水库汛期运行水位动态控制风险和效益分析

Risk and Benefit Analysis of Dynamic Control of Reservoir Operation Water Level during Flood Season

摘要: 汛期运行水位动态控制可通过挖掘利用预报信息提高水库兴利效益，但需合理评估可能面临的防洪风险。在提出水库和下游防洪保护对象附加防洪风险概念的基础上，建立了水库面临不同量级预报入库洪水时的运行水位动态控制优化模型，并以三峡水库为例，分别选取丰、平、枯三个典型年进行了验证分析，结果表明：1) 丰水年可以增加发电量约4%，枯水年和平水年汛期最大可以增加发电量约8%和9%；2) 当水库预报入库洪峰流量小于66,000 m³/s，运行水位控制在151 m及以下时，城陵矶地区附加防洪风险率小于0.5%。给出的汛期运行水位、预报洪峰流量和城陵矶地区下游附加防洪风险之间的关系，可以为三峡水库的调度决策提供更为丰富的参考信息。

Abstract: The dynamic control of operating water level during the flood season can improve the benefit of reser-voir by exploiting the forecast information, but it is necessary to reasonably assess the possible flood risks. Based on the concept of additional flood control risks for reservoirs and downstream flood protection objects, an optimization model of operating water level dynamic control when reservoirs face different magnitudes of forecasted incoming floods is established. Then taking Three Gorges Reservoir as an example, three typical years of high, normal, and low were selected for verification analysis. The results showed that: 1) The generation capacity can be increased by about 4% in high flow years, and the maximum increase of power generation capacity can be about 8% and 9% during the flood season in normal and low flow years; 2) when the forecasted incoming flood flow of the reservoir is less than 66,000 m³/s and the operating water level is controlled at 151 m and below, the additional flood protection risk rate of Chenglingji area is less than 0.5%. The given relationships between the operating water level, the forecast flood flow and the additional flood risk in the downstream of the Chenglingji area can provide more reference information for the operation decision of the Three Gorges Reservoir.