基于模式匹配的振动信号整周期采样方法

Mode Matching-Based Vibration Signal Full Period Sampling Method in Rotation Machinery

把模式匹配技术引入了旋转机械振动信号整周期采样领域。该方法的过程为:先通过傅里叶变换获得大致的基频振动周期,然后根据振动周期提取匹配用波形,再沿着振动数据滑动求匹配波形与振动数据段的相似性来查找周期起止点,相似度大于设定的阈值的数据段存在周期起止点,用三次样条在周期起止点间进行插值,就获得了整周期采样的数据。对该方法进行了仿真和试验研究,结果表明:该方法能准确地对振动信号进行整周期采样,抗干扰性能良好,可以广泛地用于旋转机械振动信号整周期采样领域。

The mode matching-based technology is introduced to the field of vibration signal full period sampling in rotation machinery.The steps of the method are as follows.Firstly,get the approximate fundamental period of the signal by Fourier transformation,and then truncate a segment from the signal in the light of the approximate period for matching.Secondly,calculate the correlation coefficient between truncated segment and original vibration data to find out a data segment containing the begining and the end points of a period of the signal.If the correlation coefficients in a data segment are greater than preset threshold value,there should be the begining and the end points in the segment.Finally,generate required full period data by interpolation between the begining and the end points of the segment with the aid of a cube spling function.Simulation and testing results show that the method can accurately sample the data in a full period and its anti-interference capability is quite good.The method can be widely used in the field of rotation machinery for full period sampling.