磁拉力及油膜力作用下水轮机转子系统分析

摘要

In order to further study the nonlinear dynamic behavior of hydroelectric generating set rotor system,the nonlinear dynamics of a hydroe-lectric generating set was mainly researched after considering the effects of the unbalanced magnetic pull and oil film forces. The hydroelectric gen-erating set rotor system nonlinear dynamic model and differential equation were established. The nonlinear dynamic response of a hydroelectric gen-erating set was analyzed through numerical analysis methods. The results show that the increase of excitation current can significantly increase the vibration amplitude of rotor. With the excitation current increases,rotor systems exists periodic motion and quasi-period motion. Moreover,system response presents a complex nonlinear change law with the system rotation speed change.%在机组存在转轴平行不对中和发电机转子质量偏心的基础上，同时考虑机组转子系统受到不平衡电磁拉力和油膜力的作用，研究在这两种力共同作用下转子系统非线性动力学问题。建立了水轮发电机组转子系统非线性动力学模型和微分方程，运用数值分析方法，系统地分析了转子系统非线性动力学响应。结果表明：励磁电流对系统的响应有明显影响，随着励磁电流增大，转子系统存在倍周期运动和复杂的拟周期运动；机组转速的变化使系统响应呈现复杂的非线性变化。