凝汽器低真空保护动作原因分析

Cause Analysis of Condenser Low Vacuum Protection Action

汽轮机凝汽器的真空度对于机组的运行安全和经济性具有很大影响,在机组运行过程中,凝汽器运行状态的恶化将会直接导致汽轮机热耗、汽耗增大和出力的降低;此外,真空降低会引起汽轮机的排汽缸温度升高以及汽机轴承的中心偏移,进一步还会引起汽轮机组的振动。某电厂2020年4月30日#2机启动过程中凝汽器真空变送器显示数据正常,却发生凝汽器真空低开关保护动作机组跳闸的事件,通过分析变送器数据、测点位置、压力开关动作值等各方面因素,找到本次跳闸事件的原因,提出解决办法。

The vacuum degree of the steam turbine condenser has a great influence on the safety and economy of the unit operation.During the operation of the unit,the deterioration of the operating state of the condenser will directly lead to the increase of the heat consumption and steam consumption of the steam turbine and the reduction of the output;in addition,the decrease of the vacuum will cause the temperature of the exhaust cylinder of the steam turbine and the center deviation of the turbine bearing,and further cause the steam Vibration of wheel set.On April 30,2020,during the start-up of No.2 unit in a power plant,the data displayed by the vacuum transmitter of the condenser was normal,but the protection action of the low vacuum switch of the condenser occurred.By analyzing the data of the transmitter,the position of the measuring point,the action value of the pressure switch and other factors,the causes of the trip event were found out,and the solutions were put forward.