对华能海门电厂2台1 036 MW机组冷端系统在循环水泵双速改造前后进行了运行优化试验，根据试验数据拟合出汽轮机背压和功率微增曲线及汽轮机功率修正计算公式，并计算出了凝汽器变工况特性；采用综合煤价和电价比较法得出循环水泵双速改造前后的推荐运行方式。实践证明循环水泵双速改造后能达到进一步节能的目的，使电厂获得了最大的经济效益。

The operation optimization tests of cold end system are conducted by double speed operation innovation of water circulation pump in two 1 036 MW steam turbine units of Huaneng Haimen power plant. According to the test data, the slight increasing curves of exhaust steam pressure and power are fitted, the correction formula of power is obtained, and the characteristics at variable operating conditions of condenser are calculated. Combined with the integrated coal and electrovalence comparison method, the operation mode for water circulation pump by double speed operation innovation is recommended. It is proved that the double speed operation of water circulation pump can reach the goal of energy saving and obtain the maximum economic benefits for the power plant.