吸振器与球平衡器并用控制转子不平衡振动的理论研究

Theoretical study on imbalance vibration of rotor controlled by dynamic vibration absorber and automatic ball balancer simultaneously

球式自动平衡器(Automatic Ball Balancer,简称ABB)可以在临界转速以上区域完全消除转子未知不平衡量,但其缺点是在临界转速附近会引起大振幅的共振响应和不稳定振荡。为此增加动力吸振器(Dynamic Vibration Absorber,简称DVA)来克服其缺点,改善其抑振性能。以Jeffcott偏心转子模型为研究对象,根据拉格朗日方程建立了吸振器、球平衡器单独使用以及两者结合使用时控制转子不平衡振动的动力学方程,使用谐波平衡法理论求解新耦合系统的振幅表达式,并分析各参数对稳态幅频曲线的影响规律以获得较合适的参数,采用龙格-库塔数值方法计算得到稳态幅频特性图和瞬态振幅时域变化曲线。对比结果表明,两种手段并用的新方案有效降低了转子经过临界共振区时的振动水平,并使转子在临界转速以上区域衰减为零振幅,达到了融合两者优点的目的,具有更优良的抑振效果。

An Automatic Ball Balancer(ABB)can entirely eliminate the unknown imbalance of the rotor above the critical speed.However,it has the disadvantage of causing large amplitude resonance response and unstable oscillation near the critical speed.To overcome these shortcomings and improve its vibration suppression performance,this paper proposes the addition of a Dynamic Vi-bration Absorber(DVA).Using the Jeffcott eccentric rotor model as the research object,dynamic equations are established to con-trol the unbalanced vibration of the rotor when the DVA and ABB are used either separately or in combination,based on the La-grange equation.The harmonic balance method is used to solve the amplitude expression of the new coupling system,and the influ-ence laws of each parameter on the steady-state amplitude-frequency curve are analyzed to obtain more suitable parameters.The steady-state amplitude-frequency characteristic diagram and the transient amplitude time-domain change curves are obtained using the Runge-Kutta numerical calculation method.The comparison results show that the new scheme of combining the two methods effectively reduces the vibration level of the rotor when passing through the critical resonance region,and causes the rotor to attenu-ate to zero amplitude above the critical speed.This new scheme achieves the goal of combining the advantages of the two methods and provides superior vibration suppression.