入库洪水过程的不确定性是防洪调度重点防范的主要风险源,为合理评估梯级水库联合防洪调度过程中所面临的风险,构建了以主要目标和约束的破坏概率为要素的风险评价指标体系,在考虑洪水预报中偶然误差及上下游水库之间入流的相关关系基础上,提出了梯级水库群入库洪水过程随机模拟方法,并将洪水频率分级后构建了梯级水库群联合防洪调度风险估计模型,给出了基于模拟最大熵理论的求解方法.实际工程算例分析表明,该方法与模型合理可行,能够给出不同预报误差标准差时的风险率,具有一定的适用性,可为调度决策提供参考.
Flood control of cascade reservoirs faces certain risk due to the existence of runoff randomness,which is the major risk sources; To assess the joint flood control risks of cascade reservoirs,a risk evaluation index system was established for the main objectives and constraints failure probability.In considering the flood forecasting accidental error and the correlation between the upstream and downstream reservoir inflow,a flood stochastic simulation method was proposed in the range of standard deviation allowed.Through the classification of flood frequency,a risk analysis for flood control model and its solving method with Monte Carlo and maximum entropy theory were constructed.By the analysis of the joint scheduling of Three Gorges and Xiluodu as an example,it is shown that the method and model is reasonable,feasible and has a certain degree of adaptability.Especially it can estimate the risk of flood forecast error standard deviation,and provide an important basis for the scheduling decision.