考虑余留效益的水库长期优化调度图集及应用

Long-term optimal operation atlas of reservoirs considering remaining benefits and its application

优化调度图是水库优化调度的重要工具,余留效益是制约水库中长期优化调度效果的关键因素。本文基于水库坝址历史流量信息,计算水库年末蓄水的长期余留效益;然后根据各时段的来水流量量级及频率,应用动态规划方法,从年末逐时段逆序计算各时段初不同水位的最优期望效益;再建立各时段在时段初水库所处不同水位时,多种典型来水情况下的最优决策图,构成水库长期发电优化调度图集。老挝南欧江七级水电站实例研究结果表明,利用本方法开展水库长期优化调度,原理清晰,操作简单,效益比常规调度和调度函数分别提高了1.03%和0.87%。本方法充分利用水库历史径流信息和预报流量信息,考虑了水库决策对余留效益的影响,为水库长期优化调度决策提供了新的途径。

The optimal operation chart of a hydropower station is a useful tool to guide its optimal operation, and the remaining benefit is a key factor restricting the effect of an operation scheme. Based on the information of historical flows at the dam site, this paper calculates the long-term remaining benefit for the reservoir storage at year end. And, from the magnitude and frequency of the inflows in each period,we calculate optimal expected benefits for different reservoir water stages at the beginning of each period in a reverse order starting from year end, using the dynamic programming method. Then, optimal decision charts are made for different typical inflow conditions in each period based on the different reservoir stages at its beginning, so that the charts of all the periods can serve as an optimal operation atlas for longterm power generation of the reservoir. A case study of the Nam Ou VII hydropower station in Laos shows this new method offers long-term operation schemes that are simple and on clear principles, achieving a benefit of 1.03% higher than traditional operation and 0.87% higher than function-based operation. This demonstrates that for long-term optimal operation of reservoirs, it is of great significance to make use of historical runoffs and flow predictions and to consider the impact of reservoir decision on remaining benefits.