三峡水库中小洪水调度性能风险评估

针对三峡水库汛期中小洪水资源利用中存在的防洪、发电、库区地质、航运、汛末下游供水及蓄满风险问题,分析了中小洪水特性,建立了各类风险指示函数,提出了三峡水库中小洪水调度性能风险评估方法;同时,结合三峡水库汛期初步设计方案和2008～2017年中小洪水调度实践方案,对比分析了初步设计方案与调度实践方案中关于汛期中小洪水调度性能风险及调度运用过程年际间的变化情况。研究结果表明:2008～2017年的10 a间,相较于初步设计方案,调度实践方案使汛期发电量共增加了853.7亿kW·h;防洪风险由0.53%上升至54.51%,汛末下游供水风险由54.65%下降至14.65%,蓄满风险由50.00%下降至40.00%;发电、航运及库区地质风险变化不大。

Risk assessment of medium and small flood dispatching performance of Three Gorges Reservoir

Flood resources utilization of medium and small floods during flood season in the Three Gorges Reservoir (TGR) bears potential risks, such as flood control, power generation, geological conditions in the reservoir area, navigation, downstream water supply and full storage risk during flood recession period. We analyzed characteristics of medium and small floods, established various risk indicating functions, and put forward risk assessment measures for flood dispatching performance; meanwhile, by comparing preliminary design scheme for TGR during flood season and 2008~2017 dispatching scheme for medium and small floods. We analyzed inter-annual variations in risk assessment of dispatching performance and its implementation. The results show that the 2008~2017 dispatching scheme helps increase power generation by 85.37 billion kW·h compared to the preliminary scheme; flood control risks rise from 0.53% to 54.51%, while risks in downstream water supplying decrease from 54.65% to 14.65%, and risk of having a full storage decreases from 50% to 40%, risk level for power generation, navigation and reservoir geological risk of reservoir areas remain about the same level.