基于信号共振稀疏分解与重分配小波尺度谱的转子碰摩故障诊断方法

提出了基于信号共振稀疏分解与重分配小波尺度谱的转子碰摩故障诊断方法。与常规的基于频带划分的信号分解方法不同，信号共振稀疏分解方法根据信号中各成分品质因子的不同，将信号分解成高共振分量和低共振分量。当转子出现碰摩故障时，振动信号往往由以转频及谐波为主要成分的周期信号、包含转子故障信息的瞬态冲击信号以及噪声组成。周期信号为窄带信号，具有高的品质因子，可分解为高共振分量；而瞬态冲击信号为宽带信号，具有低的品质因子，可分解为低共振分量。本文方法先利用信号共振稀疏分解方法从转子碰摩信号中提取冲击成分，再对提取的冲击成分进行重分配小波尺度谱分析，最后根据尺度图中冲击成分的周期诊断转子碰摩故障。算法仿真和应用实例验证了该方法诊断转子碰摩故障的有效性。

Rub-impact Diagnosis of Rotors by Using Resonance-based Sparse Signal Decomposition and Reassigned Wavelet Scalogram

A method for rub-impact diagnosis of rotors based on resonance-based sparse signal decomposition and reassigned wavelet scalogram was proposed in this paper. Differ form the tradition signal decomposition method based on frequency band，resonance-based sparse signal decomposition method decomposed a signal into high resonance component and low resonance component according to the Q-factor. When the rub-impact occurred in a rotor system，the vibration signal was composed of periodic signal mainly consisted of rotor frequency component and its harmonics，transient impulse signal with rotor fault information and noise. Periodic signal belongs to narrow band signal and had a high Q-factor，and could be decomposed into high resonance component；while transient impulse signal belongs to wideband signal and had a low Q-factor，and could be decomposed into low resonance component. In the proposed method，impulses，which were drawn from rub-impact signal of a rotor by using resonance-based sparse signal decomposition，were analyzed by reassigned wavelet scalogram and the fault diagnosis of rub-impact in a rotor system was carried out according to the impulse period in the scalogram. Simulation and application example show that the proposed method was effective in diagnosing rub-impact fault of rotor systems.