固定式刚性联轴器不对中弯扭耦合振动特性

以水轮发电机组固定式刚性联轴器平行不对中故障为研究对象,从动力学角度推导不对中机理,建立平行不对中弯扭耦合振动微分方程.基于该微分方程,理论上分析了弯振、扭振之间的相互影响;从转速、质量偏心、不对中量和阻尼系数等几方面进行弯扭耦合振动数值仿真.仿真计算表明:弯振与扭振通过固结于转子的偏心质量相互耦合;弯振主要包含工频成分,不对中越严重,工频所占比例越大.扭振包括极大的直流分量和少量倍频成分,过大的直流分量对机组安全不利.

Coupled lateral and torsional vibration properties of parallel misaligned fixed rigid couplings

The object of this research aimed at the parallel misalignment fault of fixed rigid coupling(FRC).From the theory of energy,the differential equations of coupled lateral and torsional vibrations for the parallel misalignment fault of FRC were formed.The mutual influence of lateral vibration and torsional vibration was analyzed qualitatively based on the set of equations.Sequentially,a numerical simulation of the coupled lateral and torsional vibrations of FRC is carried out by considering several aspects,such as changed speeds,mass eccentricities,misalignment values and damping coefficients.It is shown that lateral vibration and torsional vibration are coupled by the unbalanced masses fixed on the rotor.The frequencies of lateral vibration mainly contain one time frequency component.More serious the misalignment is,bigger the scale of one time frequency component is.The frequencies of the torsional vibration contain DC component and a few higher times frequency component.Too bigger DC component would do harm to the generation set.