水轮发电机组轴系横向振动的大扰动暂态模型

LARGE DISTURBANCE TRANSIENT MODEL FOR SHAFTING LATERAL VIBRATION OF HYDRO TURBINE GENERATING SETS

水轮发电机组大扰动暂态过程中角速度急剧变化,其振动激励的主导因素是轴系作用力矩,即水轮机力矩和发电机电磁力矩的变化.本文以水轮发电机转子和水轮机转轮为核心,分析其能量构成,建立适用于机组暂态分析的轴系横向振动微分方程模型.通过定义广义动量,将轴系振动模型化为非线性一阶微分方程形式,进而与机组运动方程相结合构成轴系大扰动分析的一阶微分方程组模型,该模型中机组轴系的各种附加作用力作为轴系的输入激励,增加了轴系振动模型的通用性.最后,结合实例进行了仿真分析.

The angular speed of hydro turbine generating sets(HTGS)changes rapidly in large disturbance transient,in which the dominant factors of vibration excitation are changes of shafting torque,hydro turbine torque and generator electromagnetic torque.Taking generator rotor and hydro turbine runner as the core,this paper establishes shafting lateral vibration differential equation of HTGS,which can be applied to transient analysis.Shafting model is transformed into first order differential equation groups,and is combined with motion equation of HTGS to build integrated model,which can be used to large disturbance transient.Various additional forces of shafting are taken as input excitation in proposed model,which the generality of model is good.At last,an actual example is simulated.