中文摘要：

变频给水泵组是一种常用的二次供水设备。对常用变频泵组多种组合情况的运行工况以及两处增压泵组的实际运行数据进行研究，发现在变频泵组中并联变频泵数量较多的组合，更能适应供水流量的变化，并提高泵组运行的效率，当变频泵达到3台及以上，节能效果较为显著，因此在工程选型中建议选用配置3台变频泵的3用1备泵组或3台变频泵与l台工频泵的4用l备泵组。

英文摘要：

Variable-frequency pump set is widely sued as secondary water supply equipment. By analyzing the running conditions of different combinations of the common variable-frequency pump sets and the practical operation data of two pressured pump sets, it was found that parallel operation of more pumps in variable-pump sets could adapt to the variances of water supply flow rate better and improve the pump set efficiency. When the variable-frequency pumps were more than three in a set, the energy-saving effect was obvious. Therefore, it was advised that there should be three variable-frequency pumps and one backup pump in the practical engineering project or three variable-frequency pump, one power-frequency pump and one backup DumP.