响应调峰需求的中小型流域梯级电站短期调度方法

当前我国许多中小型流域水电站水库调节性能较差、上下游水力联系紧密，部分机组开停机仍然依靠人工调整，如何快速制定合理的短期调度方案成为这类水电站群面临的实际难题。针对上述问题，提出响应调峰需求的中小型流域梯级电站短期调度方法。首先采用分段法将典型日负荷曲线重构为与实际负荷趋势相似但更为平整的新负荷曲线；其次以期末水位为控制目标，采用改进逐次切负荷法生成平稳且满足约束条件的初始出力过程；然后采用分段弃水修正策略，变步长增减弃水区段出力直至弃水处理完毕；最后以剩余负荷最大值最小为目标，依电站上下游顺序循环执行改进逐次切负荷法和弃水修正策略直至目标函数值变化满足精度要求。在福建金溪流域梯级水电站群的实例应用表明，本方法能够获得比目前结果更平稳的调度方案，在保证时效性的前提下可有效增加梯级发电量，响应电网调峰需求的同时实现水资源高效利用。

Short-term scheduling methods for peak load responding demand of cascade hydropower stations in small and medium-sized river basins

At present, due to the characteristics of poor regulation capacity, close hydraulic connections between upstream and downstream hydropower stations, and depending on manual adjustment to start or shut down units, how to formulate a reasonable short-term scheduling scheme quickly becomes the practical problem faced by such kind of hydropower station groups.Based on the above problems, this paper proposes a short-term scheduling method considering peak shaving demand for small and medium-sized hydropower stations.Firstly, a typical daily load curve is redrawn into a new load curve which is similar to the initial curve but steadier by subsection method.Secondly, taking the water level of the reservoir at the end of 24 hours as the control target, the improved successive load shedding method is adopted to generate a stationary initial output process satisfying the constraints.Thirdly, adopting the modified strategy of spilling water in subsection, the output in the sections of spilling water will be increased or decreased with varying step length until the modification of spilling water is completed.Finally, with the objective of minimizing the maximum residual load, the improved successive load shedding method and the modification strategy of spilling water are implemented repeatedly from upstream power stations to downstream ones until the error of the objective value meets the accuracy requirements.The method is applied to solve the short-term scheduling problem involving the cascaded plants located in Jinxi Basin of Fujian province, China.The results indicate that the proposed method can obtain a more stable operation scheme than actual results, effectively increase the cascade power generation under the premise of ensuring timeliness, respond to the peak shaving demand of the power grid and achieve efficient utilization of water resources.