梯级水电站水库蓄能利用最大化的长期优化调度

Long-term Optimization Scheduling Based on Maximal Storage Energy Exploitation of Cascaded Hydro-plant Reservoirs

以强迫弃水和有益弃水的混合弃水策略为基础,将梯级水电站看作一个整体,建立蕴涵末级水电站弃水电量最小、水力资源电站间分配时的发电量增益最大和水电站总发电量最大的梯级水电站水库蓄能利用最大化长期优化调度数学模型。构建了描述蓄水量、发电引用流量、弃水流量、水库前池水位和放水路水位之间关系的水电站水头特性详细数学模型。基于递归思想,建立以弃水流量和发电引用流量表示的水库蓄水量表达式。针对日调节水电站在长期优化调度中的特殊性,采用比例放大策略,建立了水库的等效库容约束条件。以一个三级水电站为例进行仿真分析,以混合弃水策略为基础的水库蓄能利用最大化优化调度数学模型可以提高约4%的综合发电量,表明了有益弃水策略在合理分配水力资源和提高电站综合发电效益方面的有效性。

A hybrid water spillage strategy for cascaded hydro-plants was proposed to realize the optimal distribution of water resource. By taking cascaded hydro-plants as a whole, a novel long-term optimization scheduling model named maximal storage energy exploitation model was established based on the rules of minimizing water spillage electric quantity for the last hydro-plant, maximizing electric quantity increments and total power output of cascaded hydro-plants. A detailed mathematical model for water head was constructed, which can describe relations among water volume, water discharge, water spillage, forebay elevation and tailrace elevation. By using recursion thought, a mathematical model for water volume was presented which is composed by water spillage and water discharge. A proportion strategy and equivalent storage capacity constraint condition were applied to describe the characteristics of daily regulating hydro-plant. To testify the effectiveness of the novel model, an example for three hydro-plants was executed. The simulation results prove that the model can realize the optimal distribution of water resource and enhance the synthesis electricity generation benefit of cascaded hydro-plant.