基于来水不确定性的梯级水电站负荷调整耦合模型——以锦官电源组梯级水电站为例

针对来水不确定性引起的实际调度要求与原定发电计划的偏差问题,一方面结合风险管理内涵和梯级水电站发电调度操作规程,建立了梯级水电站安全运行预警机制,对发电计划进行滚动监测与评估;另一方面,基于误差分析技术和水库调度理论,建立了梯级水电站负荷调整耦合模型,并以预警结果为时间控制节点,构建二者的嵌套应用模式,同时提出了一种计及电网安全约束的负荷调整逐层递进求解算法。以雅砻江流域锦官电源组梯级水电站为实例进行计算,结果表明,所建模型可有效解决来水不确定性(偏小或偏大)导致的电站被迫降低出力运行或水库弃水问题,制定的负荷调整方案满足电网安全稳定运行约束和水电站水库运行要求,验证了所建模型的合理性。

A coupling model of load adjustment for cascade hydropower stations based on inflow uncertainty: A case study of Jinping-guandi cascade hydropower stations

To solve the deviation caused by inflow uncertainty between the actual operation requirements of cascade hydropower stations and its original power generation schedule, on the one hand, an early warning mechanism for safe operation, which combines risk management connotation and hydropower stations operation rules, is proposed to meet the goal of establishing continuous monitoring and evaluation on the schedule. On the other hand,a new coupling model of load adjustment for cascade hydropower stations is developed based on error analysis method and reservoir operation theory. By setting the early warning results as time control nodes,a nested application mode for the mechanism and the model is constructed. Meanwhile, an algorithm considering security constraints in the power grid is introduced herein. Consider Jinping-guandi cascade hydropower stations as an example. The modeling results show that the proposed model can effectively solve the problem that the power plant is forced to reduce output or release surplus water due to inflow uncertainty. The developed load adjustment scheme can also meet the requirements of hydropower stations operation and ensure safety and stability of power grids. Hence, the rationality of the model is verified by the modeling results.