汽轮机阀门流量特性函数优化和对机组安全性经济性的影响

Optimization for the flow characteristic function of turbine valves and the influences on safe and economic operation

对某300MW亚临界机组的汽轮机阀门流量特性进行了优化试验,对原特性函数引起的负荷突变、协调品质差、AGC不能投入、煤耗高等问题进行了分析,对顺序阀和单阀方式下的阀门流量特性函数进行了优化,包括对流量变化过陡和过缓区段的调整、顺序阀方式下的阀门重叠度的重新选择等。优化后该机组运行稳定,AGC方式下变负荷及一次调频能力增强,且阀门节流损失更小,在低负荷下煤耗约降低2g/(kW·h),机组运行的安全性和经济性大大提高。

The optimization test was performed on the valve flow characteristics for 300 MW supereritical power unit. Based on this, several problems were analyzed, including load mutation, poor coordination quality, AGC failure and high coal consumption resulted from original characteristic function. The flow characteristic function of valves was optimized under sequence-valve and single-valve modes, including adjusting the too steep or too slow sections of flow variation, re-selecting the overlap of valves under sequence-valve mode, etc. After the optimization, the power unit went into stable operation, the load variation and primary frequency regulation capability has been enhanced; the throttling loss of valves has been reduced, the coal consumption decreased by 2 g/（kW, h） under low load, the stability and security of unit have been increased greatly.