齿轮箱复合故障诊断的信号共振分量能量算子解调方法

Energy operator demodulating of signal's resonance components for the compound fault diagnosis of gearbox

当齿轮箱中的齿轮和轴承同时出现故障时,较弱故障特征往往会淹没在较强故障特征中,直接对振动信号做解调分析诊断故障通常会出现漏判或误判。针对这一问题,提出了信号共振分量的能量算子解调方法,并将其应用于齿轮箱复合故障诊断中。该方法采用信号共振稀疏分解方法对同时含有齿轮和轴承故障的齿轮箱振动信号进行分解,将表征齿轮故障特征的高共振分量(幅值调制成分)和表征轴承故障特征的低共振分量(冲击脉冲成分)互相分离;然后分别进行能量算子解调分析,计算瞬时幅值;最后通过瞬时幅值谱分析分别诊断齿轮和轴承故障,进而实现齿轮箱复合故障的诊断。仿真算例和应用实例说明了该方法的有效性。

When the gear′s fault and the bearing′s fault in a gearbox occur at the same time,the symptoms of the weak fault usually is submerged in the strong fault symptoms.Therefore,it is difficult to detect the weak fault directly through the demodulating analysis of the gearbox vibration signals.For that problem,a method of compound fault diagnosis of gearbox is proposed based on the energy operator demodulating of signal′s resonance components.In this method,the gearbox vibration signal is decomposed using resonance-based sparse signal decomposition.The higher-resonance component（the amplitude modulation component）indicates the gear′s fault and the lower-resonance component（the impulse component）indicates the bearing′s fault to separate them from each other.The separated amplitude modulation component and the impulse component are then analyzed by energy operator demodulating,and each of their instantaneous amplitude can be calculated.According to the spectrum of the instantaneous amplitude,the gear′s fault and the bearing′s fault can be diagnosed respectively,so the compound fault of a gearbox can be diagnosed.Some simulation and illustrative examples proved the effectiveness of the method.