【摘要】 针对现有迭代希尔伯特变换(IHT)存在端点效应及滤波器设计主要依靠先验知识问题,提出改进的IHT方法并用于机械故障诊断。分析IHT方法中端点效应原因,提出用基于对称延拓信号方法消除端点效应影响及用自适应的零相位滤波器取代原方法中的固定滤波器。将改进的IHT方法与原方法进行仿真对比分析表明,该方法的解调精度更高,并能有效抑制端点效应。利用改进的IHT方法进行轴承故障诊断试验表明,该方法解调效果更好,能更准确提取外圈故障特征。更多还原

【Abstract】 As an end effect exists in an iterative Hilbert transformation(IHT) and design of filters depends on a priori knowledge,an improved approach for mechanical fault diagnosis was proposed.Analyzing the causes of end effect in IHT,a method based on symmetric extension of a signal to eliminate the end effect was proposed.Meanwhile,an adaptive zero-phase filter was adopted to replace the fixed one in the original method.Simulations showed that the proposed method has a higher accuracy of demodulation and can effectively inhibit the end effect,compared with the original method.At last,the method was used to analyze faults of rolling bearings and the results showed that the proposed method has a better effect of demodulation and can extract the faults features of out races more accurately.更多还原