融 合 多 模 态 转 子 振 动 特 性 的 电 机 轴 承 故 障定 位 与 诊 断 方 法

To ensure the reliability and safety of motor operation，vibration analysis is widely applied in the condition monitoring and fault diagnosis of its rolling bearing components. However，traditional monitoring methods are insensitive to weak faults and cannot locate faulty bearings through the vibration signals collected by a single sensor. In this research，the dynamical model of the flexible rotor-bearing system was established using the finite element method to obtain the nonlinear dynamical responses and its variation law of the rotor system with different types and positions of faulty bearings. A diagnostic method for fault location of rolling bearings based on multimodal rotor vibration characteristics and on-rotor sensing (ORS) technology is proposed. Both simulation and experimental results show that the coupling vibration between the pulse excitation of faulty bearing and the rotor system modes enhance the amplitude of the fault feature components near the natural modal frequency. The vibration response energy of the 4th order mode of rotor system near 1500 Hz is an important feature for identifying the position of the faulty bearing. The proposed method achieves the comprehensive diagnosis of bearing fault types and faulty bearings localization using a signal ORS single sensor node and has significant advantages over traditional diagnostic methods.