面向长江中下游抗旱需求的上游水库群汛末联合蓄水调度研究

Aimming at the conflict between middle-lower Yangtze River drought resistance demand and the upstream reservoirs impounding in flood recession period, Jingshajiang downstream cascade reservoirs, Three Goreges cascade reservoirs and qingjiang cascade reservoirs joint impounding operation in flood recession period is researched in the study. Firstly, according to water supply and demand balance analysis, ascertain the flow, water level and total water condition of research channel sections under different drought frequency of middle-lower Yangtze River. And then, research the reservoirs’ impounding time, order and strategy by comprehensive considering their characteristic, runoff change and transfer rule. Then, balance the relationship of flood control, impounding and drought resistance to design reservoirs joint impounding operation chart. After that, establish reservoirs joint multi-objective impounding operation model based on the impounding operation chart which set enhancing drought resistance ability as main target, hightening the water level at the end of flood season and other benefits for secondary targets, ensuring flood control safety as strict constraint. Explore an efficient optimization method for the complex multi-objective model. Further, aimming at the uncertainty of runoff, establish impounding operation risks and benefits evaluation index system, and propose a fuzzy decision-making method as decision-making analysis tool. On this base, through reservoirs’ joint operation simulation and risk decision-making analysis for different degrees of drought, research the change rules of the benefits and risks interaction. This study has great significance to improve the Yangtze river water resources management under drought condition and protect the basin sustainable development.

针对长江中下游抗旱补水需求与上游大型水库群汛末蓄水之间的矛盾，以金沙江下游梯级、三峡梯级和清江梯级混联水库群为对象，开展汛末联合蓄水调度研究。通过水量供需平衡分析，确定长江中下游不同干旱频率水情下研究断面流量、水位及总补水量控制条件；结合各水库运行特性、天然来水变化和梯级间流量传递规律，研究水库群蓄放水时序和策略，进而权衡防洪、蓄水和抗旱补水三者关系，构建联合蓄水调度图；以调度图为基础，建立以增强抗旱补水能力为主要目标，提高汛末蓄水位及其它兴利效益为次要目标，保障防洪安全为严格约束的水库群联合蓄水调度模型，探索模型高效求解方法；进一步的，针对径流不确定性，构建蓄水调度方案风险与效益评价指标体系，提出模糊决策优选方法，通过不同干旱水情的蓄水调度模拟与风险决策分析，研究各类效益与风险相互响应的变化规律。该课题为提高干旱条件下长江流域水资源控制水平，保障流域可持续发展提供科学的理论依据。

针对长江中下游抗旱补水需求与上游大型水库群汛末蓄水之间的矛盾，以金沙江下游梯级、三峡梯级和清江梯级混联水库群为对象，开展汛末联合蓄水调度研究：1）基于实测降雨、径流资料，借助IPCC AR4中的大尺度气候模式，开展气候变化条件下的长江中下游通江湖泊降雨、径流时空变化规律研究，为上游水库群汛末蓄水调度提供长江中下游水文情势变化的理论依据；2）开展三峡水库汛限水位动态控制及汛末提前蓄水方式优化设计，明确长江中下游抗旱补水和生态流量边界条件，提出以9月21日起蓄、9月底控制水位160m的基于调度图的改进蓄水策略，既能充分保证三峡水库防洪安全，又能合理利用汛末来水，满足长江中下游抗旱补水要求，并有效提高水库汛末蓄满率；3）构建三峡-葛洲坝梯级水库多目标蓄水调度模型，提出针对此模型高效求解的两阶段约束动态规划法和基于反学习策略的改进多目标差分进化算法，并进一步分析揭示了三峡水库汛末蓄水位、梯级补水流量、梯级发电量和防洪风险之间相互影响的变化规律；4）开展金沙江下游梯级联合调度及汛末蓄水方式优化设计，探讨不同保证出力对梯级年发电调度的影响，确定当蓄水时机为溪洛渡9月1日、向家坝9月1日时，采用基于调度图的改进蓄水策略，既有助于缓解梯级水电站间蓄水矛盾，又有助于减少水电站出力在不同调度区之间大幅度来回跳动，实现下泄流量、出力过程稳定；5）进行三峡下游支流清江梯级水电站联合调度研究，提出基于二维嵌套动态规划算法的梯级发电调度模型优化求解方法，并进一步分析了各电站之间发电、弃水的相互影响关系。该课题研究成果可为提高干旱条件下长江流域水资源控制水平，保障流域可持续发展提供理论依据与方法指导。