针对3台300 MW等级高背压循环水供热机组，试验研究了给水泵汽轮机实施一根转子的改造方案，在改造前、改造后高背压工况、改造后正常背压工况下的性能指标。青岛1号机组改造前300 MW工况下，给水泵汽轮机效率为78.185%；改造后正常背压工况下，三台机组给水泵汽轮机效率比设计值低6%~8%；高背压供热工况下，给水泵汽轮机的效率比设计值低15%~31%。本文对给水泵汽轮机的改造方案进行优化，分析计算了一新一旧的双转子方案和两根新转子方案。采用一新一旧的改造方案，即非供热期，给水泵汽轮机恢复原转子运行的经济性较好。采用电泵驱动的超临界350 MW高背压供热机组比上述采用一根转子的改造方案，厂用电率增加2.9%以上，供电煤耗率增加7.17 g/kW？h。
For three 300 MW grade high back pressure units heating with circulating water, the performance index of feed water pump turbine with one rotor reform scheme under three working conditions is studied experimentally. These conditions are operating condition before reform, high back pressure condition after reform and normal back pressure condition after modification. Under the condition of 300 MW before reform, the efficiency of feed water pump turbine of Tsingdao No.1 unit is 78.185%. Under normal back pressure condition after reform, the efficiency of three feed water pump steam turbines is 6%~8% lower than the design value. Under condition of high back pressure, the efficiency of three feed pump steam turbines is 15%~31% lower than the design value. The retrofit scheme of feed water pump steam turbine is optimized. The dual rotor scheme of a new and an old rotor as well as two new rotor schemes are analyzed and calculated. Adopting the dual rotor scheme of swapping a new and an old rotor, during non-heating period, the economy of the feed pump turbine to restore the original rotor is better. Compared with above modification scheme with one rotor, the auxiliary power consumption of a supercritical 350 MW high back pressure heating unit driven by electric pump increases over 2.9%, and its power supply coal consumption increasing 7.17 g/kW？h.
