水库水沙联合调度多目标风险分析方法与应用研究

Most previous studies about the combined regulation of flow and sediment in a reservoir were limited to a certain hydrological sediment condition and operation mode. However, the influence of uncertainty factors (such as hydraulic and hydrological factors, engineering state, human management etc.) on reservoir operation has not been well investigated. In this study, main risk factors of the coordinated operation will be identified and their joint distribution will be derived based on Copula function or Maximum Entropy method. A multi-objective risk decision-making model for the coordinated regulation of flow and sediment in a reservoir will be developed by using reservoir operation method, computation of sediment deposition of reservoir, risk analysis and the theory and technology of multi-objective decision-making etc. The solution and decision methods of the model will be studied in detail. The model can quantify the risks of flood control, generation and sedimentation of the coordinated regulation. The contradiction between risks and benefits of reservoir will be reconciled, and an optimal operation scheme of reservoir regulation will be obtained. The proposed model and corresponding solution methods are used to analyze the risks of the coordinated regulation in a multi-purpose large reservoir. Flow and sediment operation schemes will be put forward in order to decrease sedimentation risk and increase the dispatching abilities of reservoir. This research supplies the theory foundation and technology support for improving risk management of reservoir opreration, obtaining reservoir best comprehensive benefit and realize reservoir Long-term effective operation.

考虑水文、泥沙、工程状态以及人为管理等不确定性因素对水库水沙联合调度的影响，申请项目有机结合水库调度、水库泥沙冲淤计算、风险分析、多目标决策理论与技术等方法，对水库水沙联合调度中的主要风险进行识别、估计、评价和决策；重点研究主要风险因子识别与其特征机理、多维风险变量联合分布估计、水库水沙联合调度多目标风险调控模型与求解及决策方法等；提出水库水沙联合调度多目标风险分析方法，定量描述水库水沙调度过程中面临的主要风险，协调多目标效益转换和风险之间矛盾，以期达到水库防洪风险、发电风险与泥沙淤积风险之间最佳协调；并应用于实践验证，提出减少泥沙淤积风险、增加水库调蓄能力的水沙调度模式。研究成果将为提高水库调度风险管理、延长水库使用寿命、最大限度发挥水库综合效益提供理论基础和技术支持。

目前水库水沙调度研究大多针对某一确定性的水沙条件和工程运用条件，很少考虑不确定性因素对水沙调度的影响，因此研究水库水沙调度多目标风险分析方法具有重要的意义。本项目首先辨识了水库水沙调度主要风险因子，提出了一种基于多维Copula函数的水沙过程随机模拟方法，对入库水沙不确定性进行量化；然后对水沙调度的风险率和风险损失进行了估计，采用风险价值量化水沙调度方案对应的最大风险损失；再从风险、效益、损失三方面建立了水库水沙调度方案风险评价指标体系，提出了一种基于理想解的改进灰色关联度法对方案进行综合评价；又以一维非恒定、非均匀沙和不平衡输沙模型为基础，建立了水库泥沙冲淤数学模型，在对模型进行验证的基础上，将模型应用溪洛渡、向家坝水库泥沙淤积过程模拟中，分析了溪洛渡、向家坝水库泥沙淤积规律；接着，将风险价值引入到水沙多目标优化调度模型目标函数中，建立了一种考虑风险损失的水库水沙多目标优化调度模型，实现对水沙调度过程中风险、效益和损失的多目标调控，并重点研究了模型非劣解生成的嵌套结构的逐次逼近多目标并行动态规划迭代算法和大系统多目标递阶分析的“分解—聚合”算法；最后将上述模型和方法应用于溪洛渡-向家坝梯级水库水沙调度研究中，给出了不同置信水平与风险态度下溪洛渡-向家坝梯级水库的最优水沙调度策略。研究成果可为提高水库水沙调度风险管理、获取工程最佳综合效益提供理论基础和技术支持。