基于年防洪标准的水库分期优化调度研究

Research on optimized reservoir staged operation based on annual flood control standard

以棉花滩水库为例,在不降低年防洪标准的前提下进行汛限水位分期优化调度。采用传统水文频率分析法推求分期设计洪水,分期洪水组合概率应与年洪水概率一致;建立分期设计洪水频率与相应防洪库容的两变量序列,根据拟定汛限水位的防洪库容插值求得防洪风险率;在分期防洪风险率组合满足年防洪标准的前提下,根据发电、调洪规则及其它约束条件进行长系列模拟,对各分期进行风险和效益转移,寻求整体最大效益。结果表明:汛限水位前汛期取168.78 m、后汛期取169.58 m,防洪风险率分别为1.217%、0.783%,组合风险率为1.99%;与年防洪标准2%基本一致,同时具有较大的兴利效益。

Taking Mianhuatan reservoir as an example,staged optimization operation without reducing annual flood control standard is implemented. Traditional hydrological frequency method is used to calculate stage design flood,and probability combination should be consistent with annual flood probability.Two variable sequences between staged design flood control capacity and frequency are established. The flood risk is calculated according to flood control capacity under staged limited water level. Under the premise that risk combination satisfied annual flood control standard,long series simulation is conducted based on power generation and flood regulation rules,to seek great overall benefit by transferring stage＇s risk and benefit. The results show that,limited water level in main and secondary flood season is 168. 78 m and 169. 58 m respectively,flood risk rate is namely 1. 217% and 0. 783%,whose combination risk ratio is 1. 99%,consistent with annual flood control standard 2%,and has greate benefit.