本文以某扬黄工程梯级提水系统设计为模型，研究分析了在一级泵站取水系统已定，其余各级提水泵站级间泵站水泵和工作参数不同的情况下，以一级下游第一座泵站（二泵站）为例，对水泵特性曲线做定性相似分析，定量计算，根据首级泵站的提水灌溉流量需求，利用比例定律推算出水泵变频后的特性曲线，并对二泵站水泵工频和变频两种运行模式进行对比分析，确定二泵站水泵在各种灌溉提水流量下水泵运行工况点，合理确定水泵变频范围。该研究为大型梯级提水工程的水泵机组额定工况点的确定以及上下游泵站间的流量匹配提供了经验与参考。

Based on the model of water step-pumping system design of One pumping water engineering, it is analyzed that when the first pump station is already in operation, and the sets of pump units and the parameters are different in the following pumping stations, based on the first downstream pumping stations(pumping station Two),qualitative similarity analysis and calculation is done on pump performance curve, according to the water consumption of the first pumping station, various frequency pump performance curves are calculated based on the ratio formulas, various frequency and static frequency operating condition comparison analysis of is done on pumps in pump station Two, and pump real operating conditions and operating range are determined in various irrigation water flow. This research provides reference and guide for the determination of the rated operating conditions of the pump unit and the discharge matching in step pump stations project.