on Qingjiang River.In section five, we maked a study on the complexity variety of runoff time series operated by the Three Gorges hydropower station group and do some work on the physical significance of the complexity of runoff time series. Judging from the algorithm complexity, the periodic variation of runoff is weakened under the regulating of Three Gorges reservoir and the randomicity of runoff is weakened under the operation of Shui BuYa reservoir and Geheyan reservoir. The raise of Lopez-Ruiz complexity reflects weaken of randomicity or periodic of runoff after the adjustment decreases and strengthen of chaos.In section six, the theory of pattern discovery is applied to study the temporal pattern of runoff. The sequence model of operated runoff is different with non-operated runoff on the Three Gorges, which reported that the appearance probability of the low flow state in state-transferring diagram decreases a little after the operation, that indicates the promotion on the runoff of non-flood seasons.In section seven, we draw a conclusion and present an overview for the further promising directions.