亚临界600MW机组通流改造引发汽流激振问题处理

针对火电机组日益严峻的节能减排形式,国内许多600MW等级亚临界机组进行了相应的升级改造。然而,由于对汽封间隙进行调整等节能措施的应用使得汽轮机内部流场发生改变,在机组改造后出现轴振突增的汽流激振现象。因此,机组不得不投运单阀方式,低负荷运行经济性严重下降。针对上述问题,本文提出了一种综合优化策略,根据不同工况设计了两种顺序阀优化方案,有效缓解了机组安全性和经济性的矛盾。本文对大功率汽轮机通流改造后的运行优化具有一定的指导意义。

In view of the increasingly severe energy saving form for power units,many domestic 600MW subcritical units have been upgraded accordingly.However,with the application of energy saving measures such as adjusting the gland clearance,the inner flow field of the steam turbine has been changed.After the modif ication of the steam turbine,the steam flow excitation phenomenon exists,such as shaft vibration increased abruptly.Therefore,the unit had to operate in a single valve mode,its economiceff iciency will be reduced in this low-load status.To solve these problems,a comprehensive optimization strategy is proposed in this paper.Two sequential valve optimization schemes are designed for different working conditions,which effectively alleviate the contradiction between safety and economy of the unit.This paper has a certain guiding significance for the operation optimization of large unit it's after flowing through transformation.