汽轮机ADM值梯度变化影响分析

Influence Analysis of ADM Value Gradient Change of Steam Turbine

长兴某电厂配置机组为调峰天然气机组,启停较为频繁,汽包水位的控制是机组停运过程中面临的最大跳机风险点。该电厂机组拥有3个不同压力等级的汽包,100%容量的旁路。机组停运过程中,ADM值控制着汽机调门切至旁路的动作速率,引起系统压力变化,从而影响汽包水位。ADM值越大则切换速率越快,水位波动越大,但ADM值过小会拉长切换过程,影响经济效益。

The unit of a power plant in Changxing is confi gured as peak shaving natural gas unit,which starts and stops frequently.The control of steam drum water level is the biggest risk point of unit trip in the process of unit shutdown.The power plant unit has three steam drums with different pressure levels and bypass with 100%capacity.During the shutdown of the unit,ADM value controls the action rate of switching the steam turbine regulating valve to the bypass,causing the change of system pressure and aff ecting the drum water level.The larger the ADM value,the faster the switching rate and the greater the water level fluctuation.However,too small ADM value will lengthen the switching process and affect the economic benefi ts.