梯级水库汛期运行水位联合动态控制及多维风险关联规律研究

In order to solve contradiction among flood control, power generation as well as impoundment in the field of operation and management for cascade reservoirs, a model for dynamic control of flood operating water level (FOWL), whose objectives are to maximize the power generation and impoundment rate as well as minimize flood control risk, deficient power generation risk and deficient impoundment risk in effective lead-time of hydrologic forecast is proposed based on aggregation-decomposition theory as well as refill and pre-release method, by identifying the flood control risk, deficient power generation risk and deficient impoundment risk. And then, analytical solution is presented for correlation equation of FOWL of three cascade reservoirs. Besides, equivalent exchange method of storage capacity is proposed to explore correlation rules among FOWL, flood control risk, deficient power generation risk and deficient impoundment risk by coupling storage capacity compensation and capacity-constrained pre-release method so as to provide risk constrains for risk analysis of flood control, power generation as well as impoundment based on Monte Carlo simulation. After that, asymmetrical rule between risk and utilization benefits is derived by multi-objective evaluation of optimal operation rules for dynamic control of FOWL of cascade reservoirs. The research results of this project will provide important theoretical and technical support for formulating joint operation program for dynamic control of FOWL of cascade reservoirs.

针对梯级水库运行管理过程中防洪与发电、蓄水调度之间矛盾日益突出的问题，项目以长江中上游干支流控制性梯级水库为研究对象，通过识别梯级水库的防洪风险、欠发风险以及欠蓄风险，基于聚合-分解理论和预蓄预泄法，提出一种可实现有效预见期内防洪风险、欠发风险以及欠蓄风险最小，发电量和蓄水率期望值最大的梯级水库汛期运行水位联合动态控制方法，给出三维梯级水库汛期运行水位动态控制上限之间关联方程的解析解；耦合库容补偿法和预泄能力法，提出等库容置换法，挖掘汛期运行水位与防洪风险率、欠发风险率以及欠蓄风险率之间的关联规律，为风险分析提供风险约束，采用随机模拟法对梯级水库的防洪、发电和蓄水目标进行风险分析，通过对调度方案集的风险与兴利效益进行多目标决策，提取梯级水库汛期运行水位联合动态控制的优化调度规则，为梯级水库汛期运行水位联合动态控制方案的科学制定提供理论依据与技术支撑。

针对梯级水库洪水资源优化调控问题，本研究开展了梯级水库汛期运行水位多目标优化调度和梯级水库提前蓄水多目标优化调度等两个方面的研究。（1）溪洛渡-向家坝-三峡梯级水库汛期运行水位多目标优化调度研究结果表明：与单库优化调度指标相比，防洪风险最小方案在不降低原防洪标准的前提下，不仅能够降低0.007的发电脆弱度，还能增加0.64%水资源利用率和2.18%发电量（12.5亿kW·h/年）；而发电脆弱度最小方案在承担0.003防洪风险的前提下，能够显著提升水资源利用率和发电量，分别提高了5.43%和6.48%（37.1亿kW·h/年），发电脆弱度降低0.058。（2）梯级水库提前蓄水多目标优化调度研究结果表明：相较于单库常规调度，防洪风险最小方案，在不降低原防洪标准的前提下，提升了长江上游21座梯级水库年均发电量31.5亿kW·h、年均蓄满率1.13%和年均供水量5.21亿m3，发电脆弱度降低0.050；发电脆弱度最小方案，在小幅增加防洪风险（0.0016）前提下，可显著增加21座梯级水库年均发电量98.7亿kW·h、年均蓄满率1.92%和年均供水量8.81亿m3，发电脆弱度降低0.078。