金沙江下游梯级水库蓄水期多目标生态调度研究

Study on Multi-objective Ecological Operation of Cascade Reservoirs in the Lower Reaches of Jinshajiang River during Impoundment Period

随着乌东德、白鹤滩电站的陆续建设投运,金沙江下游梯级电站对河流生态影响日益突出。为减轻梯级水库蓄水对金沙江生态系统的不利影响,实现水能资源开发和生态环境双赢,进行金沙江下游梯级蓄水期联合生态调度。基于逐月最小生态径流计算法确定河流最小生态流量,以河流生态需水满足度最大和梯级发电量最大为目标建立多目标优化调度模型,并采用改进NSGA-Ⅱ算法对模型进行求解。结果表明,乌东德、白鹤滩投产运行将会导致蓄水期下游河流生态缺水情况更加严峻,优化梯级水库运行方式、适当提前蓄水可提高下游河流生态需水满足度,缓解梯级发电效益与生态效益之间的竞争关系。研究结果可为金沙江下游梯级水库蓄水期生态调度提供参考。

With the successive construction and operation of Wudongde and Baihetan hydropower stations,the cascade hydropower stations in the lower reaches of the Jinshajiang River have increasingly prominent impacts on river ecology.To alleviate the adverse effects of cascade reservoir impounding on Jinshajiang River ecosystem and achieve a win-win situation of hydropower resources development and ecological environment,ajoint ecological dispatch during impounding period was carried out.The minimum ecological flow of the river was calculated based on the month-by-month minimum ecological runoff calculation method.A multi-objective optimal dispatching model was established by maximizing the satisfaction of river ecological water demand and cascade power generation,and the model was solved by improved NSGA-Ⅱalgorithm.The results show that putting Wudongde and Baihetan into operation will lead to more severe ecological water shortage during the impounding period.Optimizing the operation mode and proper early impounding can improve the satisfaction of river ecological water demand and alleviate the competitive relationship between the benefits of cascade power generation and ecological benefits.The research results can provide reference for ecological dispatching of cascade reservoirs in the downstream of Jinshajiang River during impounding period.