基于同步提取变换与阶比分析的轴承变转速故障诊断

Fault Diagnosis of Bearing in Variable Speed Based on Synchronous Extraction Transformation and Order Analysis

针对基于瞬时频率估计的阶比分析方法中,瞬时频率难以估计的问题,提出一种基于同步提取变换(SET)的阶比分析方法,对轴承的变转速振动信号进行分析。该方法利用SET良好的能量集中特性,提取强噪声环境下轴承振动信号中的瞬时频率,通过对计算瞬时频率的鉴相时标,对时域信号进行等角度采样,从而得到稳态的角域信号。通过分析轴承实验台的变转速振动信号表明,该方法能够有效抑制噪声的干扰,精确地提取出变转速信号的瞬时频率,成功地实现变转速状态下轴承的故障诊断。

In order to solve the problem that the instantaneous frequency is difficult to estimate in the order analysis method based on the instantaneous frequency estimation,a order analysis method based on the synchronous extraction transform(SET)is proposed to analyze the variable speed vibration signal of the bearing.In this method,the instantaneous frequency of bearing vibration signal in strong noise environment is extracted by using the good energy concentration characteristic of set.The time domain signal is sampled equiangular by phase discrimination time scale of calculating instantaneous frequency,so as to obtain the steady angular domain signal.By analyzing the variable speed vibration signal of the bearing experimental platform,it shows that this method can effectively suppress the noise interference,accurately extract the instantaneous frequency of the variable speed signal,and successfully realize the fault diagnosis of the bearing in the variable speed state.