永磁电动机转子非线性动力特性

NONLINEAR DYNAMIC CHARACTERISTICS OF PERMANENT MAGNET MOTOR ROTOR

以转子动力学和非线性动力学为基础 ,建立永磁电动机转子系统的非线性模型 ,用数值方法得到系统在特殊参数域中的分叉图、相图、轴心轨迹、Poincar啨截面图、功率谱以及幅值谱?治霰砻?,磁拉力刚度是影响永磁电动机转子系统动力学特性的重要因素之一 ,由于轴承非线性引起的永磁电动机转子响应随着磁拉力刚度的增加而增加 ,为此在设计永磁电动机的过程中应尽量减小磁拉力。偏心、电机转速的变化均会使电机转子产生混沌运动而导致转子失稳 ,电机转速的微小变化可能使转子响应产生辐值跳跃现象 。

Based on rotor dynamics and nonlinear dynamics theory, the nonlinear model of magnet motor rotor system was established. With numerical analysis methods, the bifurcation diagrams, phase portrait, the shaft centerline orbit, the Poincaré mapping diagram, the power and amplitude spectrum are acquired in some typical parameters of the system. The result of calculations shows magnetic pull stiffness is one of the key factor influencing the dynamic characteristics of magnet motor rotor system, permanent magnet motor rotor response resulted in by nonlinear of bear increases with increase of magnetic pull stiffness, therefore in the course of design of permanent magnet motor some measures must be taken to decrease magnetic pull. The changing of the rotational speed and eccentric distance can induce chaotic motions of permanent magnet motor rotor and it can cause loss of the stability of rotor, the small changing of the rotational speed can result in amplitude jump phenomenon and induce violent vibration, further more, it can cause failure event of rotor shaft.