联合循环机组汽机启动过程中的热应力控制

联合循环机组相对于火电机组而言,启停次数频繁。尽管采用不正确的方法也能顺利地启动、停机,但不兼顾机组自身热应力变化而随意操作,会对机组寿命造成很大的影响。论述了汽机启动过程中如何通过区分不同外部条件来设置机组转速、负荷,同时协调燃机排气温度控制,以达到减少汽机主要部件热应力,提高运行寿命的目的。

Thermal stress control during starting process of combined cycle unit steam turbine

The difference between the combined cycle unit and the coal-fire unit is that the former undergoes frequent starting and loading cycles. In many instances, a turbine may appear to start without difficulty, in spite of the use of improper methods. But close inspection may later reveal unnecessary damage. Some units were used as example to explain the steam turbine control strategy for the thermal stress control during startup, and the coordinate control for the exhaust temperature in gas turbine is introduced. These strategies are used to reduce the thermal stress in main part of the steam turbine and thus to extend the life of steam turbine.