平行不对中转子系统的电机电流特性

摘要

为通过监测电机电流信号以实现对转子系统故障的识别与诊断,考虑圆盘不平衡因素,建立平行不对中转子系统动力学模型,然后应用拉格朗日方程,推导出转子系统运动微分方程,并以电机的电磁扭矩为纽带,在MATLAB/Simulink环境下建立三相异步电动机—转子系统机电耦合模型,最后应用傅里叶变换对电流信号进行频谱分析,研究平行不对中故障激励下电机电流信号的耦合特性.仿真结果表明:不平行故障会使电流信号激发出的边频分量,随着不平衡量的增大,还会激发出的边频分量;考虑质量偏心,电流信号还会激发出的边频分量,但当时,的边频分量会被淹没,反之,该边频分量则比较明显.%In order to achieve rotor system's fault identification and diagnosis by monitoring the motor current signal, the dynamic model of rotor system is developed after considering the parallel misalignment of rotors and unbalance of disk.Then the motion equations are derived on Lagrange's approach and the electromechanical coupling model consisting of three-phase asynchronous motor and rotor system is built based on the electromagnetic torque of the motor.The model is analyzed in the MATLAB/Simulink and meanwhile the motor current signal is processed by Fourier transform at last. Study on the coupling characteristics of Parallel-Misaligned fault excitation and motor current signal will be completed.Simulation results show that the side-frequency of will be excited and the side-frequency of also will be excited with the increase of misalignment values;and the side-frequency of will be excited after considering the unbalance of disk,but it will be drowned if.